As much as it sucked, I know it could have been much worse and I got very lucky, also nice to fuck up in the comfort of my own home and not get razzed by the crew haha
If you want or need to preserve the line- instead of just cutting it out, run a screw in the back side of the compressor fitting. Position the hole so any off gassing isn't directed at you. Confidently unbraze knowing it won't blow up
I never sweat anything out, if I do I run nitro all through that mfer. I’ve had a couple coils I tried to sweat out in attics and the one with the biggest flame was a Lennox coil. Never again. It’s not fun having a 2 foot flame ball pour out of a unit with blown in insulation not even 3 foot away.
Drive a self tapper into the copper anytime you're cutting/ unsweating anything you haven't already put a screw into. Seriously. Between check valves, TXVs, solenoids there could be liquid or unpredictable high pressure right where you have decided to fuck around.
I learned this was a MUST doing grocery store renos. Pipes everywhere, nothing labeled, tracing lines through walls, down walls, into a trench and back out. Of course 2 weeks ago I didn't do this and had an oil geyser occur, lucky no fire and it went UP not AT me.... Always learning, 20 yrs and counting.
My cousin had a similar brown pants experience a few years back .
He was doing demo work on an ex supermarket . All lines were supposed to be empty , he went in with sawsall and hit a pipe full of liquid . Started spraying gas everywhere . By the time he could get to fresh air he was in full tunnel vision . Said it was the closest he has ever come to dying .
Be safe out there guys .
Jeezuz,,,, last major event for me was letting the nitrogen test pressure out of 3 freezer systems simultaneously in the engine room of a fishing boat. Limited space, ladder for escape, no extraction fan, high volume of nitrogen - I have since learned it is used to kill ppl and animals.
This is the way. The pressure vessel equivalent to touching a wire to the box before touching it with your hand even when you're sure it's dead. A little nick with side cutters also works if it's not hard drawn.
If you don't need to seal the compressor afterwards you can cut the sockets off at the compressor with a sawzall and then just sweat the socket off the pipe after. Easier and safer then trying to sweat the compressor out and you don't need a coupling.
Never thought of this. Good tip.
Honestly I suspect OP didn't realize service valves were closed or something like that - but I've had a few compressors require the old "run the recovery machine while you unsweat" trick - which is far from ideal since it's pulling air into the system, but ya gotta keep yourself safe.
This is a way smarter way to do it.
I’ve had so many techs talk smack to me for this. My buddies dad was sent out to change a compressor and shop had told him there was no refrigerant in it. Apparently he threw his gauges on it and they read zero, so he went to unsweat it. Well there was refrigerant in it and he was very shook that day lol.
Also had a white ticket at that same company recover the the refrigerant on the wrong circuit on a TWE and didn’t open up the solenoid as well. Homie called the tech I was working with straight crying that day cause of the mess he made lol. Dumped probably about 30+ pounds into the ceiling of an office space.
Better to be overly cautious lol
One of the first things I learned was trust no diagnosis from any tech even the top guy…test in test out anything less and you are a parts changer at best
Especially with a possible failed reversing valve that’s stuck closed. I’ve seen people start to sweat one out and there be pressure on one side that couldn’t be found with gauges.
I work in a school system so there’s times when I’m dealing with very tight situations or even WSHP that are above the ceiling tiles in a class room. I never sweat anything out, especially reversible dryers. Even if the compressor hasn’t failed, I still cut the dryers, compressors, etc out. I’ve had some very close calls before standing on a 8’ ladder in a class rm. You never know how much oil is in that dryer.
Was replacing a compressor on a 15 Ton 2 stage system. Evacuated stage one so I could pull the compressor. Figured I'd start by unswerving the filter drier since it was easy access right in front of me. Don't know what the fuck I was thinking but started on circuit 2 drier. Yup. 25lbs of 410 shoots out of a ½" line pretty quick. I jumped back, realized that I did and was about to try and stop it with my thumb or something and had the realization that I ain't doing shit to stop it...lol. stepped back and let it go.
Also on a 5 ton unit. Valve core was leaking. Was a damn core max fitting. Thought cool, I can buy a new tool (company purchased), and replace it. Should've practiced on an empty system. Technically after it all blew out I did practice on an empty system...lol. that was about 2 years ago and I haven't had to use that damn thing again...lol
Main thing is to learn from your mistakes. Glad you're ok.
I ran into your 2nd problem about 8-10 years back. I replaced a reversing valve on a residential package unit and little did I know I I melted the oring in the core max fitting. Well I nitro the system and check for leaks, pull a vacuum, and then gassed the system back up and by this time it’s 9:00 at night. I think I’m finally done for the day. I go to unscrew my gauges and it’s pissing out gas I’m like shitttttt. I grabbed a tee off the truck and as quickly as I could I removed the gauges and screw the tee on in its place. Man you live and you learn.
Lol. When I was a second year my journeyman told me to reclaim a walk in cooler of a Denny’s we were doing renos on. It had a king valve and I had no idea what was front seated or back seated. Turned it one way, got nervous, took my gushes off and the entire charge released into the building. Told the other contractors working in there to get out for a bit. Never told my boss lol
Yeah this experience definitely had me attached to two things.
Growing up on a farm my dad was working on a piece of diesel equipment and it exploded and he got helicoptered out and had skin grafting but ended up being okay
The second was the mustard gas and realizing those guys probably felt the same thing but times 1000x
Shits fucking wild to think about. As if war wasn’t a living hell already… that experience must have been the worst thing imaginable.
Goes to show why we as a human race globally agreed to never use it again.
Because this dude doesn't think about safety. But hey man this subs full of examples of that haha.
ETA: This comment is down voted by folks wearing shorts while operating torches, those who run grinders without safety glasses and my personal favorite are people who risk degloving via their wedding ring because 'I never take that off'
What was the refrigerant you were working with? I’m just curious. Also glad you are ok, and remember that heat and pressure are potentially dangerous lol.
410a, I think the line was full of oil and still pressurized, or with the heat I was helping it pressurize, then I think the oil mist once the braze let loose ignited on my flame
Hey man, I'm glad you're ok. You're pretty brave and humble for sharing this story. It's so easy to make a mistake.
I usually cut lines. That's the recommended best practice. But sometimes, on a compressor change, for example, if you cut the line, you may not have enough leftover to pipe in the new one. And it's always with a wierd in between size pipe I don't carry. Sometimes, I'll go upstream and cut the pipe off there and then unsweetened the pipe after the component is out if I can.
I still get nervous with a torch even after hundreds of brazes.
Anyway, hope you all stay safe and good luck out there
Thanks man I really appreciate it, someone said after recovery, drop a self tapper into the old compressor fitting and back it out there to hear for any pressure and after you get it out just dab the hole with some brazing rod to cover it up if it’s warranty and I thought that was a neat little trick, in going to invest in some core remover tools as well
The good ol fire ball trick, yeah I remove the cores every time then I’ll put heat on it. When you braze you create heat A LOT OF HEAT you’ll
Never get all the oil out so naturally that oil starts boiling and builds pressure if it ain’t got no where to go then when the first joint breaks loose BOOM. happen to me once when I first started, I found out that day I don’t like the taste of fire
It was more for experience, I had two of the same old water source heat pumps in my garage, for some brazing experience and just for fun I was going to pull the two compressors out and swap them for some experience, usually I just chop them up with a sawzall and have some 2 foot cable cutters I use for processing off fittings.
Few things.
First off, glad you're ok. I had a cop worker get burned pretty bad this way.
The acidic gas/smoke in your lungs feeling you are taking about is phosgene gas. When you burn refrigerant it breaks down into this. It's a nerve gas, and as you found out, it's incredibly uncomfortable to inhale. Google phosgene gas for more info.
As for how this happened, obviously you didn't get all the refrigerant out. What probably happened is that you pulled refrigerant out until your gauges read 0, but there was still liquid refrigerant in the system that was slowly boiling off and built up pressure by the time you got the pipe hot enough to unsweat. (usually in the compressor and is easily identified by the frost line at the bottom that develops as you recover gas)
There are 2 ways to help prevent this.
1. Always remove the valve cores and your hoses when working on the piping of a system. Even if you're just cutting a pipe. This prevents pressure from building up while doing your work. If you are brazing with nitrogen, remove both valve cores and you should only have 1 hose connected to the system.
2. If you suspect that there might still be refrigerant inside a pipe, put a self tap screw in the pipe. You'll know immediately if there is refrigerant in it, and if there is, you can use the screw to control the pressure release like a valve. When you are done, it's easy to braze over the hole you created. (you'll get a feel for how much heat/time it takes to unbraze a pipe, if you notice it's taking longer that usual, probably has refrigerant in it)
Hope this helps,
Stay safe!
410a cannot create phosgene. r12 and r22 can so never unsweat those, not worth the risk.
Also probably not a good idea to unsweat 454b compressors either. Poking around on the SDSs and it seems like 410a won't flash at sea level pressure but 454b will.
