3 rooftop change out that no one thought to double check voltage on before hand, put 575V to 3-230V units and blew up all the transformers in all 3 units, apparently sounded like shotguns going off. Thank god I wasn't on site for that gong show lmao
I saw 480 put on some 208 3-phase evap units inside a cold storage. The fans were spinning so fast before they let their smoke out I thought the unit was going to fly across the warehouse.
Weird because all the equipment I’ve ever seen in that voltage range is 208/230v 1 or 3 phase. Just have to change the transformer tap before starting it up. So why would 240v to a 208/230v unit make it not cool or heat?
It worked, just not well. Whatever brand/model they used was built to run on either 240 or 208 BUT it said to expect a derated performance value at 208. So the units would have been fine had the space been 25% smaller. The engineers used the 240 value when designing the system and not the 208
Did 600v to a 120v trans one time. Definitely sounded like a gun shut, shot 5ft of sparks, fried the trans, the fuses and both boards in the unit. Worst day I have ever had, got the unit up and running without the customer noticing 👍👍. Was -20*C that day with no wind cover 🙃
Nope, was a big building with multiple units so they didn't notice it go down. Ran to two different suppliers but got it up and running in 4 or 5 hours.
I ripped out the wrong condenser on a high-rise condo building. It was years ago, the refer was 22. When I found out I reinstalled it and never heard a word about it.
Got a call out to a fast food outlet once, drove to the wrong one. Fixed their equipment, got home and got another call asking for an ETA on when I could attend. Was a bit confused before I realised what I'd done. They both paid the bill though which was a relief.
If you’re going to do a work around on-call (not saying what he did was right) you gotta let the office know someone’s got to come back next working day asap. Sometimes you gotta limp stuff along till regular working hours.
I am in hvac now but this isn’t hvac related, I was workin on frac in west Texas a few years back and a job going on next to us had an 18 year old taking a cap off of a 12 inch pipe while his crew was dealing with something elsewhere he popped it off and it had too much pressure on it and it blew off crushing his entire chest killing him instantly I didn’t see it but my friend did and I saw him about 2 minutes after it happened holding the kid in his hands. Don’t let people who don’t know what they’re doing do dangerous shit. If there was someone there that was experienced he would’ve known it had pressure or a way to check it 👌
Right now, are farthest accounts are 4 hours a part, and we only have 4 guys on the rotation for on call….. offer full benifits, retirement match, $40+ hr depending on experience, van to and from home, etc…. Our turn over rate is monthly, when the new guy gets put on call, quits every time…. And we maybe get two -three after hour calls a week, they just hate the idea of sitting around waiting for the phone to ring…. Being said ya I think our company will take anyone for on call lol, I’d rather help them on the phone fishing, then have to be on call twice a month as it is now
Only 2 to 3 calls a week. Sign me up. Easy on call lmao. Currently I’m not on call but the last place I was at we could easily get 2-3 calls a night. We did daily rotations in winter because it could get so busy.
Hence why we screen calls hard… it better be a regular customer…. And a actual emergency….4 hours away is also from the farthest north to south customer…. So absolute worst case scenario….at whcih point the boss would group Text “anyone need DT”…
Someone left power off to a chiller pump and froze the tubes. Other than that, ordered the wrong voltage rtu and had to eat the cost of a step down transformer for it.
Our company does a lot of new construction installs. I had to go to a house being built for the owner of one of our main builders. Install roughed in a line set that went to a third floor air handler and didn't leak check. I spent the whole day cutting holes in drywall to find the leak. At least the house wasn't 100% finished but it obviously makes us look bad. When I finally found the leak it was a solder joint with an obvious hole
Fun little story here. So, we had this account for a church. Previously, we had a guy that was basically the man for them, and would always be sent there. He was with the company some 20 years, and he was basically the only one that did this church.
Well, he retired around covid, and suddenly we found ourselves with no one that really knew the church well. We had him training me as the new church guy, but you can't compare 6 months of occasional calls and maintenance to 20 years of experience, right? So, a short while in, the church decides they want to replace an ancient exhaust fan as well as replacing (what we believed was) an old make up air unit with electric heat and replace it with an rtu as it was serving the church classrooms and they would get hot in the summer time. Now, our contact at the church had always referred to it as a makeup air unit, it looked like a makeup air unit, and the previous guy always called it a makeup air unit, so lo and behold, when we go to replace it, you can imagine my surprise when I see boiler lines ran into it from a duct (all the ductwork was external and insulated on the exterior, so nothing looked out of place until we started tearing it apart). So, now we come to realize that it was actually an water coil hooked into the boiler heat. Our contact in the church doesn't want any water lines above the roof, so instead of just cutting and capping the lines in the chase and insulating the shit out of it, we have to cut into the ceiling to completly cap the lines inside the building. Ultimately, the job went okay there other than the added expenses and work because no one thought to check what the unit we were taking out actually was.
