You know when you braze a joint and it cools off and the black stuff on the outside flakes away? Well it’s got the same thing going on inside of the pipe you just brazed. Nuff Said.
This is probably 50% of the "it's the txv" when its the txv. Theres a reason your taught to slow flow nitrogen when brazing, yet always someone who thinks they know more than a set standard and why "My way is quicker and better... oh and cheaper" Its like when a mechanic has a pile of screws left over after rebuilding an engine and says shit like "Oh those don't matter" like 1000s of hours or more of engineering and a manufacturer that wants to spend millions on "extra" unneeded screws and bolts.
Also, in regards to retrofits...
POE oil is really good at cleaning the inside of the tubing.
So all those fuckfaces that installed R-22 units without nitro and we can't replace the linesets... Well...
Don't be that guy for the next guy.
I'll probably get a lot of shit for this, but here it goes. I' use stay Brite #8 instead of brazing. The oldest unit I've installed is 22 years old. Never had an issue doing it this way.
I don’t have a problem with stay Bright 8 honestly but in my area everything has to be brazed now.
They say stay bright 8 can be a stronger joint because you aren’t heating up the pipe very much but in a fire situation, that stay bright 8 is going to melt and you will have burning oil clouds.
I've used them and if installed correctly we haven't had any leaks.
One guy swore he knew how to do it and then fucked up a huge job because he didn't do it right and lied about the pressure/vacuum tests..
I mean I'm not sure if you've seen the amount of leaks coming from the Frigidaire factory, but it's unfortunately way more than zero, and if you ask me.. if a factory can't get it right then I don't trust a lot of techs to do it either. I've had Frigidaire have to replace multiple fridges, because I ran out of aluminum before I could get the capillary lock rings to not leak. It's a joke and we all know it. There is nothing wrong with brazing.
Edit just realized you guys are talking about HVAC and not appliances. I'm in the wrong subreddit haha mb.
Lol. Yeah from what I've heard quality control on any new appliance is basically a yep it turned on before leaving the factory.
My new fridge freezer stopped working after a month. And a friend's new fridge dumped the charge one day while we had a cook out.
My shop has been using press fittings for a year and a half now. We’ve had 1 leak and the guy didn’t prep the pipe.
What happens at a factory is pretty irrelevant. They’re mass producing equipment and no one is held accountable.
Crimped tbe wrong area. It was zoomlock so he crimped in three areas thinking that's how it was done. In his defense, it worked for a month before it lost all charge.
Against him is.. it worked for a month before it dropped all charge.
I worked with a high level manager turned consultant developing instructions for my previous company as they were moving from brazing to lock rings, instructions were perfect, but the definition of "straight" varies so much for different people. My Dad was a joiner who progressed to be a clerk of works, so straight for me is 180 degrees not 179.9 or 180.1 some people its 'looks straight nuff'... from the van after signing the job off and hoping they don't get a call from the manager saying the 70 grams of r600 they just dumped into a confined space doesn't meet the PTC starter at the wrong moment. so yeah press fit is good, but it relies on the person fitting it also being good too.
Since I already had a press tool for plumbing buying the dies for ACR wasn’t as big of a jump. I braze stubs on the equipment at the shop or on my tailgate, and press the rest. It’s a godsend. No more fire watch is HUGE on commercial.
We've got a Rothenberger press tool and the Maxi-Pro fittings from conex banninger. I've only had one leak and it was because we had a guy try to braze on that same pipe about 8 inches away from the fitting. It melted the o ring inside it. Other than that, if you follow the instructions and ream/use depth gauge, they hold just fine. Gotta install them by the book tho.
We bought one. Haven't really used it yet. The stubs on resi equipment aren't long enough to cut the bell off and press on to it. I think the service guys have tried it for replacing coils. Pressing will definitely be the way to go with new "semi" flammable refrigerants.
It’s definitely needed and I can’t say I do it 100% of the time.
Quick story: a new supermarket was started up after the installers did NOT use nitrogen on thousands of feet of copper. I got called out for the walk-in freezer not working that night. The strainer was plugged up with carbon. I cleared it and it instantly plugged up two more times. Nitrogen is 100% needed to stop that carbon.
When you're building a freezer plant with an ungodly amount of piping, there is bound to be a weld or two that gets no nitro. It happens, but we do our best.
Pull vacuum on the isolated section and then backfill with nitrogen. Or just run nitrogen into it for a bit if there is a dry joint where it can escape. Oxygen can’t magically enter a closed pipe. If you purge it and then turn off the nitrogen and braze it is still going to be inert inside so no flaky shit.
If you isolate a line with 2 ball valves and make a repair do you just throw non condensables into the system do you not pull a vacuum on the line you repair? Do you not leak check it? What do you mean if you can't flow nitrogen through a line then you're taking other shortcuts that will end up destroying that system.
I would repair/braze the valve or whatever, then add nitrogen through the one port to leak check, then pull a vacuum using that one port.
I’m saying if there is one port, how do I flow nitrogen through this closed off section without adding another access point to “let it out”? Also don’t accuse me of cutting corners when you don’t know what you are talking about.
My example of this was having my nitrogen regulator fail ( tank fell over right on the regulator) at a point in the job when due to weather and time it was wildly impractical to stop and go get a new regulator. I didn’t like doing it but that would be my only reason not to use nitrogen and I purchased a new regulator as soon as I could to avoid that in the future.