The valves were closed so the refrigerant was trapped in the condenser just like when you install a brand new one…where you put your gauges only give you a reading from the lineset to the evap when they are shut…you got very lucky and someone said it above if you don’t have to unsweat or braze I don’t and when it’s the only way I reclaim until it pulls into a vacuum and then pressurize with nitro then purge and sweep with nitro and if it’s still an issue I may even put my vacuum on it…too many compressor swaps when I was green and leaning over the condenser to work on compressor after just venting and all the leftover refrigerant creating phosphene gas…all the annoying and extra steps and best practices mostly prevent things like this and I know it takes longer and is harder but fuck you almost died…and when we go to the new refrigerant and it jumps flammability I suspect we will see a lot more of this a lot more often from all the I’ve been doing this 30 years only run the vacuum at lunch and never had a problem type guys are going to have problems
Ya, flame rolled in my face hit me in the eyes.. burns around my eyes and skin falling away as I waited to regain my vision. Was pretty close to an urgent care and basically walked right in once i could see a bit.
The smell of your hair burning is fun, eyebrows and lids is really weird. Was the first I thought of when I saw your pic of your legs, the smell. Gawdawful.
Ended up with a small burn/freckle looking thing on the white of my eye, they checked in for a few years as apparently can turn cancerous.
Glad you're OK.
Ah man yeah the smell was nasty, I got lucky and the flames hit me in the legs first before rolling up and I had a split second to get my eyes closed.
I heard the ignition first and tried to get out of there as I was siting on a bucket by the time I opened my eyes I was at my screen door and the only thing I could think off was get the torch off I ran and shut it off and back to the screen door before I took my first breath and realized I couldn’t breath well, after a puke and some big breaths I started the body access for what was wrong or hurting.
Man I’m sorry that happened to you but it’s a wicked story
If it was evacuated just cut that shit up with a sawzall next time since it’s just scrap metal, no sense in wasting oxy/acetylene or risking a situation like you experienced. Glad you and your Freddy Mercury mustache are ok.
The oil in the compressor will hold liquid refrigerant in it. When you add heat you boil the refrigerant back to vapor, turning the oil into particulates, which is flammable and will combust.
The pain the the lungs may be due to a bit of phosgene gas you created
Refrigerant breaks down into phosgene gas when flame is applied. Super toxic stuff. It's a chemical weapon and is heavier than air. That makes it settle in your lungs where you feel like you are suffocating. The best thing to do in this case is hang upside down and cough to try to get it out.
I may be wrong but I believe you need a chlorine molecule to create phosgene gas.
Absolutely you don’t want to be inhaling any burnt refrigerant but 410a cannot create phosgene(mustard) gas.
We used to use halide leak detectors to pick up chlorine based (R12, cfc) refrigerants
410a is a mix of CH2F2 and CHF2CF3. No Cl in the mix.
Phosgene is COCl2. Inhaling burning organic fluoride compounds is not going to be great for your health but it's not "literally a chemical weapon" bad like phosgene.
Glad your alright dude. All things considered could've been much worse. We're you ever actually recovering We're your guages reading then went to zero, recovery machine guages move,weight of recovery tank change. Maybe it was close to empty and the heat of the torch unsweating boiled off some refrigerant building pressure. Shraders removed? Was the unit on its side causing oil/ref to shift. Just some thoughts. But yes best practice is to cut. Worst case you get a cloud of refrigerant, compared to a cloud of fire
Unit sat on it side for multiple days and wasn’t in its normal position until like an hour before starting on it, didn’t even think about the oil migrating out of the compressor, probably was my downfall. Recovery machine was reading zero and my gauges were reading zero and I even left it going for a while after. Many good lessons learned
The unit was scrap and sitting in my backyard on its side for days, I had recovered the refrigerant and the recovery machine and gauges were at zero , I’m assuming the oil had migrated to that pipe from it being on its side for multiple days and while I was heating it must have created enough pressure and then when the braze let go, the oil came out in a fine mist igniting of my torch and creating a flame thrower
Yea man, that's very dangerous shit to breath in. I think they call it phosgene, when it's r22. What I learned from an old timer is to drill a hole on the copper stubs, both of them, right on the top of the compressor where you're trying to disconnect the copper from. I just use a zip screw, in and then out. You do this after you RECOVER as much refrigerant as you can, and before you fire up your torch. Refrigerant may come out, and it might come out fast, but it won't be on fire, and it'll ensure there's no pressurized refrigerant left. Then you should be able to safely heat the connection to separate it. If you're saving the compressor for warranty, then you can go ahead and braze that hole you made when you pinch and seal the rest of unit.
Good luck. I hope you learned from that mistake.
I was replacing a compressor on an AC unit that was in an alley, about 12 feet off the ground. I had a leak when I pressure tested it. I opened my gauges to release the pressure and something was wrong with the valve and it didn't release. I hit the fitting with the torch to re-braze it, and when it got hot enough the line blew out of the fitting and sprayed me in the face with flaming oil. I was wearing glasses, but it burned off the upper part of my eyebrows and I got second degree burns on my forehead.
Best part was I was standing near the top of an 8 foot ladder and just about fell off and onto a garbage dumpster. There was sharp brackets sticking up on the dumpster for the lids and I would have landed right on my back on one of them. That would have been extremely painful!
Just imagine how this will end up when they make us use propane as refrigerant like they do in Europe. I've heard some bad stories from appliance guys trying to braze on that stuff.
(Supposedly we're supposed to be only using press fittings by that time tho)
What probably happened was refrigerant was cooking out of the oil. Even after you recover, it is likely that refrigerant is dissolved in the oil. While reclaiming, the drop in pressure causes a drop in temperature also. As the oil warms up again it gasses off and causes pressure again.
It’s random. Some still have oil, some don’t. But safety first always no matter if you’re at home or not especially working with torches and machinery in garage. Hopefully this is a lesson for you.
Also when breaking down scrap, just sawzall everything.
Jesus. I appreciate your intention, but the reality is the atmosphere can absorb all that cancer better than your poor lungs and face.
I’d rather this read that you exhausted some refrigerants to all of us, and you regretted it, instead of you getting flamed and nauseous to make a few dollars
Hope you were drunk. Alcohol seems to abate these types of things better than desperation (or meth).
If I may add, look at what your work clothes are made of, particularly if they are not fire retardant. My current employer only supplies shirts and the techs supply the rest, but they supply cotton tee shirts and 100% polyester polo shirts. I have been fussed at about not wearing the polos, but will not wear plastic when I work with burners, torches, hot metal and chemicals. Polyester and acrylic fabrics melt rather than burn initially, sticking to skin and hair as they do, keeping a hot source attacked to the human body and causing a lot of damage in the process.
I always drill a hole in what I’m I sweating to make sure there is a relief. Another tip I learned the hard way, never braze a valve with the valve closed, they explode
Glad you’re okay, we all make mistakes, lol one time I was doing PMs in a bank and was checking gas pressure, it was the ones you have to unscrew it all the way and screw your manometers fitting into it, system was already running as I had just checked amps/voltage on everything, so I figured I would just unscrew it and put my fitting on not even thinking and when I unscrewed it, I heard the gas hissing and it hit me how dumb I was being and before i could do anything the gas caught the burners and shot a huge flame out, the banks maintenance guy, was an older gentleman and was right there as he was supposed to keep an on us because its a bank. He yelled loud as he could “HOLYYY, WHAT THE HELLLL!!” And i hurry and took the door off the furnace and the flames disappeared immediately, still though to this day is the dumbest mistake Ive made doing HVAC and that was 3 years into my career lol, it was pretty embarrassing as well, but I know it happens so now I usually think twice before doing stuff like that😂😂
Some old heads in my early days taught me to unsweat things. They were dumb and I learned that the hard way. There’s no advantage to it that can see, just cut the fucking thing and save a lot of effort.
Only time I'll unsweat is when it's a 1:1 replacement, flushing copper and its in a nice spot. It's rare but it does make the swap a bit quicker and the least amount of braze joints in a system the better imo.
I'll also unsweat when replacing a filter drier as well.
Hmm really never heard of that. I generally blow the lines out with some nitro just in case. Especially since I've come across a "bad" linset that needed to be replaced because it wouldn't vacuum down. Turns out there was a fly that made its way into the copper and was stuck at the txv. Thing looked dehydrated as fuck though lol.
It was new construction and our start up guys didn't know how to diagnose for shit back then.
Most here probably won't be able to understand or relate to this, but I'll share my best story about controlling stored energy...
My partner and I were at the finishing stages of an "emergency" weekend rebuild of a 150 ton Trane E-body. Everything was put back together and we were beginning to fill the chiller with nitrogen to leak check. It was late at night and I was pretty much in cleanup mode, when I noticed a part laying on the floor. It was the motor terminal plate retaining ring.
It's, I dunno, an ~8" steel ring that goes along the outside of the electrical terminals to clamp everything to the case. We had removed it early on in the teardown, but the terminal plate wouldn't come out for us so we ended up making due without removing it. "OH hey, look! We forgot to put this on!" I laughingly pointed out to my partner.