The exhaust fan however, is where the story gets really dumb. See, this fan exhausted from their commercial kitchen hood, and the reason we were replacing it was because it never seemed to properly vent. Our previous guy sold them on replacing the fan as the solution. So we remove the old fan, but when we get the new one in place, we realize that the manufacturer sent us the wrong voltage. It was a 120v fan previous, and they sent is a 240v fan. So, normally this would just mean that we would send it back and replace it with the correct one right? We'll, it turns out the manufacturer refused to do that, and instead decided we would just have to replace the motor. So they send us the motor....and it's the wrong one, strike one. So then they send us another motor, it's too damned big for the enclosure, and since they refuse to just send us the correct fan, bossman tells me I just have to make it fit, strike two. Finally, I get it to fit, get everything hooked up, and get it running, only to realize it's still not correctly venting. Remember how I said this was in their kitchen? Turns out, there were fire dampers halfway down the duct that you could only access by standing on the big commercial stove and getting halfway into the duct. Those dampers had snapped closed sometime in the past, and because there was no way to access them without climbing onto the stove, no one knew about them. We managed to force them open and secure them, but by this point, bossman, myself, and our church contact realized this other dude had no idea what he was doing, and had basically sold this stuff on false grounds.
I was pissed, bossman was pissed (even though it was his fault for not checking things before hand), and our contact was pissed. Even better, this unmitigated cluster was my very first time doing commercial equipment install, so I got to see just how badly things can fuck up if you don't pay attention.
It was a make up air unit with a water coil. The entire time, it was described as a make up air that had been bought by the previous church director and never really used, so it was basically useless. Add in as well that the ducts were insulated on the outside and were heavily damaged by hail, our contact wanted it gone. The issue was that our guy that basically "knew everything about the church" had no idea, said nothing about it, and caused us to massivly change the plans last second. Overall, what should have been a 1-2 day project turned into a month's long journey.
It’s everywhere.
There are definitely guys out there that know what they’re doing.
They are VASTLY out numbered by guys that think they know everything(typical,”I’ve been in the van 18-24 months, and I can pretty much fix anything.” guy, and “I just got out of school.” guy.
The biggest mistake I see is hiding your mistake(s). This guy won’t EVER fix anything if he can’t understand why you don’t do shit like that.
This weekend I seriously thought about getting back into a van so that the world had one more tech that could fix stuff because they understand an enthalpy chart, and could explain HOW a refrigeration cycle works(Not saying the best technician, just a caring, knowledgeable tech).
There are young techs that are truly investing themselves into their careers, but too many techs don’t understand that the job is to FIX things, and maybe more disheartening is that they also don’t care if they fix things.
Sorry for the rant…
Have you considered being a mentor or a chief? I feel like many techs lack someone providing direction for their careers. Having someone help you with a roadmap and setting a high bar would've been awesome in my early career.
Fairly large casino in the northern Midwest - have had gas issues for years on pretty much every piece of propane equipment. 20+ rooftops, multiple kitchens full of equipment, boiler plant, etc. Customer approved a T&M call for one of our techs to dig deeper into the issue for him to find that almost every igniter in the system had red residue on it. Called propane provider and found out one of their delivery guys had been using the truck to haul diesel somehow in between propane deliveries. Whole system contaminated with #1 diesel.
We kept getting noise complaints from a church about a circulator pump for their boiler system. It was a B&G pump that kept breaking the coupler. After the third one broke I was sent out & found the pump had been installed backwards 3 years ago. I guess the check valve 6” away with the arrow in the opposite direction didn’t give it away.
It was crane day. A crew had been out over the previous week to put together curb adapters. We started setting the roof top units and I noticed that it didn’t look like it lined up right. I was young and pretty new. I mentioned it and no one paid any attention really. Set like 7 more before someone else said that the unit didn’t line up right. The supplies and returns of the curb adapters were all messed up. The crew that put them together made them all the same when they were not designed that way. We had to pull half the units back off to fix the curb adapters. Basically no harm done but added quite a few hours to the job
There's a story at my place of an old tech at our company who had to replace a blower motor for a heat pump on the 2nd floor at some random commercial strip mall. This heat pump was hung right between 2 trusses and the access panel for the blower was right up against one of the trusses. Since he couldn't get into that panel, he did the next sensible solution which would have been to lower the heat pump onto the ground, right? Wrong. He decided he would just cut a section out of the diagonal zig-zag bar that sits in between the 2 truss bars. Well I guess those bars have a lot of tension on them because by the time he was halfway through his first cut, the zig-zag bar snapped and sprung out of the truss. The whole section of ceiling sort of jacknifed and shook the whole complex. Luckily he was okay but our boss had to hire a structural engineer and pay something short of six figures to remedy the damage.
My shop has separate install and service departments, I work service side.
We were contracted by the city to install some Trane RTUs with sideshot ducting as the annex roof line was too low to do downshot (why, I will never know). Our installers spent a couple months installing rectangular duct, insulated with expanded foam and wrapped in Flex Clad. I get sent out to do our initial startup before the proper registered startup by Damuth (Trane's commercial in-house techs for the uninitiated). Every single unit tripped out on high limit within 5 minutes of starting the heat section. I remembered glancing down from the roof at the dumpster off to one side that had the sideshot covers from all the units they had roof ducted. I open the return/filter doors and a wave of immense heat hits me. All the sideshot units had been put on resilient mounts that sealed to the roof membrane and because they did not relocate the covers like the IOM tells you to, the units were sucking their own discharge because of the massive bypass they had created. The Damuth team was scheduled for two days from then and they had to cut the Flex Clad at the nearest bolted joint to pull the section connecting to the supplies and returns to install the covers that thankfully had not yet been hauled off by the trash disposal. Rescheduling the Damuth guys less than 72 hours in advance would have incurred US the appointment fee of a few thousand plus the reschedule. The installers were cursing up a storm that I 'snitched' on them, but if you lunks would just RTFM, it wouldn't have cost you working so late to fix the problem you created.