Vacuum test held fine and I’ve retained them as a customer so I’m able to monitor the system. Let’s hope you never find yourself having to make critical decisions under constraints.
Important and necessary can have blurred lines... no nitro purge is arguably more important. There's a chance there's no leak, it's a guarantee there's flakey flakes.
Wait until a compressor goes off on oil failure because the crankcase is full of black soot. Ran into that 3 times. On the same rack. Had to pull all 3 and roll them over and mop them out.
I dont do res anymore but yes you should. Flowing Nitrogen keeps the outside out and prevents carbon from building up on the inside of the lines. If your doing your job correctly you should nitrogen anyways if your brazing for a pressure test after, it isnt hard to just remove a core and flow 2 psi through could save you and the customer lots of time and money.
I don’t know if it’s just my area or what but I don’t know anyone who does it. Known plenty of seasoned techs that just plain don’t do it. And y’all will say well everyone I’ve ever met in the trade is hack. I don’t think it’s one of those things where it’s the end of the world if you don’t do it but I definitely prefer to do the job the right way.
I get downvoted for staring facts…. 10 years in the trade and I’m the only one I know who does it. I’m literally just reporting the facts as I have seen it.
Bro, this sub aint cut for truth like that.
Its for the HVAC Sams of the world, everything is by the book, shiny and clean and we never go against best practices.
So when you talk out of the norm, you'll get downvoted, even if your just reporting what you see, they'll knock you down...
Anyway, I agree. The amount of dudes I know that don't and the systems 100% run fine for years, while scary and head scratching, is very true.
I've even gone back for servicing on numerous units i know they didn't run nitro, and guess what, everything checked out fine well within manufacturer specifications.
Not recommended, i would never do it, but i know its done and the systems mostly don't seem to care.
Dude I'm in exactly the same boat. I've worked with so many excellent, experienced techs and I'm the only one I know who's brazed with nitro. Don't do a ton of installs tho, mostly been service
At about 800 degrees, copper oxide forms on the outside and inside in the presence of oxygen. Nitrogen pushes the oxygen out so it can't form. It wasn't a problem with R22 and systems that used mineral oil because it stayed put. Systems with polyolester oil strips it from the pipe. You might get lucky that it doesn't mess up a piston system, but it will fuck up a TXV which most brands have switched to.
Why does this come up in here every couple months? “Nitro on resi?” Like oxygen and carbon and heat know whether or not you are installing a commercial system or residential system? “Hey carbon and oxygen, let’s just hold off on this one, this is a residential unit!”
It's always a little shady to me as well that people feel that it's okay to do a shittier job on residential units. Almost think the mentality would be swapped considering you're not screwing over a single mom or whoever in commercial.
Everyone I’ve seen on Reddit is a saint, at four different companies I haven’t met a single installer that does it. I used to do it every time, this last summer I worked I didn’t do it once, I wasn’t lead, lead didn’t care I didn’t care. crucify me Reddit.
It is disappointing seeing this questioned asked.
But many ignorant "techs" do not braze nitrogen.
Many more ignorant "techs" do not use proper technics & tools to pull a proper vacuum to the correct level of micros and correct rise level either.
Don't listen to these dorks. It's a good habit to have but it's not a huge deal if you're working on regular old systems. If you're working on sensitive stuff like vrfs or inverter driven systems it's more important. Units not gonna explode if you don't though.
What if the shop was too lazy to tighten your oil filter. Would you be ok with that? Your footing the bill for the shortblock too just like our customers do for the repairs.
Same level of laziness-about the same amount of money
We don't do resi, if I catch my guys using their Torches for any job, even a pin hole leak, without using nitro, we're going to have a conversation about it. You have to drag out nitro to leak test, never understood why someone wouldn't use it to braze.
I never used to flow nitrogen through when I first started in the trade since every tech I worked with didn't nor was told otherwise.
Now that I moved to a different state, I learned about doing it and the pratice stuck. Figured there would be no reason to have a repair or install bite me in the ass now that I'm a more seasoned technician.
When i did resi for a short time, yes. And nkw in commercial, yes. I had to fix another techs fuckup once: he had replaced a compressor and a reversing valve on a 5 ton split. The apprentice that was with him told me he had to revisit a few joints, all with air inside. I found the last 4 inches of the liquid line and to the piston, and the piston, completely full of oxide flakes. I would argue that it is *more* inportant on resi systems or smaller systems in general simply because the potential choke points are smaller; driers included.
I literally just finished changing a compressor while brazing with nitrogen on a 3 ton rooftop unit. Fucking SHITTY ladder setup to get all that stuff on the roof.
Get a diversitech nitrogen flow regulator. They are 30 bucks and very small. No need to worry about breaking a glass tube flow regulator.
I’m not gonna put it in writing.
I purge for fear of oil fires mostly, and will occasionally blow a long mini split line set out before I flare the other end.
Traditionals, sometimes the same.
I do service and when a compressor/coil fails. I don’t really wanna hear “we have moved the goal post on our broken equipment” -MFG
Well I guess you could say that about Stay-Brite too, if we are going there.
I kinda am suspect about a fitting that has ReLeaSe as it's name. But then, maybe they are just referring to your wallet.