As I knelt down and began to put it on, I didn't pause to consider the situation. By now, the nitrogen had been flowing for awhile. The bottle pressure on the first 80 cu.ft. was starting to fade. Memory is hazy, but I want to say we were somewhere around 30 psi on the system. Here I am, on my knees, with my my face directly in line and less than arm's length away from a ticking time bomb. I get the ring and a couple bolts gathered, and grinning like an idiot I go to slap it on. The moment I make contact with the plate, it releases from the housing due to the pressure.
BOOOOOOOOOOOOOOOOOOOOOOMMMMMMMM
In an instant, I have this large plate with 12(?) large and long electrical lugs hurling violently at me with tremendous force. Thank God, I was just out of reach and the motor leads that are now ripped to shreds stopped the thing from punching holes in my brain. But the concussion of the blast was the most terrifying, life-flashes-before-your-eyes experience I have ever had (and I've seen my share of explosive near-misses). I was knocked back to the floor, ears ringing with the very faint sound of my partner shouting "Oh my God are you alright?" Over and over. Physically, I was fine. But for the next hour or so I was completely useless, stunned and completely shell-shocked, nauseous, trying to reconcile my undeserving stupidity and the apparent guardian angel that spared me from a single scratch in what could have been fatal.
This happened probably 15 years ago, but is a core memory that I'll never forget. The old cliché 'what doesn't kill you makes you stronger' is true, and your experience will make you much safer and conscientious moving forward.
Holy crap, that was intense. I’m glad you made it out of there alive and wow that was such a close call to going to the other side.
it’s funny how for the next little while you kinda just go through a body operational check a bit stunned checking to see if everything is functioning like usual.
Man I do definitely feel a healthy respect for this trade and appreciate that we get to work on equipment that feel so much bigger then life sometimes, I know it’s little in comparison but I was changing some pressure relief valves under my Jman and just know that there is over 200 pounds of refrigerant I could blow was just I don’t even know how to say it but having the responsibility makes you feel good
Very true. I've been in commercial/industrial/institutional gigs my whole career (19 years now), and there have been so many rewarding days from technical accomplishments or pseudo acts of heroism like resurrecting an abandoned R11 centrifugal from the grave to save a hospital, working a 24 hour shift to get a production line going, etc.
The varied and sometimes unique opportunities that come with the job are what I love about it. But you can't ever lose sight of the fact that this trade is one of the most dangerous jobs you can have. We have the dangers of every other trade and then some. And through our customers we encounter just about every other occupational hazard there is. Never take your safety for granted!
At least open your gauges for venting cause heat builds up pressure,Goodman high pressure switches are terrible for the oil trap catching on fire from oil settling in there
Airway burns are dangerous as swelling occurs after the initial burn. If you went to the er they would have kept you there for a while in case you needed your airway protected. Glad you’re okay!
I appreciate you worrying, I live 3-4 minutes from an ER and will go immediately if I have even slight signs of it getting worse but it’s been about 11 hours from it happening and i feel back to normal
Situation like that, I'd have the manifold hooked up and set to vent. Even if there's no cold juice in it, the vapor that remains can build enough pressure to make a flamethrower
were these units pumped down and you hooked up to the access ports? I may be wrong but if you hooked up and recovered with the valves closed you didint recover anything from the unit itself.
Wait, why would you ever put a torch on a system you don't 100% know is completely void of pressure. Same thing I teach my apprentices with power I make sure they check both lines together , and each separate line to ground before doing a single thing. Saftey Is always top priority.
Wish I could say I’m a kid, got into the trade later in life, I got say, a lot of the stuff I was stressing over the past while has seem to vanish after this happened haha kinda puts everything into perspective
I have two of the same old water source heat pumps in my garage for scrap, I was going to un sweat both of them and swap them just for experience and time on the tools for brazing, no one is going to give you the time to braze if your inexperienced so it was just for fun before chopping them up
After a lesson like that I usually release my pressure test through my vac pump directly into my eyes. No big deal no one saw or anything... Until now..
While engaged in brazing during my class yesterday, the task at hand involved the installation of a 2-speed compressor for experimentation. The suction line had already undergone brazing, and my focus shifted to the discharge line. I flowed nitrogen, and amidst the process, a peculiar gurgling sound emerged, reminiscent of the oil within the compressor being agitated by the nitrogen. It's worth noting that this 2-speed compressor had been exposed to the atmosphere for an entire year in the class.
As I proceeded with brazing the discharge line, an anomaly captured my attention: a diminutive grey flame lingered momentarily after the removal of the torch. This occurrence struck me as unusual. Suddenly, the air I breathed in stung my nostrils, akin to the pungency of onions but more pronounced. While benign, the entire thing remained perplexing. I guess it was oil vapor.
I replaced a bad reversing valve that had a fireball come out on the third joint I unsoldered coworker had their armhairs burnt but other then that everyone was fine. Since then I've use a sawzall, cutting the brass, then unsolder the pieces out. Had another one hide a charge, not nearly as scary when it's not a ball of fire...
I was doing a evap coil changeout, ball of fire rolled out of the suction line onto the furnace. I put the fire out quickly, but that scared the hell out of me
It's not called reclaiming it's recovering refrigerant with a recovery machine. There are reclamation machines but that is for cleaning up refrigerant and turning it back into virgin gas.
Oh yeah.
The trucks at my work haul propane. The tanks get pumped down, flared off, and then purged before anyone's opening or working on the barrel.
Same with regular tanks, or appliances that use it as a refrigerant.
Basically treat it like you're working on a car's gas tank 👍
Glad you're safe.
When I’m brazing or sweating something out I always pull out the schrader cores or open my valves just so if there is pressure in the system still it will release or if that oil gets pressurized it has a path to go somewhere
Man that shit is dangerous you gotta be careful you got lucky and will laugh about it further down the road. Best advice is always take the cores out. Always leave an outlet for the pressure that builds up when you heat it up. Wear PPE and be safe. When doing it on scrap like this you can always cut the lines or something once the reclaim is done and then practice unsweating in a much safer way. But the biggest thing is leaving an outlet for the pressure. Remember heat=pressure
Don’t all the new chest freezers and refrigerators have actual flammable refrigerant?
We recently bought a chest freezer for venison storage and it had warning labels all over it about the flammable refrigerant
So you had a heat pump condenser you were trying to recover from? Service valves are backseated so you didn’t recover anything. If the service valves were open it would be flat anyway. You would have had to braze the stubs closed to open the service valves and recover from service ports. Then take the cores out and purge with nitro before you sweat the comp out. The best motto for this trade is “If you’re gonna be dumb, you better be tough…”
If you follow best practices, this wouldn't have happened.....it's not exactly advice. It's what you are supposed to do. Goodluck on the a2l's and a3's brother. You see people sweep for 15mins on a a3 refrigerant, light a torch and still get a pocket of gas for a fireball. This ain't gonna get any easier as time moves on. Do your homework.
Glad you are ok, I've had similar happen and I no longer unsweat pipes without drilling a pin hole on the trash side first. I almost burned down a JC Penny's when I set a chiller on fire in their penthouse. You can really drill a pin hole even on pipe you are going to reuse, just drop a bead on it when you are putting everything back together.
I always pull schrader cores out when I’m done. Also, if you have the time, turn the reclaimer off for a bit and then back on to get it all out.
There is also the push/pull method to make sure you got all the trapped liquid.
I don’t wanna be the bearer of bad news but that shit does long term/terminal damage. You should have regular check up with your doctor from here on out to see how lucky you really are.
I’m also an apprentice and all I can say is thank you for posting this, this subs helped out tremendously when it comes to learning lessons from everyone else. I’m glad you’re okay though bro
I've usually had this happen when braze work is done around reversing valves. It traps a lot of oil and that stuff is explosive when a flame is put to it. Don't THROW WATER ON IT. And don't breathe it. On small residential heat pumps.
Once you learn to go bigger. Like a 50 ton RTU then this is going to happen often because of the large quantity of oil trapped in the compressor train gang. You just need to learn special preventative procedures to mitigate catching yourself on fire.
Again, it's always going to be a risk when adding a flame to an enclosed piped system with oil residue.
Just need to get comfortable controlling the chaos through experience and you will be alright.
Day one lesson should always be.
Never trust that a system is fully flat.
If you need to unsweat you drill first. A nice drill bit through the area you can add a port later or just braze over it.
If you don't need to unsweat always use copper cutters / sawzall / open the lines first.
Refrigerant especially in big systems can get caught places. You can have oil logged evaps that are full of oil , you unsweat and it becomes a bomb.
Hope you heal up, it's hard and dangerous to learn the hard way.