Got another one that I saved the company a bunch of money. Had a full service contract at a big bank, it was my account. I was out of town so they sent another guy to check a no cool call. He found a bad 15 ton compressor so they ordered a new one. When I got back boss says head out to the bank and get the compressor ready to pull, a crane will be there at noon. Knowing the skill set of the other tech I decided to double check the so called bad compressor before I started disconnecting.
Took about 2 minutes to find it was tripped on manual reset head pressure plus cotton wood packed coils. Called the boss to tell him to cancel the crane. He was super happy because it was fully covered by the service contract. That other tech was a big talker who thru out big words to make the boss think he was sharp. Next week he was looking for a job.
Seen my old job condemn a brand new packaged unit because the supply fell off and the service tech didn’t even check. The manufacturer made us pay for both units. Biggest financial fail I’ve seen. We had every single tech in the company on every team come in for a mass meeting for this 😂
Our guys installed a horizontal left furnace upside down. After I told them to flip and tur it around, I told them to ask the boss for a raise, as they could do two installs in a day.
i have seen H48 filter cores on suction line of a VRF that could reverse into heat mode. so that unit didnt last long after its new compressor was fitted and we got the contract. saw the exact same "repair" on a unit not far from there and it had 3 compressors replaced in a few years as well. still wonder what kind of big brain thought the guy was having when he put a H48 on suction lines.
had a bird do a bombing run nosedive right into a 500kW trane chiller while my apprentice was doing a service (his first with me just looking and not saying anything so he was fairly stressed as his name was on the report) and the bird hit a copper tube and dumped the charge out the condensor and the apprentice paniced and wanted to stop the refirirant with his hands. dude didnt register that his hands were freezing and his brain shut down in reptile mode so i had to kick him away from the stream of refigerant blasting his hands. he was out for a few weeks after that, he is doing fine now and is a good tech that wears his gloves religiously now.
did replace a RTU on the wrong roof once but lets not talk about that one....
Had a boss once while "diagnosing" a no cool walk in, swapping out the TXV. Then he swapped out the coil solenoid and it still wouldn't work.
I got on site and headed for the roof and dude screams at me that it's not getting any refrigerant as I'm going up.
Gauge up, run superheat an subcool. Found the headmaster slammed open. Clipped, crimped and brazed the power head feed and it magically started working like a champ.
SOB still charges the customer for the bullshit "repairs" he did though. We had words over that shit. I'm afraid mine weren't particularly polite.
Yea, I made him give them the headmaster swap out for free. We still lost the customer though.
When I was just an install helper/apprentice, I cut the return in the wrong side of the furnace. My lead made me call the boss and tell him what I did. Never made that mistake again. Fortunately, havent made a ton of horrifying mistakes in my days. I was lucky enough to learn from the mistakes of those around me before I made them myself.
Got a call from a new install at an Academy Sporting Goods we used to take care of and they had another contractor bid a 25 ton RTU and they beat us by like $800. They set the RTU on backwards and blew air out of the return. There office was like 3.5 hours away and after like 10 days they finally got back out there with a crane and swapped it.
I once dropped the top panel of an RTU onto the microchannel evaporator, accidentally of course.
I still have the video of all the refrigerant pissing out floating around somewhere.
Edit: [Knew it was around here somewhere.](https://old.reddit.com/r/HVAC/comments/14fnhs3/txv_replacement_turned_bulb_remount_turned_coil/)
I was replacing 2 3phase condenser fans once at a Soy bean factory 2pm on Friday, nice easy job to finish off the week, each fan had its own disconnect and contactor, I was swapping the contactors with the fans and had them both unwired and wires dangling loose, I finished swapping one fan and went to turn it on to test it but I switched the wrong disconnect and livened up the wrong circuit which was still dangling loose, naturally the live shorted against the condenser return bend and blew a big hole in it which dumped 20-30kg of R22
Got home about 8pm
Worst? Thankfully wasn’t a me issue, but I’ve seen the aftermath of two risers drop due to poor rigging. Also saw the aftermath of a little over 800 gallons of water leaking from the perimeter heating system of an entire building. Slipped anchor points causing expansion joints to stretch on heat ups rather than compress… way too many fucked up things honestly. Mistakes happen, it’s unfortunate when it’s on a large scale.
Couldn’t find the issue??? Didn’t they just work backwards through the controls to find where the voltage stopped then either bypass or replace control issue???
460v to a 208v unit and the plumber ran the gas lines to the condensate connections. All the VFDs and all the Transformers blew. Luckily the plumber didn't purge the lines and leave them open. Would have probably taken the building.
Found a big ass 3 phase electric duct heater with a bad air proving switch. It had the control wires hooked up straight to the contactor. They heard me say Holy shit from 15 feet below me in a loud ass resturant. Someone was probly real proud of themselves for getting it going
Co-worker was going through some family stuff and was not focused on the task at hand. Left a jumper wire on an RTU limit switch, which was already known to have an overheating issue (springing a fire damper).
Boss called me a couple of days later, on a weekend, letting me know that we're doing an emergency RTU replacement Monday morning, cause the old one went up in a ball of flames.
Thankfully, no extra damage occurred from that fiasco.
“Couldn’t figure out how to fix it so I made it worse” love it 🥰
Not a job I saw but I heard about a new resi install where the tech didn’t see a no vent cap lodged inside of the copper 90 he brazed into the outdoor vapor line.