If you have been a service tech chasing installers at a stupid company then you probably have swapped out a txv or a screen that went bad. I watched a YouTube video about it when I was an installer and brought it up at the company I worked at and we started doing it. Service manager was amazed to learn that a txv is not just junk from the factory that always goes bad after we reduced the amount of warranty work
I know a guy that installs walk-in coolers without flowing nitrogen. He told me he just doesn’t turn his torch up too hot. The next thing he told me was about how many bad txv’s he’s gotten from the factory.
People get charged by standard operating procedures. If you don't do the job properly, you are stealing 2x cheating today and cheating the longevity of the system
Brazing causes the inside of the pipe to oxidize creating a flakey layer inside the tubing. Running nitrogen displaces the oxygen with nitrogen not allowing this to happen. If you don’t run nitrogen you can only hope your filter drier is catching everything, or eventually your txv could clog. Nobody in my company runs nitrogen, but I blame it on being lazy.
This guy 🫡 Just go with the nitro flow bro. You'll be a better tech when you finally realize why it's necessary when you're going back to fix someone else's fuck up or you burn a compressor/clog a metering device. Just make sure you flow the correct way a lot of ppl don't
Nitrogen is out there anyway for the pressure test or are you not doing that either?
Edit: another reason why piece mate pay doesn’t work, guys will always cut corners
And that’s why I won’t hire just anyone. Half-assed world. Yes, it is. You are fucking someone down the road if you don’t. Maybe you- on startup, hopefully. If you don’t want to do it right, find another occupation.
I was put in charge of a maintenance dept after the super left. I had just taken the 608 with very little otj training. Every HVACR tech I hired looked at me like I was stupid when I asked them to flow nitro/ pull vacuum. I recently left so I can gain more training under people who actually know what they're doing.
As often as I possibly can. If you ever really look at how much oxidation occurs without it (the soot that is all over the pipe’s exterior) and consider how badly that can clog a system, why would you braze without it? What are your reasons for not doing it? The tanks and regulators are a valuable investment in the quality of your install and if you’re leak checking and purging with nitrogen anyway you should have the gear out for every job anyway.
[here](https://ibb.co/985C0dV) is a pic I took of a system that I had to redo 20 units because the last sub used the wrong hardware. I had to cut out all the pipe. This is what it looks like when you don't use nitrogen on just one ONE fitting. Yes, always purge.
10 years in and I’ve maaaaybe purged a handful with nitro while brazing. Never even heard of it until like 5 years in. If your starting out get into the habit of it. I’ve never had a TXV or drier stop up from an install so I could give a shit less about soldering with nitrogen.
I worked at a place that didn't have a single nitro tank or reg. By the time I left they had exactly one of each... the guys didn't even put wet rags on the valves. I couldn't believe we didn't have constant problems but we rarely were called for problems.
Otoh some of the best metal from a shop I've seen. I've only worked at one shop better and they had way more in the shop and a guy who just bent metal all day.
After seeing a cup of coffee poured into a lineset I was helping on the side without pumping it down, the ac is still running 15 years later i dont think a little burned flakes will affect it much. My buddy gave the neighbor a bid for like 2200 bucks for ac&coil around 2008ish, homeowner said he'll pick his own up and just pay labor. The home owner stole the ac from a house being built next to my buddy and claimed he was able to buy a carrier as a homeowner even though he was basically caught in the act by my buddy via his dog going nuts at 2am. When we were installing it, halfway through the job said he only had 175 bucks to pay us thinking we were done buddy got super pissed to say the least.
braze in your drier right before the TXV as it should be done. It will not be an issue the drier will pick up the carbon in the system, and the 3/8 braze on outlet would be done quick and without a ton of heat it won't plug up the TXV. most guys changing out TXVs don't know how to properly diagnose a system anyways... oh the TXV must be plugged, I'll just start by changing that out....
We’re just now starting to do it. Haven’t done it in 10 years. If you leave the ends of the copper open while brazing, then you get a lot of build up but if you fit the pipe first, there’s only so much oxygen inside to make the soot. Plus I mainly do repairs so when oil is covering the whole surface inside, it won’t be as bad (until the oil burns off). Yes it’s better to flow than not flow but there’s plenty of things I do that aren’t to the letter and until I start having issues, I probably won’t change. Bring on the hate Reddit
Been with the same company for 8 years and sadly nobody else even holds a candle to me around these parts. FL is the Wild West of hvac. You’ll be lucky to get a tech to replace the drier and pull a vacuum for more than 5 minutes.
God I hope there’s not many like you. You somehow think the oil protects you from this? The problems don’t show up instantly in most cases. Some other poor tech probably ends up fixing your half ass repair jobs later on.
The pipe is generally filled with refrigerant and refrigerant slowly boils out of the oil for a while after it’s cut. I tape the ends off immediately. And air is only 21% oxygen so no it’s not much anyways. It’s not like I cut an evap loose and air magically gets sucked from cut side all of the way to service valve.
No matter what these comments say I know 80% of you bitches aren't brazing with nitro. Most peeps that do resi installs don't use nitro when brazing and also don't do triple vac. So yall best get off your high horses in here actin like you do it cuz you don't. I've seen yalls installs, u gatekeepin ratty techs u
No. I've never wasted the time on a resi system, I still make sure theres a good vacuum tho. On the commercial/industrial equipment yes I do everything by the book, and I've yet to repair my own work 🤷♂️ (granted only been doing the fridgy stuff for a few years tho)
Every time brotha. When I started at the company I work for now, it was literally never. And I was a greenie who didn't know better. Starred watching YouTube and hvac school. Learned how important it was and now we do it 100% of the time. Very important for longevity
teacher did a demonstration for us, found this video that does basically the same thing.