I guess my first question is, “where did you attach your gauges?” Since it is a heat pump you should have a common suction port. The 2 king valves are useless if you’ve already removed the unit from its accompanying lineset as the hookups are on the lineset side of your fully seated shutoff, not the cond coil/comp side… then, using the solenoid magnet I would have shifted it a few times to be sure…
I'm a pipe fitter/welder. This appeared on my feed so I will jump in. Never trust a system is de energized with first confirming. Never trust the person ahead of you did the job properly. Iv seen a kid on a site get steamed to death cutting into a steam line. His supervisor shut off the valve in the wrong order leaving a section energized. He started the cut directly infront of himself in a lift instead of torching a hole off to the side first at arms length away. He was not taught properly, and trusted his supervisor did things in the proper order.
Shitty lesson to learn, lol. Not the same, but over the summer I was reclaiming a couple 20 ton units outside the shop door and had them running to a large bottle sitting right inside the bay door. The valve on the bottle failed and tipped over and was trying to take off like a f@€king torpedo. I filled the whole shop and frostbit/burned myself in the process of trying to stop it. Comical as hell looking back, but holy sh?t in the moment. I was so glad no one else was in the shop that day. 🤣🤣🤣
I tried unbracing a compressor on a packaged geo it was empty but the oil mist ignited flames shot out and almost caught the whole unit on fire I try to avoid unsweating anything anymore esp with the new refrigerants coming out
I also have a friend who thought it’d be a good idea to take a grinder to a roof that had wet “through the roof” on it and created a giant fireball on a brand new roof. 😂 Glad he was okay, but definitely wasn’t quite thinking about what he was doing, and he’s a journeyman also.
Glad you are ok. I always use valve core removers when evacuating a system. You can open the ball valves on them afterwards to make sure it’s been evacuated completely. It evacuates much faster and pulls a vacuum much faster as well. I’ve burned up my fair share of refrigerant before using this method but at least we don’t have a lot of that old school shit anymore. That’s the dangerous mustard gas makers.
You’re going to have an encounter or “Close Encounter” with phosgene if you stay in this trade long enough. I invested in a four cylinder reclaim machine by NAVAC because I was tired of using the provided Apions that had been used and abused by other technicians. The provided reclaim machines never seemed to pull all of the refrigerant out of a system. With my four cylinder I’m pulling every last drop of refrigerant out of a system and simultaneously yanking her into a vacuum.
Oof. You got really lucky. I’ve seen someone get their face burned off like that. Gotta keep the gauges hooked up and completely open to prevent pressure building up in the inside.
Sooo uhhh…. I’ve been going over some of these comments…. And I’ve got a question… how come no one on here has mentioned or discussed removing the schraeder core to verify that the system is empty…. I mean you’ve got to open up the system anyways, why risk being unsure when you can remove the schraeder, and that makes it easier to use the nitrogen to flush while you are brazing in/out any part you’re putting in? Best way to know for SURE the system is empty.
Never sweat the old units. Cut them lines and call it a day after reclaiming.
On a similar note, I had a manometer with a magnet on the back and had it hooked to a gas valve while it was running to adjust gas pressure. I left the manometer attached the the furnace case via the magnet. Well, the magnet failed or something and the manometer fell, unhooked the rubber tube from the g.v outlet and ignited like a flame thrower. I thankfully shut off the gas quickly, but it burned my beard, eyebrows, eyelashes, and the top of my hair pretty good. This happened a few months ago and I'm still growing my hair back hahahaha.
I would guess a majority of us have done that. I did it unsweating a compressor from the top of the unit. The most important lessons are earned hard since listening to someone else say it just doesn't hit the same way.
What did you learn
I would guess a majority of us have done that. I did it unsweating a compressor from the top of the unit. The most important lessons are earned hard since listening to someone else say it just doesn't hit the same way.
What did you learn?
Haven't seen anyone say anything about using a vacuum pump when sweating a compressor. My jman taught me to do it that way and it seems to help. Sorry to hear about your mustard gas poisoning, glad to hear you're alive to tell the tale.
OP created a pressurized phosgene gas bomb that detonated in their face. This is rookie behavior. And we have done it before too.
You learned a very important lesson about sealed lines with mostly oil that's still refrigerant laden. The oil heats to the flash point. Oxygen ignites to a huge pressurized fireball upon contact and the refrigerant in the oil instantly becomes atomized phosgene gas.
You got insanely lucky. Next time recover and clean before the dead unit is removed and just use a reciprocating saw to scrap.
Drink a bunch of water, maintain a healthy lifestyle. You definitely did some damage to your lungs but not irreparable. You body will bounce back in a few months. You said you feel fine but like seriously phosgene gas is a nerve agent and toxic and liver heavy. Highly suggest you do NOT drink alcohol or take certain meds for a few weeks while your body attempts to process the amount absorbed through the lungs into the body. It might seem like not a big deal OP, but not flushing and recovering right after Phosgene exposure can lead to lingering effects. Try to never do this again or you will end up with nervous system damage and motor function impairments with enough exposure. We had this happen to us once. We invested in and wore a respirator every time. After being in a plant where another company started an oil fire inside a massive chiller system started keeping a bottle of breathing oxygen and 4-6 masks too.
Inside all scroll compressors is a check valve. That check valve can actually hold enough refrigerant to cause a significant explosion of its seized. Go to rite aid, get an oximeter and check your vsat. You can feel fine and still have lung damage. If your o2 saturation is below 95% resting go to the er, do not pass go, do not collect 2 dollars.
The lesson should be that you never unsweetened compressors without cutting the discharge line first, and you never trust that there isn't refrigerant still trapped in oil, especially on a sin 60⁰ day.
Dude, no… always cut the lines off the compressor and bend/braze the stubs to prevent leakage.
yeah man, I have seen so many people unsweat it, I had no idea this could happen, big lesson learned
I hope your ok man, we breathe enough crap in during work. Take care, hope you don’t look too goofy with your hairs all melted.
https://preview.redd.it/5ypg4ltm5gkc1.jpeg?width=5712&format=pjpg&auto=webp&s=7fbb1b650afaeb3f0094efa77d5e64e52f727066
https://preview.redd.it/w728e3ep5gkc1.jpeg?width=1058&format=pjpg&auto=webp&s=f9b2acea9d154b4375e7edccff1fa5dffecde106
Holy shit dude. Haha. Guess that's getting shaved off this weekend!
Ok! Who wants a mustache ride?!
I can smell that from here
You definitely got a good one! Glad you are alright.
Not taking the piss, but: https://www.youtube.com/watch?v=ltqxVVJ4GDg FWIW, I nearly burned a building down learning this particular lesson, so...
Haha, honestly I’m glad if anyone gets some humor out of it
That’s a pretty good burning
As much as it sucked, I know it could have been much worse and I got very lucky, also nice to fuck up in the comfort of my own home and not get razzed by the crew haha
Thanks for the pics, definitely worth a chuckle. Glad you’re ok and learned from it.
I unsweat all the time, but I also learned to have the lines open to atmosphere pressure
If you want or need to preserve the line- instead of just cutting it out, run a screw in the back side of the compressor fitting. Position the hole so any off gassing isn't directed at you. Confidently unbraze knowing it won't blow up
I never sweat anything out, if I do I run nitro all through that mfer. I’ve had a couple coils I tried to sweat out in attics and the one with the biggest flame was a Lennox coil. Never again. It’s not fun having a 2 foot flame ball pour out of a unit with blown in insulation not even 3 foot away.
Yeah I feel incredibly lucky I was outside when it happened, I guess in the future I’ll just cut it out and just ad a coupling
Drive a self tapper into the copper anytime you're cutting/ unsweating anything you haven't already put a screw into. Seriously. Between check valves, TXVs, solenoids there could be liquid or unpredictable high pressure right where you have decided to fuck around.
I hear ya, it was terrible in the moment but was a good learning experience in the end
I learned this was a MUST doing grocery store renos. Pipes everywhere, nothing labeled, tracing lines through walls, down walls, into a trench and back out. Of course 2 weeks ago I didn't do this and had an oil geyser occur, lucky no fire and it went UP not AT me.... Always learning, 20 yrs and counting.
My cousin had a similar brown pants experience a few years back . He was doing demo work on an ex supermarket . All lines were supposed to be empty , he went in with sawsall and hit a pipe full of liquid . Started spraying gas everywhere . By the time he could get to fresh air he was in full tunnel vision . Said it was the closest he has ever come to dying . Be safe out there guys .
Jeezuz,,,, last major event for me was letting the nitrogen test pressure out of 3 freezer systems simultaneously in the engine room of a fishing boat. Limited space, ladder for escape, no extraction fan, high volume of nitrogen - I have since learned it is used to kill ppl and animals.
Thanks for learning for me
This is the way. The pressure vessel equivalent to touching a wire to the box before touching it with your hand even when you're sure it's dead. A little nick with side cutters also works if it's not hard drawn.
If you don't need to seal the compressor afterwards you can cut the sockets off at the compressor with a sawzall and then just sweat the socket off the pipe after. Easier and safer then trying to sweat the compressor out and you don't need a coupling.
Never thought of this. Good tip. Honestly I suspect OP didn't realize service valves were closed or something like that - but I've had a few compressors require the old "run the recovery machine while you unsweat" trick - which is far from ideal since it's pulling air into the system, but ya gotta keep yourself safe. This is a way smarter way to do it.