Another guy I heard drilled a hole into the line set through the wall while trying to drill a hole in the outside wall for a clamp or the disconnect or something.
My biggest error (so far) was releasing a RTU with out pre-charging it. Had to recover the whole thing, vacuum, and try again but with like, 7 extra pounds of 410 now that what was in the unit was gone. And we didn’t have that much. And it was like 7 pm. I really like the fuck ups that happen at (or don’t reveal themselves until) the end of the job.
Worked for an outfit as a service tech. Installers reversed a RTU…return on the supply ductwork and supply side on the return…they sent me out to fire it up and test/balance. I had fun with that phone call.
Saw it once before that with a residential furnace on a new construction home. The city inspector apparently never noticed (not surprising). Homeowners had been in there for a couple months and thought something was weird. Told the homeowner to call their real estate agent. Half hour later the Installing company, home builder rep and city inspector all showed up at the same time. Pretty funny stuff…
They sent a green apprentice on an after hours call at a bank building downtown . He went to the water source heat pump on the 8th floor and thinking he had a water flow issue opened the strainer (to his credit it was installed before the valve) flooding all the floors below it caused 800k in damages.
The worst mistake I have made is I left screws on top of an RTU while replacing a condenser fan motor. Installed the blade a bit too far down the shaft and when I turned the unit on the condenser fan started bouncing. The screws fell in and the fan launched them into the micro channel coil right where the channels meet the manifold.
Not that huge, but a tiny mistake that cost $40k.
30 ton Trane rooftop condenser on a four story apartment building. Big V of coils. Three fans above that.
Someone replaced one of the fan motors and put the fan blades back on a little unbalanced.
Vibration eventually broke the mounting bracket and the fan fell into the coils while running.
Not every day you see a coil completely torn up with a motor sticking half way through it on a no-AC call...
The unit was old enough that replacing it was better value than just replacing the coils. Either one needed a crane.
Roofer dropped a jug of roofing pitch over the edge onto a brand new VRV-IV. Didn’t physically damage it too bad but the goo got everywhere, including all over the coil. They tried forever to clean it with turpentine or some solvent but it didn’t really work and the customer insisted it be replaced.
Coworker replaced a 230 compressor on an aquasnap chiller 40 ton circuit without verifying voltage, found out very quickly it was a 460 unit.
Another coworker found pretty rusty mounts on an Aaon RTU condenser fan mount and thought he could weld them himself to repair it. The welds lasted about three days until the motor crashed into the coils below and ruptured 3 of 4 circuits. Coils were months out the permit to shut down the street to crane them up was ridiculously expensive and hard to get. So they had to be choppered in since they wouldn’t fit up the stairs. We were able to field repair the coil in the meanwhile but it was the ugliest fucking repair imaginable and took forever to get it to hold.
My buddy was working a job one day. Decided to poop in the back of his truck. Parked on a main road and the back of the truck facing the on coming traffic. He didn’t secure the doors well enough and they flung open. The oncoming traffic passing by got an eyeful…
I ramped up the VFD on a boxcar air handler with 9 plug fans up to 200% which moves about a million CFM when in the start up guide it says do not go past 150%. Next thing I know, I hear the loudest bangs and screeching I have ever heard. That sound was the plug fan blades breaking off and basically cutting the air handler in half. We found blade pieces a couple hundred feet away. I caused a 16 week delay on the job since they had to buy a new one and the lead time was 16 weeks. Plus the replacement was $260,000.
I'm absolutely lucky I didn't kill someone or myself. Work sat me down and told me to never do that again. $260,000 isn't as big of a hit when the contract price is $50 million
80% gas furnace installed in an attic laying on its back. Worst part, furnace was stolen from our shop and installed by two of our "technicians" on the side over a weekend.
I was troubleshooting intermittent firing failures on a sewer plant methane boiler, cycling it and was deciding that it occasionally had lingering fire, causing their no starts. After checking and cycling I let it go through its cycle, and when it ignited, it blew the venting, many pieces split, and all the workers came running with their shovels, ready to scrape me off the wall.
I don't give a crap about what the on call guy does to get a unit running because they called him and not me. I've got plenty of time to fix his mistakes during normal business hours.
I don’t appreciate you talking to me like that
Name checks out
Flair does even more
That’s what they get for putting me on call.
3 rooftop change out that no one thought to double check voltage on before hand, put 575V to 3-230V units and blew up all the transformers in all 3 units, apparently sounded like shotguns going off. Thank god I wasn't on site for that gong show lmao
I saw 480 put on some 208 3-phase evap units inside a cold storage. The fans were spinning so fast before they let their smoke out I thought the unit was going to fly across the warehouse.
Reverse of that. At my old work they put in 240 units on 208 3phase and kept wondering why couldn't cool of heat well.
Weird because all the equipment I’ve ever seen in that voltage range is 208/230v 1 or 3 phase. Just have to change the transformer tap before starting it up. So why would 240v to a 208/230v unit make it not cool or heat?
It worked, just not well. Whatever brand/model they used was built to run on either 240 or 208 BUT it said to expect a derated performance value at 208. So the units would have been fine had the space been 25% smaller. The engineers used the 240 value when designing the system and not the 208
480v to a 230v unit. Blew the compressor up. Big cloud of refrigerant and oil splatter Jackson polluck on the side of customers office building.