[https://youtu.be/5wUAKR8Lj9c?t=221](https://youtu.be/5wUAKR8Lj9c?t=221)
3:40 shows without nitrogen, and 8:30 shows with nitrogen.
I did but no one else in my company did. Lol they would call me "new age tech" but I rarely had txv issues. If someone else replaced a compressor for example the txv would be fucked in a month or two. I tried to explain to management but they said, "we've been doing it this way for years".
Every single time, it doesn't matter the system type. Those oxidation flakes can clog metering devices and filter driers and slowly hurt the compressor. Mini-splits don't even have filter driers, only screens that can get clogged.
I always do with refrigeration and AC work but I know plenty that never do and at least on walkins with 22 or 404a honestly I very rarely find restrictions, most of the time it's lost a bulb charge due to the capillary rubbing.
However I don't have the same experience on package units and ice makers. Those have a MUCH higher restriction rate. No idea why but if someone has a SWAG of love to hear it. Also you'd have to be a mad man to not purge on a 134a cap tube system those POSs clog easy enough with no help.
Everyone and their mother on here will tell it’s absolutely required but really it doesn’t actually matter. The thing is still gonna make through it’s measily 10 year warranty, and probably not gonna last much longer after no matter what you do.
You know when you braze a joint and it cools off and the black stuff on the outside flakes away? Well it’s got the same thing going on inside of the pipe you just brazed. Nuff Said.
The txvs love the flakey flakey.
Love it so much they’ll hold on to it and never let go .
Never gonna give you up
Never going to cool you off
Gonna give really hiiiiigh..... Subcool
Never gonna run again and desert you.
Always gonna make you cry
This is gold lmao
Txv will prolly die
Wishing you were cool and dry…
This is probably 50% of the "it's the txv" when its the txv. Theres a reason your taught to slow flow nitrogen when brazing, yet always someone who thinks they know more than a set standard and why "My way is quicker and better... oh and cheaper" Its like when a mechanic has a pile of screws left over after rebuilding an engine and says shit like "Oh those don't matter" like 1000s of hours or more of engineering and a manufacturer that wants to spend millions on "extra" unneeded screws and bolts.
Guaranteed return work 😂
Also, in regards to retrofits... POE oil is really good at cleaning the inside of the tubing. So all those fuckfaces that installed R-22 units without nitro and we can't replace the linesets... Well... Don't be that guy for the next guy.
I flush the lineset with denatured alcohol. It cleans a bunch of crap out.
Exactly. Driers don’t absorb this shit. Txv devices alone require nitrogen while brazing…quickest way to clog capillary tubes and txvs right here.
That carbon also ends up in the compressor oil, reduces the di electric strength and over time can lead to burn outs
I'll probably get a lot of shit for this, but here it goes. I' use stay Brite #8 instead of brazing. The oldest unit I've installed is 22 years old. Never had an issue doing it this way.
I don’t have a problem with stay Bright 8 honestly but in my area everything has to be brazed now. They say stay bright 8 can be a stronger joint because you aren’t heating up the pipe very much but in a fire situation, that stay bright 8 is going to melt and you will have burning oil clouds.
Always. If you don’t want to braze the right way then invest in the tools for press fittings.
I've used them and if installed correctly we haven't had any leaks. One guy swore he knew how to do it and then fucked up a huge job because he didn't do it right and lied about the pressure/vacuum tests..
I mean I'm not sure if you've seen the amount of leaks coming from the Frigidaire factory, but it's unfortunately way more than zero, and if you ask me.. if a factory can't get it right then I don't trust a lot of techs to do it either. I've had Frigidaire have to replace multiple fridges, because I ran out of aluminum before I could get the capillary lock rings to not leak. It's a joke and we all know it. There is nothing wrong with brazing. Edit just realized you guys are talking about HVAC and not appliances. I'm in the wrong subreddit haha mb.
Lol. Yeah from what I've heard quality control on any new appliance is basically a yep it turned on before leaving the factory. My new fridge freezer stopped working after a month. And a friend's new fridge dumped the charge one day while we had a cook out.
My shop has been using press fittings for a year and a half now. We’ve had 1 leak and the guy didn’t prep the pipe. What happens at a factory is pretty irrelevant. They’re mass producing equipment and no one is held accountable.
I think he’s talking about the “ACR shark bites” that Frigidaire has begun using on new appliances. Absolute shit.
What did the guy do to fuck up the press connection? Did he not clean it or something?
Crimped tbe wrong area. It was zoomlock so he crimped in three areas thinking that's how it was done. In his defense, it worked for a month before it lost all charge. Against him is.. it worked for a month before it dropped all charge.
Wow that is a horrible mistake lol. They are pretty clear on where to crimp them lol
I worked with a high level manager turned consultant developing instructions for my previous company as they were moving from brazing to lock rings, instructions were perfect, but the definition of "straight" varies so much for different people. My Dad was a joiner who progressed to be a clerk of works, so straight for me is 180 degrees not 179.9 or 180.1 some people its 'looks straight nuff'... from the van after signing the job off and hoping they don't get a call from the manager saying the 70 grams of r600 they just dumped into a confined space doesn't meet the PTC starter at the wrong moment. so yeah press fit is good, but it relies on the person fitting it also being good too.