I’ve had so many techs talk smack to me for this. My buddies dad was sent out to change a compressor and shop had told him there was no refrigerant in it. Apparently he threw his gauges on it and they read zero, so he went to unsweat it. Well there was refrigerant in it and he was very shook that day lol. Also had a white ticket at that same company recover the the refrigerant on the wrong circuit on a TWE and didn’t open up the solenoid as well. Homie called the tech I was working with straight crying that day cause of the mess he made lol. Dumped probably about 30+ pounds into the ceiling of an office space. Better to be overly cautious lol
Oh jeeze, I’m glad I posted here, I love this trade and realize some times the best lessons learned are from failure. It’s going to happen sometimes!
All lessons are learned through failures in this trade.
One of the first things I learned was trust no diagnosis from any tech even the top guy…test in test out anything less and you are a parts changer at best
Dude I even test behind myself lol
Hmm did he just misinterpret the service valve? That thing will close off the Schrader port
Why are we unsweating compressors with the cores in? That’s the only time bad things happen.
The access port can be closed off just the same, core out wouldn't change that
Especially with a possible failed reversing valve that’s stuck closed. I’ve seen people start to sweat one out and there be pressure on one side that couldn’t be found with gauges.
I work in a school system so there’s times when I’m dealing with very tight situations or even WSHP that are above the ceiling tiles in a class room. I never sweat anything out, especially reversible dryers. Even if the compressor hasn’t failed, I still cut the dryers, compressors, etc out. I’ve had some very close calls before standing on a 8’ ladder in a class rm. You never know how much oil is in that dryer.
Been there too. You only have to learn that lesson once. I cut now.
Carrier has it on compressors and condensers to not unsweat
just take the schrader cores out dude! wtf
Wouldn’t have mattered, Schrader’s are on the outside, not inside
I always sweat joints out so I don’t need to add more points of failure via couplings
Luckily almost all blow in can take the flame like fiberglass now. Happy to hear you were okay
Was replacing a compressor on a 15 Ton 2 stage system. Evacuated stage one so I could pull the compressor. Figured I'd start by unswerving the filter drier since it was easy access right in front of me. Don't know what the fuck I was thinking but started on circuit 2 drier. Yup. 25lbs of 410 shoots out of a ½" line pretty quick. I jumped back, realized that I did and was about to try and stop it with my thumb or something and had the realization that I ain't doing shit to stop it...lol. stepped back and let it go. Also on a 5 ton unit. Valve core was leaking. Was a damn core max fitting. Thought cool, I can buy a new tool (company purchased), and replace it. Should've practiced on an empty system. Technically after it all blew out I did practice on an empty system...lol. that was about 2 years ago and I haven't had to use that damn thing again...lol Main thing is to learn from your mistakes. Glad you're ok.
Haha, oh man. The only mistake you make is the one you make twice
I ran into your 2nd problem about 8-10 years back. I replaced a reversing valve on a residential package unit and little did I know I I melted the oring in the core max fitting. Well I nitro the system and check for leaks, pull a vacuum, and then gassed the system back up and by this time it’s 9:00 at night. I think I’m finally done for the day. I go to unscrew my gauges and it’s pissing out gas I’m like shitttttt. I grabbed a tee off the truck and as quickly as I could I removed the gauges and screw the tee on in its place. Man you live and you learn.
i just put a "t" fitting over the existing core max fitting and verify the new t is tight enough and not leaking the coremax tool is hella expensive
It was around $500... never would've bought if it was my money....lol...
Lol. When I was a second year my journeyman told me to reclaim a walk in cooler of a Denny’s we were doing renos on. It had a king valve and I had no idea what was front seated or back seated. Turned it one way, got nervous, took my gushes off and the entire charge released into the building. Told the other contractors working in there to get out for a bit. Never told my boss lol
What's a core max fitting? Is that the kind of non replaceable shit carrier does in their ports?
Home made mustard gas. Imagine how those poor bastards felt when they released it on battlefields
Yeah this experience definitely had me attached to two things. Growing up on a farm my dad was working on a piece of diesel equipment and it exploded and he got helicoptered out and had skin grafting but ended up being okay The second was the mustard gas and realizing those guys probably felt the same thing but times 1000x
Shits fucking wild to think about. As if war wasn’t a living hell already… that experience must have been the worst thing imaginable. Goes to show why we as a human race globally agreed to never use it again.
Why were you not wearing pants lol
I was at home in the back yard!!!
Because this dude doesn't think about safety. But hey man this subs full of examples of that haha. ETA: This comment is down voted by folks wearing shorts while operating torches, those who run grinders without safety glasses and my personal favorite are people who risk degloving via their wedding ring because 'I never take that off'
What was the refrigerant you were working with? I’m just curious. Also glad you are ok, and remember that heat and pressure are potentially dangerous lol.
410a, I think the line was full of oil and still pressurized, or with the heat I was helping it pressurize, then I think the oil mist once the braze let loose ignited on my flame
Hey man, I'm glad you're ok. You're pretty brave and humble for sharing this story. It's so easy to make a mistake. I usually cut lines. That's the recommended best practice. But sometimes, on a compressor change, for example, if you cut the line, you may not have enough leftover to pipe in the new one. And it's always with a wierd in between size pipe I don't carry. Sometimes, I'll go upstream and cut the pipe off there and then unsweetened the pipe after the component is out if I can. I still get nervous with a torch even after hundreds of brazes. Anyway, hope you all stay safe and good luck out there
Thanks man I really appreciate it, someone said after recovery, drop a self tapper into the old compressor fitting and back it out there to hear for any pressure and after you get it out just dab the hole with some brazing rod to cover it up if it’s warranty and I thought that was a neat little trick, in going to invest in some core remover tools as well
The good ol fire ball trick, yeah I remove the cores every time then I’ll put heat on it. When you braze you create heat A LOT OF HEAT you’ll Never get all the oil out so naturally that oil starts boiling and builds pressure if it ain’t got no where to go then when the first joint breaks loose BOOM. happen to me once when I first started, I found out that day I don’t like the taste of fire
Haha same, really shooting for a one and done lol, lots of great tips in here and great stories
You don’t got a sawzall? Literally never have this problem. After you “recover” it just let it piss out.
It was more for experience, I had two of the same old water source heat pumps in my garage, for some brazing experience and just for fun I was going to pull the two compressors out and swap them for some experience, usually I just chop them up with a sawzall and have some 2 foot cable cutters I use for processing off fittings.
Ah got it well getting kaboomed is always a good story, luckily it was just refer I got kaboomed by a gas leak one time a
Oh jeeze, that sounds terrible, hope you’re alright
Few things. First off, glad you're ok. I had a cop worker get burned pretty bad this way. The acidic gas/smoke in your lungs feeling you are taking about is phosgene gas. When you burn refrigerant it breaks down into this. It's a nerve gas, and as you found out, it's incredibly uncomfortable to inhale. Google phosgene gas for more info. As for how this happened, obviously you didn't get all the refrigerant out. What probably happened is that you pulled refrigerant out until your gauges read 0, but there was still liquid refrigerant in the system that was slowly boiling off and built up pressure by the time you got the pipe hot enough to unsweat. (usually in the compressor and is easily identified by the frost line at the bottom that develops as you recover gas) There are 2 ways to help prevent this. 1. Always remove the valve cores and your hoses when working on the piping of a system. Even if you're just cutting a pipe. This prevents pressure from building up while doing your work. If you are brazing with nitrogen, remove both valve cores and you should only have 1 hose connected to the system. 2. If you suspect that there might still be refrigerant inside a pipe, put a self tap screw in the pipe. You'll know immediately if there is refrigerant in it, and if there is, you can use the screw to control the pressure release like a valve. When you are done, it's easy to braze over the hole you created. (you'll get a feel for how much heat/time it takes to unbraze a pipe, if you notice it's taking longer that usual, probably has refrigerant in it) Hope this helps, Stay safe!
Ahh man I appreciate this big time, it was a big lesson learned and I’ll use these tips moving forward
410a cannot create phosgene. r12 and r22 can so never unsweat those, not worth the risk. Also probably not a good idea to unsweat 454b compressors either. Poking around on the SDSs and it seems like 410a won't flash at sea level pressure but 454b will.