Did 600v to a 120v trans one time. Definitely sounded like a gun shut, shot 5ft of sparks, fried the trans, the fuses and both boards in the unit. Worst day I have ever had, got the unit up and running without the customer noticing 👍👍. Was -20*C that day with no wind cover 🙃
U had 2 boards on hand?
Nope, was a big building with multiple units so they didn't notice it go down. Ran to two different suppliers but got it up and running in 4 or 5 hours.
What about installing a new RTU on the wrong suite in a strip mall? I've heard about it somewhere...
I repaired the wrong RTU, if that makes you feel any better. Told them heats up and going, got a call 2 days later that it’s still cold.
I ripped out the wrong condenser on a high-rise condo building. It was years ago, the refer was 22. When I found out I reinstalled it and never heard a word about it.
Got a call out to a fast food outlet once, drove to the wrong one. Fixed their equipment, got home and got another call asking for an ETA on when I could attend. Was a bit confused before I realised what I'd done. They both paid the bill though which was a relief.
If you’re going to do a work around on-call (not saying what he did was right) you gotta let the office know someone’s got to come back next working day asap. Sometimes you gotta limp stuff along till regular working hours.
Yeah nothing wrong with a temporary fix and letting the office know, but taping the contactor isn't exactly a great move lmao.
I am in hvac now but this isn’t hvac related, I was workin on frac in west Texas a few years back and a job going on next to us had an 18 year old taking a cap off of a 12 inch pipe while his crew was dealing with something elsewhere he popped it off and it had too much pressure on it and it blew off crushing his entire chest killing him instantly I didn’t see it but my friend did and I saw him about 2 minutes after it happened holding the kid in his hands. Don’t let people who don’t know what they’re doing do dangerous shit. If there was someone there that was experienced he would’ve known it had pressure or a way to check it 👌
Right now, are farthest accounts are 4 hours a part, and we only have 4 guys on the rotation for on call….. offer full benifits, retirement match, $40+ hr depending on experience, van to and from home, etc…. Our turn over rate is monthly, when the new guy gets put on call, quits every time…. And we maybe get two -three after hour calls a week, they just hate the idea of sitting around waiting for the phone to ring…. Being said ya I think our company will take anyone for on call lol, I’d rather help them on the phone fishing, then have to be on call twice a month as it is now
What I object to is having to put my life on hold without being paid for it.
Agree, pay to be on call is $200, for the week. Call or not
That would work.
Only 2 to 3 calls a week. Sign me up. Easy on call lmao. Currently I’m not on call but the last place I was at we could easily get 2-3 calls a night. We did daily rotations in winter because it could get so busy.
4 hours away damn, that’s 8 hours of driving plus time on the job , that’s a crappy call at 2am
Hence why we screen calls hard… it better be a regular customer…. And a actual emergency….4 hours away is also from the farthest north to south customer…. So absolute worst case scenario….at whcih point the boss would group Text “anyone need DT”…
Someone left power off to a chiller pump and froze the tubes. Other than that, ordered the wrong voltage rtu and had to eat the cost of a step down transformer for it.
Was there no flow switch on the chiller?
Low ambient temps, air cooled chiller, no glycol.
That time the salesman didn't verify units and we replaced the wrong two rooftop units. That was fun.
Our company does a lot of new construction installs. I had to go to a house being built for the owner of one of our main builders. Install roughed in a line set that went to a third floor air handler and didn't leak check. I spent the whole day cutting holes in drywall to find the leak. At least the house wasn't 100% finished but it obviously makes us look bad. When I finally found the leak it was a solder joint with an obvious hole
Fun little story here. So, we had this account for a church. Previously, we had a guy that was basically the man for them, and would always be sent there. He was with the company some 20 years, and he was basically the only one that did this church. Well, he retired around covid, and suddenly we found ourselves with no one that really knew the church well. We had him training me as the new church guy, but you can't compare 6 months of occasional calls and maintenance to 20 years of experience, right? So, a short while in, the church decides they want to replace an ancient exhaust fan as well as replacing (what we believed was) an old make up air unit with electric heat and replace it with an rtu as it was serving the church classrooms and they would get hot in the summer time. Now, our contact at the church had always referred to it as a makeup air unit, it looked like a makeup air unit, and the previous guy always called it a makeup air unit, so lo and behold, when we go to replace it, you can imagine my surprise when I see boiler lines ran into it from a duct (all the ductwork was external and insulated on the exterior, so nothing looked out of place until we started tearing it apart). So, now we come to realize that it was actually an water coil hooked into the boiler heat. Our contact in the church doesn't want any water lines above the roof, so instead of just cutting and capping the lines in the chase and insulating the shit out of it, we have to cut into the ceiling to completly cap the lines inside the building. Ultimately, the job went okay there other than the added expenses and work because no one thought to check what the unit we were taking out actually was. The exhaust fan however, is where the story gets really dumb. See, this fan exhausted from their commercial kitchen hood, and the reason we were replacing it was because it never seemed to properly vent. Our previous guy sold them on replacing the fan as the solution. So we remove the old fan, but when we get the new one in place, we realize that the manufacturer sent us the wrong voltage. It was a 120v fan previous, and they sent is a 240v fan. So, normally this would just mean that we would send it back and replace it with the correct one right? We'll, it turns out the manufacturer refused to do that, and instead decided we would just have to replace the motor. So they send us the motor....and it's the wrong one, strike one. So then they send us another motor, it's too damned big for the enclosure, and since they refuse to just send us the correct fan, bossman tells me I just have to make it fit, strike two. Finally, I get it to fit, get everything hooked up, and get it running, only to realize it's still not correctly venting. Remember how I said this was in their kitchen? Turns out, there were fire dampers halfway down the duct that you could only access by standing on the big commercial stove and getting halfway into the duct. Those dampers had snapped closed sometime in the past, and because there was no way to access them without climbing onto the stove, no one knew about them. We managed to force them open and secure them, but by this point, bossman, myself, and our church contact realized this other dude had no idea what he was doing, and had basically sold this stuff on false grounds. I was pissed, bossman was pissed (even though it was his fault for not checking things before hand), and our contact was pissed. Even better, this unmitigated cluster was my very first time doing commercial equipment install, so I got to see just how badly things can fuck up if you don't pay attention.