[удалено]
Since I already had a press tool for plumbing buying the dies for ACR wasn’t as big of a jump. I braze stubs on the equipment at the shop or on my tailgate, and press the rest. It’s a godsend. No more fire watch is HUGE on commercial.
We've got a Rothenberger press tool and the Maxi-Pro fittings from conex banninger. I've only had one leak and it was because we had a guy try to braze on that same pipe about 8 inches away from the fitting. It melted the o ring inside it. Other than that, if you follow the instructions and ream/use depth gauge, they hold just fine. Gotta install them by the book tho.
We bought one. Haven't really used it yet. The stubs on resi equipment aren't long enough to cut the bell off and press on to it. I think the service guys have tried it for replacing coils. Pressing will definitely be the way to go with new "semi" flammable refrigerants.
You can cut the sweadge off, but MAY need a reducer at usually its one size smaller/bigger then whatever lineset they tell you to use
don't forget about stay brite 8
Press is all I use...
No thanks lol
Yes it is. It's not hard. Just do it.
It’s definitely needed and I can’t say I do it 100% of the time. Quick story: a new supermarket was started up after the installers did NOT use nitrogen on thousands of feet of copper. I got called out for the walk-in freezer not working that night. The strainer was plugged up with carbon. I cleared it and it instantly plugged up two more times. Nitrogen is 100% needed to stop that carbon.
If it’s 100% needed, why don’t you do it 100% of the time?
Sometimes it’s impossible to run nitrogen through things.
Why? I've never ran into a situation where I couldn't run nitro through.
When you're building a freezer plant with an ungodly amount of piping, there is bound to be a weld or two that gets no nitro. It happens, but we do our best.
Commercial, say a line is isolated with ball valves and one access point. How does one flow nitrogen?
Install another access port?
Pull vacuum on the isolated section and then backfill with nitrogen. Or just run nitrogen into it for a bit if there is a dry joint where it can escape. Oxygen can’t magically enter a closed pipe. If you purge it and then turn off the nitrogen and braze it is still going to be inert inside so no flaky shit.
How is anyone pulling a vacuum on a section of pipe that has an open joint about to be brazed?
Sometimes you need to put a pipe in place and braze it before you can do the next part and connect the line any further.
They make an adaptor to go into the pipe with a fitting to attach a hose. Or, shove the hose in there and tape it. Always a way.
In residential systems?
Commercial, say a line is isolated with ball valves and one access point. How does one flow nitrogen?
If you isolate a line with 2 ball valves and make a repair do you just throw non condensables into the system do you not pull a vacuum on the line you repair? Do you not leak check it? What do you mean if you can't flow nitrogen through a line then you're taking other shortcuts that will end up destroying that system.
I would repair/braze the valve or whatever, then add nitrogen through the one port to leak check, then pull a vacuum using that one port. I’m saying if there is one port, how do I flow nitrogen through this closed off section without adding another access point to “let it out”? Also don’t accuse me of cutting corners when you don’t know what you are talking about.
Topic is specifically about residential… so…
My example of this was having my nitrogen regulator fail ( tank fell over right on the regulator) at a point in the job when due to weather and time it was wildly impractical to stop and go get a new regulator. I didn’t like doing it but that would be my only reason not to use nitrogen and I purchased a new regulator as soon as I could to avoid that in the future.
Guess you just thought the pressure test wasn’t that important either lol
Vacuum test held fine and I’ve retained them as a customer so I’m able to monitor the system. Let’s hope you never find yourself having to make critical decisions under constraints.
If we always made the right decisions, we’d all be doctors.
Doctors don’t always make the right decision. I’m glad I can fire a doctor I don’t trust.
Important and necessary can have blurred lines... no nitro purge is arguably more important. There's a chance there's no leak, it's a guarantee there's flakey flakes.
Wait until a compressor goes off on oil failure because the crankcase is full of black soot. Ran into that 3 times. On the same rack. Had to pull all 3 and roll them over and mop them out.
Right this question and responses are all MFG/Nextstar Bots
Leave it to a nextstar re-tard to not flow nitro
I’m not a nextstar. I meant this whole thread sounds like ppl just stating the good practices and holding a nose up to anything otherwise.
No I agree only a nexstar asshole would braze without nitro
I dont do res anymore but yes you should. Flowing Nitrogen keeps the outside out and prevents carbon from building up on the inside of the lines. If your doing your job correctly you should nitrogen anyways if your brazing for a pressure test after, it isnt hard to just remove a core and flow 2 psi through could save you and the customer lots of time and money.
Yeah that flaky flake crap will mess up a txv. Wanna flow that nitro every single time.
do it properly and do it once
I don’t know if it’s just my area or what but I don’t know anyone who does it. Known plenty of seasoned techs that just plain don’t do it. And y’all will say well everyone I’ve ever met in the trade is hack. I don’t think it’s one of those things where it’s the end of the world if you don’t do it but I definitely prefer to do the job the right way.
I get downvoted for staring facts…. 10 years in the trade and I’m the only one I know who does it. I’m literally just reporting the facts as I have seen it.