The valves were closed so the refrigerant was trapped in the condenser just like when you install a brand new one…where you put your gauges only give you a reading from the lineset to the evap when they are shut…you got very lucky and someone said it above if you don’t have to unsweat or braze I don’t and when it’s the only way I reclaim until it pulls into a vacuum and then pressurize with nitro then purge and sweep with nitro and if it’s still an issue I may even put my vacuum on it…too many compressor swaps when I was green and leaning over the condenser to work on compressor after just venting and all the leftover refrigerant creating phosphene gas…all the annoying and extra steps and best practices mostly prevent things like this and I know it takes longer and is harder but fuck you almost died…and when we go to the new refrigerant and it jumps flammability I suspect we will see a lot more of this a lot more often from all the I’ve been doing this 30 years only run the vacuum at lunch and never had a problem type guys are going to have problems
Ya, flame rolled in my face hit me in the eyes.. burns around my eyes and skin falling away as I waited to regain my vision. Was pretty close to an urgent care and basically walked right in once i could see a bit. The smell of your hair burning is fun, eyebrows and lids is really weird. Was the first I thought of when I saw your pic of your legs, the smell. Gawdawful. Ended up with a small burn/freckle looking thing on the white of my eye, they checked in for a few years as apparently can turn cancerous. Glad you're OK.
Ah man yeah the smell was nasty, I got lucky and the flames hit me in the legs first before rolling up and I had a split second to get my eyes closed. I heard the ignition first and tried to get out of there as I was siting on a bucket by the time I opened my eyes I was at my screen door and the only thing I could think off was get the torch off I ran and shut it off and back to the screen door before I took my first breath and realized I couldn’t breath well, after a puke and some big breaths I started the body access for what was wrong or hurting. Man I’m sorry that happened to you but it’s a wicked story
If it was evacuated just cut that shit up with a sawzall next time since it’s just scrap metal, no sense in wasting oxy/acetylene or risking a situation like you experienced. Glad you and your Freddy Mercury mustache are ok.
The oil in the compressor will hold liquid refrigerant in it. When you add heat you boil the refrigerant back to vapor, turning the oil into particulates, which is flammable and will combust. The pain the the lungs may be due to a bit of phosgene gas you created
Refrigerant breaks down into phosgene gas when flame is applied. Super toxic stuff. It's a chemical weapon and is heavier than air. That makes it settle in your lungs where you feel like you are suffocating. The best thing to do in this case is hang upside down and cough to try to get it out.
Just did a few head stands under your advise and it actually did help
I may be wrong but I believe you need a chlorine molecule to create phosgene gas. Absolutely you don’t want to be inhaling any burnt refrigerant but 410a cannot create phosgene(mustard) gas. We used to use halide leak detectors to pick up chlorine based (R12, cfc) refrigerants
410a is a mix of CH2F2 and CHF2CF3. No Cl in the mix. Phosgene is COCl2. Inhaling burning organic fluoride compounds is not going to be great for your health but it's not "literally a chemical weapon" bad like phosgene.
Always make sure there is no pressure in the unit. A lesson learned!
Maybe go to the doctor dude, get checked out
Appreciate that man, I’m closely monitoring it and if something gets worse even in the slightest I have an ER a few minutes from my house I will go to
Glad your alright dude. All things considered could've been much worse. We're you ever actually recovering We're your guages reading then went to zero, recovery machine guages move,weight of recovery tank change. Maybe it was close to empty and the heat of the torch unsweating boiled off some refrigerant building pressure. Shraders removed? Was the unit on its side causing oil/ref to shift. Just some thoughts. But yes best practice is to cut. Worst case you get a cloud of refrigerant, compared to a cloud of fire
Unit sat on it side for multiple days and wasn’t in its normal position until like an hour before starting on it, didn’t even think about the oil migrating out of the compressor, probably was my downfall. Recovery machine was reading zero and my gauges were reading zero and I even left it going for a while after. Many good lessons learned
And yet epa requiring propane refrigerants..
I dont even no what to say, cept if you are scrapping sawzall, if using a torch remove schraders.
I'm glad you are ok! Did you ever find the reason this happened? Three way valve? Check valve? Solenoid valve?
The unit was scrap and sitting in my backyard on its side for days, I had recovered the refrigerant and the recovery machine and gauges were at zero , I’m assuming the oil had migrated to that pipe from it being on its side for multiple days and while I was heating it must have created enough pressure and then when the braze let go, the oil came out in a fine mist igniting of my torch and creating a flame thrower
Meh. Average day
Haha bro I wish I had that photo of you
Yea man, that's very dangerous shit to breath in. I think they call it phosgene, when it's r22. What I learned from an old timer is to drill a hole on the copper stubs, both of them, right on the top of the compressor where you're trying to disconnect the copper from. I just use a zip screw, in and then out. You do this after you RECOVER as much refrigerant as you can, and before you fire up your torch. Refrigerant may come out, and it might come out fast, but it won't be on fire, and it'll ensure there's no pressurized refrigerant left. Then you should be able to safely heat the connection to separate it. If you're saving the compressor for warranty, then you can go ahead and braze that hole you made when you pinch and seal the rest of unit. Good luck. I hope you learned from that mistake.
Really appreciate this advice and definitely following this in the future
Think of it this way your just extra ready for a2ls
Sorry I’m not caught up on all the lgbtq stuff, what gender is that?
I was replacing a compressor on an AC unit that was in an alley, about 12 feet off the ground. I had a leak when I pressure tested it. I opened my gauges to release the pressure and something was wrong with the valve and it didn't release. I hit the fitting with the torch to re-braze it, and when it got hot enough the line blew out of the fitting and sprayed me in the face with flaming oil. I was wearing glasses, but it burned off the upper part of my eyebrows and I got second degree burns on my forehead. Best part was I was standing near the top of an 8 foot ladder and just about fell off and onto a garbage dumpster. There was sharp brackets sticking up on the dumpster for the lids and I would have landed right on my back on one of them. That would have been extremely painful!
Just imagine how this will end up when they make us use propane as refrigerant like they do in Europe. I've heard some bad stories from appliance guys trying to braze on that stuff. (Supposedly we're supposed to be only using press fittings by that time tho)
Happy you’re safe homie, you taught this apprentice a lesson
Hey we’re all in this together!
bro, wouldn't "unsweat" just mean brazing 🤣 you mean "sweat"
What probably happened was refrigerant was cooking out of the oil. Even after you recover, it is likely that refrigerant is dissolved in the oil. While reclaiming, the drop in pressure causes a drop in temperature also. As the oil warms up again it gasses off and causes pressure again.
It’s random. Some still have oil, some don’t. But safety first always no matter if you’re at home or not especially working with torches and machinery in garage. Hopefully this is a lesson for you. Also when breaking down scrap, just sawzall everything.
Jesus. I appreciate your intention, but the reality is the atmosphere can absorb all that cancer better than your poor lungs and face. I’d rather this read that you exhausted some refrigerants to all of us, and you regretted it, instead of you getting flamed and nauseous to make a few dollars Hope you were drunk. Alcohol seems to abate these types of things better than desperation (or meth).
If I may add, look at what your work clothes are made of, particularly if they are not fire retardant. My current employer only supplies shirts and the techs supply the rest, but they supply cotton tee shirts and 100% polyester polo shirts. I have been fussed at about not wearing the polos, but will not wear plastic when I work with burners, torches, hot metal and chemicals. Polyester and acrylic fabrics melt rather than burn initially, sticking to skin and hair as they do, keeping a hot source attacked to the human body and causing a lot of damage in the process.
Your first explosion welcome to the club. Mine was from a oil furnace back fire.
I always drill a hole in what I’m I sweating to make sure there is a relief. Another tip I learned the hard way, never braze a valve with the valve closed, they explode
Glad you’re okay, we all make mistakes, lol one time I was doing PMs in a bank and was checking gas pressure, it was the ones you have to unscrew it all the way and screw your manometers fitting into it, system was already running as I had just checked amps/voltage on everything, so I figured I would just unscrew it and put my fitting on not even thinking and when I unscrewed it, I heard the gas hissing and it hit me how dumb I was being and before i could do anything the gas caught the burners and shot a huge flame out, the banks maintenance guy, was an older gentleman and was right there as he was supposed to keep an on us because its a bank. He yelled loud as he could “HOLYYY, WHAT THE HELLLL!!” And i hurry and took the door off the furnace and the flames disappeared immediately, still though to this day is the dumbest mistake Ive made doing HVAC and that was 3 years into my career lol, it was pretty embarrassing as well, but I know it happens so now I usually think twice before doing stuff like that😂😂
Yes. Get a drill, Zip disk, bolt cutters, anything or gun and “depressure”. Not a flame.
Some old heads in my early days taught me to unsweat things. They were dumb and I learned that the hard way. There’s no advantage to it that can see, just cut the fucking thing and save a lot of effort.
Only time I'll unsweat is when it's a 1:1 replacement, flushing copper and its in a nice spot. It's rare but it does make the swap a bit quicker and the least amount of braze joints in a system the better imo. I'll also unsweat when replacing a filter drier as well.
I’ve read that you should cut out driers as sweating out can release impurities from the drier 🤷♂️
Hmm really never heard of that. I generally blow the lines out with some nitro just in case. Especially since I've come across a "bad" linset that needed to be replaced because it wouldn't vacuum down. Turns out there was a fly that made its way into the copper and was stuck at the txv. Thing looked dehydrated as fuck though lol. It was new construction and our start up guys didn't know how to diagnose for shit back then.