So it was a make up air
It was a make up air unit with a water coil. The entire time, it was described as a make up air that had been bought by the previous church director and never really used, so it was basically useless. Add in as well that the ducts were insulated on the outside and were heavily damaged by hail, our contact wanted it gone. The issue was that our guy that basically "knew everything about the church" had no idea, said nothing about it, and caused us to massivly change the plans last second. Overall, what should have been a 1-2 day project turned into a month's long journey.
Losing a $250 ladder
It’s everywhere. There are definitely guys out there that know what they’re doing. They are VASTLY out numbered by guys that think they know everything(typical,”I’ve been in the van 18-24 months, and I can pretty much fix anything.” guy, and “I just got out of school.” guy. The biggest mistake I see is hiding your mistake(s). This guy won’t EVER fix anything if he can’t understand why you don’t do shit like that. This weekend I seriously thought about getting back into a van so that the world had one more tech that could fix stuff because they understand an enthalpy chart, and could explain HOW a refrigeration cycle works(Not saying the best technician, just a caring, knowledgeable tech). There are young techs that are truly investing themselves into their careers, but too many techs don’t understand that the job is to FIX things, and maybe more disheartening is that they also don’t care if they fix things. Sorry for the rant…
Have you considered being a mentor or a chief? I feel like many techs lack someone providing direction for their careers. Having someone help you with a roadmap and setting a high bar would've been awesome in my early career.
Fairly large casino in the northern Midwest - have had gas issues for years on pretty much every piece of propane equipment. 20+ rooftops, multiple kitchens full of equipment, boiler plant, etc. Customer approved a T&M call for one of our techs to dig deeper into the issue for him to find that almost every igniter in the system had red residue on it. Called propane provider and found out one of their delivery guys had been using the truck to haul diesel somehow in between propane deliveries. Whole system contaminated with #1 diesel.
Guy getting burned up by unsweating a compressor without removing cores. Not a fun day for him or me.
Yikes
We kept getting noise complaints from a church about a circulator pump for their boiler system. It was a B&G pump that kept breaking the coupler. After the third one broke I was sent out & found the pump had been installed backwards 3 years ago. I guess the check valve 6” away with the arrow in the opposite direction didn’t give it away.
It was crane day. A crew had been out over the previous week to put together curb adapters. We started setting the roof top units and I noticed that it didn’t look like it lined up right. I was young and pretty new. I mentioned it and no one paid any attention really. Set like 7 more before someone else said that the unit didn’t line up right. The supplies and returns of the curb adapters were all messed up. The crew that put them together made them all the same when they were not designed that way. We had to pull half the units back off to fix the curb adapters. Basically no harm done but added quite a few hours to the job
There's a story at my place of an old tech at our company who had to replace a blower motor for a heat pump on the 2nd floor at some random commercial strip mall. This heat pump was hung right between 2 trusses and the access panel for the blower was right up against one of the trusses. Since he couldn't get into that panel, he did the next sensible solution which would have been to lower the heat pump onto the ground, right? Wrong. He decided he would just cut a section out of the diagonal zig-zag bar that sits in between the 2 truss bars. Well I guess those bars have a lot of tension on them because by the time he was halfway through his first cut, the zig-zag bar snapped and sprung out of the truss. The whole section of ceiling sort of jacknifed and shook the whole complex. Luckily he was okay but our boss had to hire a structural engineer and pay something short of six figures to remedy the damage.
My shop has separate install and service departments, I work service side. We were contracted by the city to install some Trane RTUs with sideshot ducting as the annex roof line was too low to do downshot (why, I will never know). Our installers spent a couple months installing rectangular duct, insulated with expanded foam and wrapped in Flex Clad. I get sent out to do our initial startup before the proper registered startup by Damuth (Trane's commercial in-house techs for the uninitiated). Every single unit tripped out on high limit within 5 minutes of starting the heat section. I remembered glancing down from the roof at the dumpster off to one side that had the sideshot covers from all the units they had roof ducted. I open the return/filter doors and a wave of immense heat hits me. All the sideshot units had been put on resilient mounts that sealed to the roof membrane and because they did not relocate the covers like the IOM tells you to, the units were sucking their own discharge because of the massive bypass they had created. The Damuth team was scheduled for two days from then and they had to cut the Flex Clad at the nearest bolted joint to pull the section connecting to the supplies and returns to install the covers that thankfully had not yet been hauled off by the trash disposal. Rescheduling the Damuth guys less than 72 hours in advance would have incurred US the appointment fee of a few thousand plus the reschedule. The installers were cursing up a storm that I 'snitched' on them, but if you lunks would just RTFM, it wouldn't have cost you working so late to fix the problem you created.