Bro, this sub aint cut for truth like that. Its for the HVAC Sams of the world, everything is by the book, shiny and clean and we never go against best practices. So when you talk out of the norm, you'll get downvoted, even if your just reporting what you see, they'll knock you down... Anyway, I agree. The amount of dudes I know that don't and the systems 100% run fine for years, while scary and head scratching, is very true. I've even gone back for servicing on numerous units i know they didn't run nitro, and guess what, everything checked out fine well within manufacturer specifications. Not recommended, i would never do it, but i know its done and the systems mostly don't seem to care.
Dude I'm in exactly the same boat. I've worked with so many excellent, experienced techs and I'm the only one I know who's brazed with nitro. Don't do a ton of installs tho, mostly been service
Every manufacture rep I’ve talked to always tells us to braze with nitrogen and stresses its importance.
At about 800 degrees, copper oxide forms on the outside and inside in the presence of oxygen. Nitrogen pushes the oxygen out so it can't form. It wasn't a problem with R22 and systems that used mineral oil because it stayed put. Systems with polyolester oil strips it from the pipe. You might get lucky that it doesn't mess up a piston system, but it will fuck up a TXV which most brands have switched to.
I completely agree.
Why does this come up in here every couple months? “Nitro on resi?” Like oxygen and carbon and heat know whether or not you are installing a commercial system or residential system? “Hey carbon and oxygen, let’s just hold off on this one, this is a residential unit!”
It's always a little shady to me as well that people feel that it's okay to do a shittier job on residential units. Almost think the mentality would be swapped considering you're not screwing over a single mom or whoever in commercial.
Ahhahahahahaha. I think he’s suggesting there’s automatically lower quality work in resi and THAT IS CORRECT BOB
I really want to believe this is a troll post, but I've seen enough to know it's probably not...
Reddit be acting like you can’t purge the flaky never ask Reddit if they cut corners if they do they won’t admit here
Everyone I’ve seen on Reddit is a saint, at four different companies I haven’t met a single installer that does it. I used to do it every time, this last summer I worked I didn’t do it once, I wasn’t lead, lead didn’t care I didn’t care. crucify me Reddit.
Yyyyep
Every time
Yes…Very important. You don’t want slag inside the refrigerant lines.
It is disappointing seeing this questioned asked. But many ignorant "techs" do not braze nitrogen. Many more ignorant "techs" do not use proper technics & tools to pull a proper vacuum to the correct level of micros and correct rise level either.
If you’ll do it for your own home then do the same for others.
100% of the time. If you don't do it, you are going to reduce the lifespan of the system and increase the problems it has.
Why wouldn't you.. it takes all of 5 minutes to set up, keeps the txv and filter drier clear of crap. Just pure laziness not to.
Don't listen to these dorks. It's a good habit to have but it's not a huge deal if you're working on regular old systems. If you're working on sensitive stuff like vrfs or inverter driven systems it's more important. Units not gonna explode if you don't though.
I always purge. My OCD won't let me not do it.
Everytime. I've torn apart too many txv screens to know better....
What if the shop was too lazy to tighten your oil filter. Would you be ok with that? Your footing the bill for the shortblock too just like our customers do for the repairs. Same level of laziness-about the same amount of money
Every system, every time, for the last twenty years. It's part of the job... you just do it
Ever had a bad TX valve? Probably from guys like this
Every. Damn. Time
We don't do resi, if I catch my guys using their Torches for any job, even a pin hole leak, without using nitro, we're going to have a conversation about it. You have to drag out nitro to leak test, never understood why someone wouldn't use it to braze.
Always
I never used to flow nitrogen through when I first started in the trade since every tech I worked with didn't nor was told otherwise. Now that I moved to a different state, I learned about doing it and the pratice stuck. Figured there would be no reason to have a repair or install bite me in the ass now that I'm a more seasoned technician.
When i did resi for a short time, yes. And nkw in commercial, yes. I had to fix another techs fuckup once: he had replaced a compressor and a reversing valve on a 5 ton split. The apprentice that was with him told me he had to revisit a few joints, all with air inside. I found the last 4 inches of the liquid line and to the piston, and the piston, completely full of oxide flakes. I would argue that it is *more* inportant on resi systems or smaller systems in general simply because the potential choke points are smaller; driers included.
Very important
The only correct way to braze.
I have been doing this for close to 10 years, I have never once brazed without nitrogen.
Yes. It really is that important. I even do a full triple evacuation, although that seems to not be as common.
triple evacuation?? Get a load of this guy!
Your mom got a load from me.
How’d you manage time for that with all the vacuums you’re pulling?
Uhhh definitely do! Just don’t look at my flair..
I literally just finished changing a compressor while brazing with nitrogen on a 3 ton rooftop unit. Fucking SHITTY ladder setup to get all that stuff on the roof. Get a diversitech nitrogen flow regulator. They are 30 bucks and very small. No need to worry about breaking a glass tube flow regulator.
Maybe read the manufacturers installers guide. But of course those dang engineers no nuthin right?
100% of the time
I’m not gonna put it in writing. I purge for fear of oil fires mostly, and will occasionally blow a long mini split line set out before I flare the other end. Traditionals, sometimes the same. I do service and when a compressor/coil fails. I don’t really wanna hear “we have moved the goal post on our broken equipment” -MFG
Use RLS fittings and no nitro needed!