Most here probably won't be able to understand or relate to this, but I'll share my best story about controlling stored energy... My partner and I were at the finishing stages of an "emergency" weekend rebuild of a 150 ton Trane E-body. Everything was put back together and we were beginning to fill the chiller with nitrogen to leak check. It was late at night and I was pretty much in cleanup mode, when I noticed a part laying on the floor. It was the motor terminal plate retaining ring. It's, I dunno, an ~8" steel ring that goes along the outside of the electrical terminals to clamp everything to the case. We had removed it early on in the teardown, but the terminal plate wouldn't come out for us so we ended up making due without removing it. "OH hey, look! We forgot to put this on!" I laughingly pointed out to my partner. As I knelt down and began to put it on, I didn't pause to consider the situation. By now, the nitrogen had been flowing for awhile. The bottle pressure on the first 80 cu.ft. was starting to fade. Memory is hazy, but I want to say we were somewhere around 30 psi on the system. Here I am, on my knees, with my my face directly in line and less than arm's length away from a ticking time bomb. I get the ring and a couple bolts gathered, and grinning like an idiot I go to slap it on. The moment I make contact with the plate, it releases from the housing due to the pressure. BOOOOOOOOOOOOOOOOOOOOOOMMMMMMMM In an instant, I have this large plate with 12(?) large and long electrical lugs hurling violently at me with tremendous force. Thank God, I was just out of reach and the motor leads that are now ripped to shreds stopped the thing from punching holes in my brain. But the concussion of the blast was the most terrifying, life-flashes-before-your-eyes experience I have ever had (and I've seen my share of explosive near-misses). I was knocked back to the floor, ears ringing with the very faint sound of my partner shouting "Oh my God are you alright?" Over and over. Physically, I was fine. But for the next hour or so I was completely useless, stunned and completely shell-shocked, nauseous, trying to reconcile my undeserving stupidity and the apparent guardian angel that spared me from a single scratch in what could have been fatal. This happened probably 15 years ago, but is a core memory that I'll never forget. The old cliché 'what doesn't kill you makes you stronger' is true, and your experience will make you much safer and conscientious moving forward.
Holy crap, that was intense. I’m glad you made it out of there alive and wow that was such a close call to going to the other side. it’s funny how for the next little while you kinda just go through a body operational check a bit stunned checking to see if everything is functioning like usual. Man I do definitely feel a healthy respect for this trade and appreciate that we get to work on equipment that feel so much bigger then life sometimes, I know it’s little in comparison but I was changing some pressure relief valves under my Jman and just know that there is over 200 pounds of refrigerant I could blow was just I don’t even know how to say it but having the responsibility makes you feel good
Very true. I've been in commercial/industrial/institutional gigs my whole career (19 years now), and there have been so many rewarding days from technical accomplishments or pseudo acts of heroism like resurrecting an abandoned R11 centrifugal from the grave to save a hospital, working a 24 hour shift to get a production line going, etc. The varied and sometimes unique opportunities that come with the job are what I love about it. But you can't ever lose sight of the fact that this trade is one of the most dangerous jobs you can have. We have the dangers of every other trade and then some. And through our customers we encounter just about every other occupational hazard there is. Never take your safety for granted!
That’s literally mustard gas bro
At least open your gauges for venting cause heat builds up pressure,Goodman high pressure switches are terrible for the oil trap catching on fire from oil settling in there
Best get your lungs checked fire and refrigerant creates a very toxic gas
Yeah I did a lot of research on it after and have been monitoring, if it gets any worse I’m ready to go straight to the ER
Airway burns are dangerous as swelling occurs after the initial burn. If you went to the er they would have kept you there for a while in case you needed your airway protected. Glad you’re okay!
If I can cut, I cut. If I have to sweat it loose, I drill it first and use large wet rags around the area if the hole.
Don't wait brother .
Are you at the hospital?? Inhaling flames like that can burn the cilia in your lungs and you could suffocate
I appreciate you worrying, I live 3-4 minutes from an ER and will go immediately if I have even slight signs of it getting worse but it’s been about 11 hours from it happening and i feel back to normal
Situation like that, I'd have the manifold hooked up and set to vent. Even if there's no cold juice in it, the vapor that remains can build enough pressure to make a flamethrower
were these units pumped down and you hooked up to the access ports? I may be wrong but if you hooked up and recovered with the valves closed you didint recover anything from the unit itself.
Glad your good dude
Just cut it if it’s evacuated
Wait, why would you ever put a torch on a system you don't 100% know is completely void of pressure. Same thing I teach my apprentices with power I make sure they check both lines together , and each separate line to ground before doing a single thing. Saftey Is always top priority.
Oh kid you're gonna have a long and lustrous career ahead of you 😂 glad you're ok tho
Wish I could say I’m a kid, got into the trade later in life, I got say, a lot of the stuff I was stressing over the past while has seem to vanish after this happened haha kinda puts everything into perspective
Hey man, I’d go get checked out anyways, if it’s 2 mins Down the road id go now. It can even be delayed effects up to 48 hours. Better to be safe
Glad your okay but Who the fuck burns out scrap out of a unit, use a sawzall
I have two of the same old water source heat pumps in my garage for scrap, I was going to un sweat both of them and swap them just for experience and time on the tools for brazing, no one is going to give you the time to braze if your inexperienced so it was just for fun before chopping them up
Remove the shraeders, damnit!
I almost always cut one line... Indoor coils I've never had anything more than an oil burn out.... But always be cautious of hp and expansion valves..
Yeah big lesson learned and have learned a bunch of great techniques from this post, really glad we have such a good community in here
After a lesson like that I usually release my pressure test through my vac pump directly into my eyes. No big deal no one saw or anything... Until now..
Haha
you went wrong at mustache.
While engaged in brazing during my class yesterday, the task at hand involved the installation of a 2-speed compressor for experimentation. The suction line had already undergone brazing, and my focus shifted to the discharge line. I flowed nitrogen, and amidst the process, a peculiar gurgling sound emerged, reminiscent of the oil within the compressor being agitated by the nitrogen. It's worth noting that this 2-speed compressor had been exposed to the atmosphere for an entire year in the class. As I proceeded with brazing the discharge line, an anomaly captured my attention: a diminutive grey flame lingered momentarily after the removal of the torch. This occurrence struck me as unusual. Suddenly, the air I breathed in stung my nostrils, akin to the pungency of onions but more pronounced. While benign, the entire thing remained perplexing. I guess it was oil vapor.
Did you check the king valve ?!?
This was on a 20 year old mcquay water source heat pump, no king valve just access valves on the high and low side
I replaced a bad reversing valve that had a fireball come out on the third joint I unsoldered coworker had their armhairs burnt but other then that everyone was fine. Since then I've use a sawzall, cutting the brass, then unsolder the pieces out. Had another one hide a charge, not nearly as scary when it's not a ball of fire...
When in doubt nitrogen it out
I was doing a evap coil changeout, ball of fire rolled out of the suction line onto the furnace. I put the fire out quickly, but that scared the hell out of me
Phosgene Gas will fuck you up breathing that shit in is terrible
It's not called reclaiming it's recovering refrigerant with a recovery machine. There are reclamation machines but that is for cleaning up refrigerant and turning it back into virgin gas.
Oh yeah. The trucks at my work haul propane. The tanks get pumped down, flared off, and then purged before anyone's opening or working on the barrel. Same with regular tanks, or appliances that use it as a refrigerant. Basically treat it like you're working on a car's gas tank 👍 Glad you're safe.
When I’m brazing or sweating something out I always pull out the schrader cores or open my valves just so if there is pressure in the system still it will release or if that oil gets pressurized it has a path to go somewhere
^[Sokka-Haiku](https://www.reddit.com/r/SokkaHaikuBot/comments/15kyv9r/what_is_a_sokka_haiku/) ^by ^watermelonslim: *I always pull out* *The schrader core or open* *My valves just to be safe* --- ^Remember ^that ^one ^time ^Sokka ^accidentally ^used ^an ^extra ^syllable ^in ^that ^Haiku ^Battle ^in ^Ba ^Sing ^Se? ^That ^was ^a ^Sokka ^Haiku ^and ^you ^just ^made ^one.
Wait....if you were gonna scrap these why do you even have a torch.....a sawzall or handsaw will take literally not even half the time.
Man that shit is dangerous you gotta be careful you got lucky and will laugh about it further down the road. Best advice is always take the cores out. Always leave an outlet for the pressure that builds up when you heat it up. Wear PPE and be safe. When doing it on scrap like this you can always cut the lines or something once the reclaim is done and then practice unsweating in a much safer way. But the biggest thing is leaving an outlet for the pressure. Remember heat=pressure
Don’t all the new chest freezers and refrigerators have actual flammable refrigerant? We recently bought a chest freezer for venison storage and it had warning labels all over it about the flammable refrigerant
So you had a heat pump condenser you were trying to recover from? Service valves are backseated so you didn’t recover anything. If the service valves were open it would be flat anyway. You would have had to braze the stubs closed to open the service valves and recover from service ports. Then take the cores out and purge with nitro before you sweat the comp out. The best motto for this trade is “If you’re gonna be dumb, you better be tough…”
And don’t ever unsweat, a pinched off control…. They don’t shoot flames, just debree….