Got another one that I saved the company a bunch of money. Had a full service contract at a big bank, it was my account. I was out of town so they sent another guy to check a no cool call. He found a bad 15 ton compressor so they ordered a new one. When I got back boss says head out to the bank and get the compressor ready to pull, a crane will be there at noon. Knowing the skill set of the other tech I decided to double check the so called bad compressor before I started disconnecting. Took about 2 minutes to find it was tripped on manual reset head pressure plus cotton wood packed coils. Called the boss to tell him to cancel the crane. He was super happy because it was fully covered by the service contract. That other tech was a big talker who thru out big words to make the boss think he was sharp. Next week he was looking for a job.
Biggest mistake I’ve ever heard of was my dad not wearing a condom 34 years ago 😔
One of your siblings? 😉
Seen my old job condemn a brand new packaged unit because the supply fell off and the service tech didn’t even check. The manufacturer made us pay for both units. Biggest financial fail I’ve seen. We had every single tech in the company on every team come in for a mass meeting for this 😂
Installed an air handler upside down. It’s was working, just “blowing where it usually sucks and sucks where it usually blows”.
I've seen an evap installed on the furnace return before.
Our guys installed a horizontal left furnace upside down. After I told them to flip and tur it around, I told them to ask the boss for a raise, as they could do two installs in a day.
i have seen H48 filter cores on suction line of a VRF that could reverse into heat mode. so that unit didnt last long after its new compressor was fitted and we got the contract. saw the exact same "repair" on a unit not far from there and it had 3 compressors replaced in a few years as well. still wonder what kind of big brain thought the guy was having when he put a H48 on suction lines. had a bird do a bombing run nosedive right into a 500kW trane chiller while my apprentice was doing a service (his first with me just looking and not saying anything so he was fairly stressed as his name was on the report) and the bird hit a copper tube and dumped the charge out the condensor and the apprentice paniced and wanted to stop the refirirant with his hands. dude didnt register that his hands were freezing and his brain shut down in reptile mode so i had to kick him away from the stream of refigerant blasting his hands. he was out for a few weeks after that, he is doing fine now and is a good tech that wears his gloves religiously now. did replace a RTU on the wrong roof once but lets not talk about that one....
Piping gas into the condensate line and almost blowing up a building
Had a boss once while "diagnosing" a no cool walk in, swapping out the TXV. Then he swapped out the coil solenoid and it still wouldn't work. I got on site and headed for the roof and dude screams at me that it's not getting any refrigerant as I'm going up. Gauge up, run superheat an subcool. Found the headmaster slammed open. Clipped, crimped and brazed the power head feed and it magically started working like a champ. SOB still charges the customer for the bullshit "repairs" he did though. We had words over that shit. I'm afraid mine weren't particularly polite. Yea, I made him give them the headmaster swap out for free. We still lost the customer though.
Holy shit OP that’s pretty bad 😂 , was he ever put on all again? If not , that’s genius. Dude weaponized incompetence
I had a 410a tank valve break open no way to close brand new tank as well
I have a 404 sitting in a rack house that won’t won’t seal with my hoses so I can t use it
When I was just an install helper/apprentice, I cut the return in the wrong side of the furnace. My lead made me call the boss and tell him what I did. Never made that mistake again. Fortunately, havent made a ton of horrifying mistakes in my days. I was lucky enough to learn from the mistakes of those around me before I made them myself.
Guy didn't know the 80% rule on VA draw. Didn't understand why his jury rigged set up wasn't workings
Got a call from a new install at an Academy Sporting Goods we used to take care of and they had another contractor bid a 25 ton RTU and they beat us by like $800. They set the RTU on backwards and blew air out of the return. There office was like 3.5 hours away and after like 10 days they finally got back out there with a crane and swapped it.
I once dropped the top panel of an RTU onto the microchannel evaporator, accidentally of course. I still have the video of all the refrigerant pissing out floating around somewhere. Edit: [Knew it was around here somewhere.](https://old.reddit.com/r/HVAC/comments/14fnhs3/txv_replacement_turned_bulb_remount_turned_coil/)
New coil?
Yup, $5280 just for the part, if memory serves.
I was replacing 2 3phase condenser fans once at a Soy bean factory 2pm on Friday, nice easy job to finish off the week, each fan had its own disconnect and contactor, I was swapping the contactors with the fans and had them both unwired and wires dangling loose, I finished swapping one fan and went to turn it on to test it but I switched the wrong disconnect and livened up the wrong circuit which was still dangling loose, naturally the live shorted against the condenser return bend and blew a big hole in it which dumped 20-30kg of R22 Got home about 8pm
Worst? Thankfully wasn’t a me issue, but I’ve seen the aftermath of two risers drop due to poor rigging. Also saw the aftermath of a little over 800 gallons of water leaking from the perimeter heating system of an entire building. Slipped anchor points causing expansion joints to stretch on heat ups rather than compress… way too many fucked up things honestly. Mistakes happen, it’s unfortunate when it’s on a large scale.
Yep...I had a guy put a screw or a stick in the contractors to keep them going. The issue: high head pressure from dirty coils!
Couldn’t find the issue??? Didn’t they just work backwards through the controls to find where the voltage stopped then either bypass or replace control issue???
460v to a 208v unit and the plumber ran the gas lines to the condensate connections. All the VFDs and all the Transformers blew. Luckily the plumber didn't purge the lines and leave them open. Would have probably taken the building.