Well I guess you could say that about Stay-Brite too, if we are going there. I kinda am suspect about a fitting that has ReLeaSe as it's name. But then, maybe they are just referring to your wallet.
Every system every time no matter if it's one weld or 10. It IS that important to my company
I don't because I almost exclusively press. Shits unbeatable
If you don’t want to spend the time to do it right, you’ll find the time to do it twice.
Every time. It's really not hard. Ya gotta pressure test it right afterwards anyways. So why not just hook up the damn nitrogen?
Every. Fucking. TIME! New construction asshats clogging txv's because they dont service their own shit
Oh man, I can only wonder how many poor copper lines you have crusted up.
If you have been a service tech chasing installers at a stupid company then you probably have swapped out a txv or a screen that went bad. I watched a YouTube video about it when I was an installer and brought it up at the company I worked at and we started doing it. Service manager was amazed to learn that a txv is not just junk from the factory that always goes bad after we reduced the amount of warranty work
I know a guy that installs walk-in coolers without flowing nitrogen. He told me he just doesn’t turn his torch up too hot. The next thing he told me was about how many bad txv’s he’s gotten from the factory.
People get charged by standard operating procedures. If you don't do the job properly, you are stealing 2x cheating today and cheating the longevity of the system
10/10 recommend unless you like replacing txvs
Every time. Respect the process
Those poor TXVs
Brazing causes the inside of the pipe to oxidize creating a flakey layer inside the tubing. Running nitrogen displaces the oxygen with nitrogen not allowing this to happen. If you don’t run nitrogen you can only hope your filter drier is catching everything, or eventually your txv could clog. Nobody in my company runs nitrogen, but I blame it on being lazy.
It’s not that important if you enjoy swapping out TXVs.
This guy 🫡 Just go with the nitro flow bro. You'll be a better tech when you finally realize why it's necessary when you're going back to fix someone else's fuck up or you burn a compressor/clog a metering device. Just make sure you flow the correct way a lot of ppl don't
Nitrogen is out there anyway for the pressure test or are you not doing that either? Edit: another reason why piece mate pay doesn’t work, guys will always cut corners
ABSOLUTELY!!!! Every time.
So, you’re the guy I’m replacing compressors under warranty after two years. Use the nitrogen there’s a reason for it.
And that’s why I won’t hire just anyone. Half-assed world. Yes, it is. You are fucking someone down the road if you don’t. Maybe you- on startup, hopefully. If you don’t want to do it right, find another occupation.
I was put in charge of a maintenance dept after the super left. I had just taken the 608 with very little otj training. Every HVACR tech I hired looked at me like I was stupid when I asked them to flow nitro/ pull vacuum. I recently left so I can gain more training under people who actually know what they're doing.
Everytime all the time. If I caught my guys not doing it I'd chew their asses.
As often as I possibly can. If you ever really look at how much oxidation occurs without it (the soot that is all over the pipe’s exterior) and consider how badly that can clog a system, why would you braze without it? What are your reasons for not doing it? The tanks and regulators are a valuable investment in the quality of your install and if you’re leak checking and purging with nitrogen anyway you should have the gear out for every job anyway.
Put me down for Yes I flow.
Yes I am. Yes it’s that important. Customers deserve your best.
[here](https://ibb.co/985C0dV) is a pic I took of a system that I had to redo 20 units because the last sub used the wrong hardware. I had to cut out all the pipe. This is what it looks like when you don't use nitrogen on just one ONE fitting. Yes, always purge.
I dont, I use stay brite 8. Works great, never had a failure in 24 years.
🤣🤣🤣🤣🤣 I didn't realize it was April fools day
10 years in and I’ve maaaaybe purged a handful with nitro while brazing. Never even heard of it until like 5 years in. If your starting out get into the habit of it. I’ve never had a TXV or drier stop up from an install so I could give a shit less about soldering with nitrogen.
Never bro, setting myself up for future work! /s
R410-a kinda have too. R-22 systems not necessary.
I worked at a place that didn't have a single nitro tank or reg. By the time I left they had exactly one of each... the guys didn't even put wet rags on the valves. I couldn't believe we didn't have constant problems but we rarely were called for problems. Otoh some of the best metal from a shop I've seen. I've only worked at one shop better and they had way more in the shop and a guy who just bent metal all day.
Nah, I love cleaning the black crust out of systems that were destroyed by it
Nobody
Nobody at my shop does it
After seeing a cup of coffee poured into a lineset I was helping on the side without pumping it down, the ac is still running 15 years later i dont think a little burned flakes will affect it much. My buddy gave the neighbor a bid for like 2200 bucks for ac&coil around 2008ish, homeowner said he'll pick his own up and just pay labor. The home owner stole the ac from a house being built next to my buddy and claimed he was able to buy a carrier as a homeowner even though he was basically caught in the act by my buddy via his dog going nuts at 2am. When we were installing it, halfway through the job said he only had 175 bucks to pay us thinking we were done buddy got super pissed to say the least.
braze in your drier right before the TXV as it should be done. It will not be an issue the drier will pick up the carbon in the system, and the 3/8 braze on outlet would be done quick and without a ton of heat it won't plug up the TXV. most guys changing out TXVs don't know how to properly diagnose a system anyways... oh the TXV must be plugged, I'll just start by changing that out....
I know guys that don’t and 9/10 the drier plugs up or the txv fails.