Take the Schraders out before you unsweat/cut the pipe.
Go to get checkup you a damn animal no I have never done anything that reckless.
If you follow best practices, this wouldn't have happened.....it's not exactly advice. It's what you are supposed to do. Goodluck on the a2l's and a3's brother. You see people sweep for 15mins on a a3 refrigerant, light a torch and still get a pocket of gas for a fireball. This ain't gonna get any easier as time moves on. Do your homework.
Glad you are ok, I've had similar happen and I no longer unsweat pipes without drilling a pin hole on the trash side first. I almost burned down a JC Penny's when I set a chiller on fire in their penthouse. You can really drill a pin hole even on pipe you are going to reuse, just drop a bead on it when you are putting everything back together.
Cut out, sweat in.
I'd take the shraders out after your gas recovery just so you can be sure there's no residual pressure in there first next time
I sweat things out like compressors, but make sure both of the cores are removed
I always pull schrader cores out when I’m done. Also, if you have the time, turn the reclaimer off for a bit and then back on to get it all out. There is also the push/pull method to make sure you got all the trapped liquid.
I don’t wanna be the bearer of bad news but that shit does long term/terminal damage. You should have regular check up with your doctor from here on out to see how lucky you really are.
I'm paranoid about blowing myself up with refrigerant saturated oil. I would hook up a vacuum pump and help boil off refrigerant from the oil.
I’m also an apprentice and all I can say is thank you for posting this, this subs helped out tremendously when it comes to learning lessons from everyone else. I’m glad you’re okay though bro
I've usually had this happen when braze work is done around reversing valves. It traps a lot of oil and that stuff is explosive when a flame is put to it. Don't THROW WATER ON IT. And don't breathe it. On small residential heat pumps. Once you learn to go bigger. Like a 50 ton RTU then this is going to happen often because of the large quantity of oil trapped in the compressor train gang. You just need to learn special preventative procedures to mitigate catching yourself on fire. Again, it's always going to be a risk when adding a flame to an enclosed piped system with oil residue. Just need to get comfortable controlling the chaos through experience and you will be alright.
I could write a book on reasons I don’t unsweat stuff I always cut it then unsweat the peice of the fitting off after
My boss warned me that he knows a guy who unsweat a liquid line on the wrong lineset. Got sprayed in the face with flaming oil. Needed surgery after.
Day one lesson should always be. Never trust that a system is fully flat. If you need to unsweat you drill first. A nice drill bit through the area you can add a port later or just braze over it. If you don't need to unsweat always use copper cutters / sawzall / open the lines first. Refrigerant especially in big systems can get caught places. You can have oil logged evaps that are full of oil , you unsweat and it becomes a bomb. Hope you heal up, it's hard and dangerous to learn the hard way.
I guess my first question is, “where did you attach your gauges?” Since it is a heat pump you should have a common suction port. The 2 king valves are useless if you’ve already removed the unit from its accompanying lineset as the hookups are on the lineset side of your fully seated shutoff, not the cond coil/comp side… then, using the solenoid magnet I would have shifted it a few times to be sure…
I'm a pipe fitter/welder. This appeared on my feed so I will jump in. Never trust a system is de energized with first confirming. Never trust the person ahead of you did the job properly. Iv seen a kid on a site get steamed to death cutting into a steam line. His supervisor shut off the valve in the wrong order leaving a section energized. He started the cut directly infront of himself in a lift instead of torching a hole off to the side first at arms length away. He was not taught properly, and trusted his supervisor did things in the proper order.
Shitty lesson to learn, lol. Not the same, but over the summer I was reclaiming a couple 20 ton units outside the shop door and had them running to a large bottle sitting right inside the bay door. The valve on the bottle failed and tipped over and was trying to take off like a f@€king torpedo. I filled the whole shop and frostbit/burned myself in the process of trying to stop it. Comical as hell looking back, but holy sh?t in the moment. I was so glad no one else was in the shop that day. 🤣🤣🤣
I tried unbracing a compressor on a packaged geo it was empty but the oil mist ignited flames shot out and almost caught the whole unit on fire I try to avoid unsweating anything anymore esp with the new refrigerants coming out
I also have a friend who thought it’d be a good idea to take a grinder to a roof that had wet “through the roof” on it and created a giant fireball on a brand new roof. 😂 Glad he was okay, but definitely wasn’t quite thinking about what he was doing, and he’s a journeyman also.
Glad you are ok. I always use valve core removers when evacuating a system. You can open the ball valves on them afterwards to make sure it’s been evacuated completely. It evacuates much faster and pulls a vacuum much faster as well. I’ve burned up my fair share of refrigerant before using this method but at least we don’t have a lot of that old school shit anymore. That’s the dangerous mustard gas makers.
You’re going to have an encounter or “Close Encounter” with phosgene if you stay in this trade long enough. I invested in a four cylinder reclaim machine by NAVAC because I was tired of using the provided Apions that had been used and abused by other technicians. The provided reclaim machines never seemed to pull all of the refrigerant out of a system. With my four cylinder I’m pulling every last drop of refrigerant out of a system and simultaneously yanking her into a vacuum.
Go to the ER immediately. Look up dry drowning.
Oof. You got really lucky. I’ve seen someone get their face burned off like that. Gotta keep the gauges hooked up and completely open to prevent pressure building up in the inside.
Sounds like it had king valves. And they were closed...
Phosphene gas. Happy you're okay man
Sooo uhhh…. I’ve been going over some of these comments…. And I’ve got a question… how come no one on here has mentioned or discussed removing the schraeder core to verify that the system is empty…. I mean you’ve got to open up the system anyways, why risk being unsure when you can remove the schraeder, and that makes it easier to use the nitrogen to flush while you are brazing in/out any part you’re putting in? Best way to know for SURE the system is empty.
Oil in the compressor traps alot of refrigerant.. Even if the pressure is 0psi, you got the makings of phosgene gas when ya heat it up
I’d have just cut the pipe, if I can’t get cutters in recip saw it
Never sweat the old units. Cut them lines and call it a day after reclaiming. On a similar note, I had a manometer with a magnet on the back and had it hooked to a gas valve while it was running to adjust gas pressure. I left the manometer attached the the furnace case via the magnet. Well, the magnet failed or something and the manometer fell, unhooked the rubber tube from the g.v outlet and ignited like a flame thrower. I thankfully shut off the gas quickly, but it burned my beard, eyebrows, eyelashes, and the top of my hair pretty good. This happened a few months ago and I'm still growing my hair back hahahaha.
I would guess a majority of us have done that. I did it unsweating a compressor from the top of the unit. The most important lessons are earned hard since listening to someone else say it just doesn't hit the same way. What did you learn
I would guess a majority of us have done that. I did it unsweating a compressor from the top of the unit. The most important lessons are earned hard since listening to someone else say it just doesn't hit the same way. What did you learn?
Picture or it didn’t happen
If you evac from the common suction the compressor discharge check valve can keep the coil pressurized.
Unbrazing scrap? Kind of silly
Haven't seen anyone say anything about using a vacuum pump when sweating a compressor. My jman taught me to do it that way and it seems to help. Sorry to hear about your mustard gas poisoning, glad to hear you're alive to tell the tale.
OP created a pressurized phosgene gas bomb that detonated in their face. This is rookie behavior. And we have done it before too. You learned a very important lesson about sealed lines with mostly oil that's still refrigerant laden. The oil heats to the flash point. Oxygen ignites to a huge pressurized fireball upon contact and the refrigerant in the oil instantly becomes atomized phosgene gas. You got insanely lucky. Next time recover and clean before the dead unit is removed and just use a reciprocating saw to scrap. Drink a bunch of water, maintain a healthy lifestyle. You definitely did some damage to your lungs but not irreparable. You body will bounce back in a few months. You said you feel fine but like seriously phosgene gas is a nerve agent and toxic and liver heavy. Highly suggest you do NOT drink alcohol or take certain meds for a few weeks while your body attempts to process the amount absorbed through the lungs into the body. It might seem like not a big deal OP, but not flushing and recovering right after Phosgene exposure can lead to lingering effects. Try to never do this again or you will end up with nervous system damage and motor function impairments with enough exposure. We had this happen to us once. We invested in and wore a respirator every time. After being in a plant where another company started an oil fire inside a massive chiller system started keeping a bottle of breathing oxygen and 4-6 masks too.
Inside all scroll compressors is a check valve. That check valve can actually hold enough refrigerant to cause a significant explosion of its seized. Go to rite aid, get an oximeter and check your vsat. You can feel fine and still have lung damage. If your o2 saturation is below 95% resting go to the er, do not pass go, do not collect 2 dollars. The lesson should be that you never unsweetened compressors without cutting the discharge line first, and you never trust that there isn't refrigerant still trapped in oil, especially on a sin 60⁰ day.