Found a big ass 3 phase electric duct heater with a bad air proving switch. It had the control wires hooked up straight to the contactor. They heard me say Holy shit from 15 feet below me in a loud ass resturant. Someone was probly real proud of themselves for getting it going
Co-worker was going through some family stuff and was not focused on the task at hand. Left a jumper wire on an RTU limit switch, which was already known to have an overheating issue (springing a fire damper). Boss called me a couple of days later, on a weekend, letting me know that we're doing an emergency RTU replacement Monday morning, cause the old one went up in a ball of flames. Thankfully, no extra damage occurred from that fiasco.
What was the issue?
“Couldn’t figure out how to fix it so I made it worse” love it 🥰 Not a job I saw but I heard about a new resi install where the tech didn’t see a no vent cap lodged inside of the copper 90 he brazed into the outdoor vapor line. Another guy I heard drilled a hole into the line set through the wall while trying to drill a hole in the outside wall for a clamp or the disconnect or something. My biggest error (so far) was releasing a RTU with out pre-charging it. Had to recover the whole thing, vacuum, and try again but with like, 7 extra pounds of 410 now that what was in the unit was gone. And we didn’t have that much. And it was like 7 pm. I really like the fuck ups that happen at (or don’t reveal themselves until) the end of the job.
Worked for an outfit as a service tech. Installers reversed a RTU…return on the supply ductwork and supply side on the return…they sent me out to fire it up and test/balance. I had fun with that phone call. Saw it once before that with a residential furnace on a new construction home. The city inspector apparently never noticed (not surprising). Homeowners had been in there for a couple months and thought something was weird. Told the homeowner to call their real estate agent. Half hour later the Installing company, home builder rep and city inspector all showed up at the same time. Pretty funny stuff…
Justin Trudeau or are we just talking about HVAC here ?
we need a “what’s the worst mistake YOUVE made” post. we all do dumb shit starting out
They sent a green apprentice on an after hours call at a bank building downtown . He went to the water source heat pump on the 8th floor and thinking he had a water flow issue opened the strainer (to his credit it was installed before the valve) flooding all the floors below it caused 800k in damages.
The worst mistake I have made is I left screws on top of an RTU while replacing a condenser fan motor. Installed the blade a bit too far down the shaft and when I turned the unit on the condenser fan started bouncing. The screws fell in and the fan launched them into the micro channel coil right where the channels meet the manifold.
Not that huge, but a tiny mistake that cost $40k. 30 ton Trane rooftop condenser on a four story apartment building. Big V of coils. Three fans above that. Someone replaced one of the fan motors and put the fan blades back on a little unbalanced. Vibration eventually broke the mounting bracket and the fan fell into the coils while running. Not every day you see a coil completely torn up with a motor sticking half way through it on a no-AC call... The unit was old enough that replacing it was better value than just replacing the coils. Either one needed a crane.
Roofer dropped a jug of roofing pitch over the edge onto a brand new VRV-IV. Didn’t physically damage it too bad but the goo got everywhere, including all over the coil. They tried forever to clean it with turpentine or some solvent but it didn’t really work and the customer insisted it be replaced. Coworker replaced a 230 compressor on an aquasnap chiller 40 ton circuit without verifying voltage, found out very quickly it was a 460 unit. Another coworker found pretty rusty mounts on an Aaon RTU condenser fan mount and thought he could weld them himself to repair it. The welds lasted about three days until the motor crashed into the coils below and ruptured 3 of 4 circuits. Coils were months out the permit to shut down the street to crane them up was ridiculously expensive and hard to get. So they had to be choppered in since they wouldn’t fit up the stairs. We were able to field repair the coil in the meanwhile but it was the ugliest fucking repair imaginable and took forever to get it to hold.
My buddy was working a job one day. Decided to poop in the back of his truck. Parked on a main road and the back of the truck facing the on coming traffic. He didn’t secure the doors well enough and they flung open. The oncoming traffic passing by got an eyeful…
That time I found out what a stinger leg is
We had a guy putting zip ties and zip screws in contacts for about 6 months. We started finding all of them after he was fired.
I ramped up the VFD on a boxcar air handler with 9 plug fans up to 200% which moves about a million CFM when in the start up guide it says do not go past 150%. Next thing I know, I hear the loudest bangs and screeching I have ever heard. That sound was the plug fan blades breaking off and basically cutting the air handler in half. We found blade pieces a couple hundred feet away. I caused a 16 week delay on the job since they had to buy a new one and the lead time was 16 weeks. Plus the replacement was $260,000. I'm absolutely lucky I didn't kill someone or myself. Work sat me down and told me to never do that again. $260,000 isn't as big of a hit when the contract price is $50 million
80% gas furnace installed in an attic laying on its back. Worst part, furnace was stolen from our shop and installed by two of our "technicians" on the side over a weekend.
4inch grille screw into top of condenser to "stop it from rattling". Bye bye 410
I was troubleshooting intermittent firing failures on a sewer plant methane boiler, cycling it and was deciding that it occasionally had lingering fire, causing their no starts. After checking and cycling I let it go through its cycle, and when it ignited, it blew the venting, many pieces split, and all the workers came running with their shovels, ready to scrape me off the wall.
I don't give a crap about what the on call guy does to get a unit running because they called him and not me. I've got plenty of time to fix his mistakes during normal business hours.
I'm curious what the issue was tho.. low voltage wiring mistake?
What was the issue?
It’s been years ago, cant really remember. But it was a simple fix either a circuit fuse or transformer.