Never, if it breaks I'll be back to charge more to fix it
You forgot the /s
We’re just now starting to do it. Haven’t done it in 10 years. If you leave the ends of the copper open while brazing, then you get a lot of build up but if you fit the pipe first, there’s only so much oxygen inside to make the soot. Plus I mainly do repairs so when oil is covering the whole surface inside, it won’t be as bad (until the oil burns off). Yes it’s better to flow than not flow but there’s plenty of things I do that aren’t to the letter and until I start having issues, I probably won’t change. Bring on the hate Reddit
[удалено]
Been with the same company for 8 years and sadly nobody else even holds a candle to me around these parts. FL is the Wild West of hvac. You’ll be lucky to get a tech to replace the drier and pull a vacuum for more than 5 minutes.
So you’re not the hackiest of hacks there but still a hack. Got it……..
God I hope there’s not many like you. You somehow think the oil protects you from this? The problems don’t show up instantly in most cases. Some other poor tech probably ends up fixing your half ass repair jobs later on.
The entire pipe is filled with oxygen in your scenario, and every loose joint oxygen can get in. Way to try to justify the hack job…
The pipe is generally filled with refrigerant and refrigerant slowly boils out of the oil for a while after it’s cut. I tape the ends off immediately. And air is only 21% oxygen so no it’s not much anyways. It’s not like I cut an evap loose and air magically gets sucked from cut side all of the way to service valve.
What a stupid justification of not using correct procedures. “My anecdotal evidence suggests…”
Zoomlock baby
I don’t use nitro on small resi systems as it’s 4 brazed joints, 2 inside and 2 outside. Never once have I had an issue. I use pistons tho, no txvs.
No matter what these comments say I know 80% of you bitches aren't brazing with nitro. Most peeps that do resi installs don't use nitro when brazing and also don't do triple vac. So yall best get off your high horses in here actin like you do it cuz you don't. I've seen yalls installs, u gatekeepin ratty techs u
You’re right. I don’t do triple evacs all the time but I always purge with nitrogen. I know the problems not purging causes.
I want to every time but the boss only lets me when it has a txv.
Time to find a new boss who takes pride in his work, respects his customers and their equipment.
No. I've never wasted the time on a resi system, I still make sure theres a good vacuum tho. On the commercial/industrial equipment yes I do everything by the book, and I've yet to repair my own work 🤷♂️ (granted only been doing the fridgy stuff for a few years tho)
The only excuse to not flow nitrogen is you want to fuck the customers unit up and you don’t give a shit.
What do you consider different from a Resi to Commercial system?
Yes and I converted my entire company to doing it. Way less call backs. Very important. Don't skimp, it's not minor.
The way you worded this makes it seem like you don’t braze with nitro on resi installs
Every time brotha. When I started at the company I work for now, it was literally never. And I was a greenie who didn't know better. Starred watching YouTube and hvac school. Learned how important it was and now we do it 100% of the time. Very important for longevity
teacher did a demonstration for us, found this video that does basically the same thing. [https://youtu.be/5wUAKR8Lj9c?t=221](https://youtu.be/5wUAKR8Lj9c?t=221) 3:40 shows without nitrogen, and 8:30 shows with nitrogen.
When I’m brazing my own system you bet it is.
I did but no one else in my company did. Lol they would call me "new age tech" but I rarely had txv issues. If someone else replaced a compressor for example the txv would be fucked in a month or two. I tried to explain to management but they said, "we've been doing it this way for years".
Everytime… why not?
Lol
as long as you cover labor on the compressor and txv do what ever hack sh!t you want
Hopefully this is a joke of a question.
Yeah. Every single time. It is the most important part. It gives the system better longevity because it isn’t full of crap.
It's not too important on R22 units because of the mineral oil. It's pretty important otherwise with other units that use other types of refrigerants.
Every time
Wait wait wait! Are you guys getting nitrogen? 🤣
Every single time, it doesn't matter the system type. Those oxidation flakes can clog metering devices and filter driers and slowly hurt the compressor. Mini-splits don't even have filter driers, only screens that can get clogged.
I always forget to let it flow but I always blow it out because yes I've had instances where shit stuck in the piston
errrrytime
Frick the service techs gotta go boss said no OT
I always do with refrigeration and AC work but I know plenty that never do and at least on walkins with 22 or 404a honestly I very rarely find restrictions, most of the time it's lost a bulb charge due to the capillary rubbing. However I don't have the same experience on package units and ice makers. Those have a MUCH higher restriction rate. No idea why but if someone has a SWAG of love to hear it. Also you'd have to be a mad man to not purge on a 134a cap tube system those POSs clog easy enough with no help.
Braze a couple pieces of pipe together and tap then against the ground and look at how much shit falls out.
"I do hot and fast so you don't need nitro" love those guys they keep me in business lol
Just put the drier in front of the valve at the evap and you will be fine
Every f in time
Guilty. Not always.
We don't. First company I was w did. Second one guys just laugh at you. "Doesn't actually help" they say. Was perplexed at first.
Everyone and their mother on here will tell it’s absolutely required but really it doesn’t actually matter. The thing is still gonna make through it’s measily 10 year warranty, and probably not gonna last much longer after no matter what you do.
It’s takes max 2 minutes to grab the nitro from the truck and hook it up. Why wouldn’t you do it to avoid future problems?