Probably back emf generated by fan rotation hitting compressor. Can be fixed with double pole contactor with fan hot moved to bottom. Isolates fan from compressor.
That is not an ECM fan motor on that unit. The it’s definitely a known issue. With TRANE/ American Standard units going back to 2020 16 SEER units and 14 SEER. Seems like we are getting more calls about this on newer units now. We’ve had about 4 this summer so far. Their is a bulletin about this from AMS/ TRANE engineering department. It’s been mentioned already. Change to 2 pole contactor and move run winding for fan motor to L2 from T2. Same way all Carriers come factory wired. Engineering dept states it’s a back EMF issue.
yeah, back EMF from one or the other, probably compressor/cap combo hitting the fan motor, that would make the higher pitch bang, especially since it's hooked to giant noise emitters (the top and blades). compressor is generally a dull low tone thump.
It's caused from the fan motor. Disconnect the compressor and it'll still make the noise upon shut down. Usually only does it when the pad is not on regular ground but on rocks or cement. Tighten the fan mounting bolts as tight as you can by hand and put vibration pads on all 4 corners of the unit. It's worked every time.
Although there may be some back emf factor with these units causing the fan to jerk, I believe the actual clunk can be coming from a loosening of the fan blade shaft bolt. I observed this happening with an Am Std Silver Series CU about two years ago. The noise started like the sound of these units and gradually worsened over a week or two. It eventually resulted in the fan blade falling off the shaft and damaging the compressor discharge line as well as the blade itself. .
there is another youtube tech who installed Carrier and had the same customer complaint. A loud bang when turning off. He installed a delay timer to turn the fan off a few seconds after the compressor shutoff. It worked well. The noise was completely gone. Just an anomaly that the one specific unit resonated when turning off. Staging the shutdown solved it
Your customer should hear my water furnace compressor at turn off. 14 years old and it has hammered at shutdown from day one. Still running fine. Great videos Ted
Dam for the money you have to spend on these units, it really shouldn’t make any unusual sounds or vibrations cycling through a shut down sequence ? that would probably indicate a less than optimal life span of trouble free usage down the road? It’s like buying a new car with a bad bearing in the engine, it’s all good until it runs out of the manufacture warranty down the road and then it’s on your dime. Just change out anything & everything in that unit under the factory warranty… until it sounds right. make it run like the other unit next to it does. Kinda hard to tell a customer that “oh it’s ok that’s normal”, when you have a comparison unit sitting right next door and it’s working without the issue.. When you’re retired and done and that unit kicks the bucket down the road , their in for more downtime and aggravation..
Forever grateful for your a videos, first summer as a service tech and you ans your videos have helped so much. I see so much wrong in a majority of homes I work home , super neglected and i get overwhelmed. I end up at your channel, thank you sir!
I had a Trane 5 ton unit installed in my new construction 8 months ago and it has the same loud noise when the unit shuts off! The unit runs great and really cools my house in southwest Louisiana. It has been really HOT and Humid down here this summer too!
ive been working with newer compressors. the ones i learned on in school dont necessarily make that noise because they are older units to be trained on. on the case with the newer compressors, they all stop like that. i just worked on a year old system and when i pulled the disconnect it make that exact same noise. its a manufacturing issue as far as im concerned.
Always honest and professional love it brother ❤ not every call is a win but we stay professional consistently finished my last call as a recall was out there last week for annual maintenance she calls us today saying system is down come out right away she explained to me she had a pest control out there two days ago the pest control guy left the power off in the crawl space which killed power to the unit always feels good to be Superman flipping switches
I have a new 3 year old system, not a Trane, that does the same thump. Mine is more at start up. I questioned it as well and was told that all the new style compressors will do this, clutch noise I believe
Interesting...if those were mine and under warranty...I would for sure be communicating with Trane ! Yes very minor but NOT really normal so Trane should correct it. By the looks of previous comments, maybe it should have a dual pole contactor?
that sounds like normal the valve noise. When the compressor stops there is still head pressure and motor will shutter back and forth a few cycles until the opposing forces equalize and the motor stops in a neutral position.
I have two carrier units that makes a similar noise on start up. Both units were installed when the home was constructed in 1999. They continue to perform effortlessly in the humid Louisiana climate.
The scroll compressor , upon shutdown will make that noise . It's the pressure in the system that actually pushes the scroll backwards for a brief moment. It is Totally normal. On the trane csha scrolls (15 ton) upon shut down they actually turn bakwards for up to 2-3 seconds. Take is easy bro.
That sounds like the reasonable explanation. The early type rotary used to tick while equalizing. Back EMF,resonance,moving loads around.IDK about that shyt.
Yeah idk what everyone is talking about the fan making the noise, bigger scroll compressors do it unmistakably so that’s probably why I know it’s the compressor
Do you think that the compressor could be loose and when it torques on shutdown that it moves slightly? That definitely doesn't sound good (acceptable) on the first unit especially if it's new. I'm not in the business but as a consumer if I paid to have that put in I wouldn't want it to sound like that.
Sadly it is just the sound they make on shut down. The compressor becomes torqued in one direction while running and the sound is the compressor immediately releasing the torque.
I would first check the mounting of everything. If it were a car, i'd check the motor mounts. With this, i'd go for the fan, compressor and even the unit itself. Trane may have left out a rubber bushing.
My Trane is doing same thing. My Tech said if I installed a soft start it would reduce the start up and shut down noise. It didn't help at all. Did I get scammed?
Compressor sounded fine on shut down… sounded like the fan motor to my ear … I have had the same complaint from customer that has a Trane package unit.
Looks like the installers could turn some of the units 90 degrees to allow for easier service, the control panel and service area, if heat pump would be a lot easier to service
Ted, Please don't oil that squeeky hinge on your work van, we all look forward to that squeek when you arrive at the next job, and open the door 😀 👍 Au
I have a 2023 amer Stan silver that started doing this 4 wks after install. The installer tells me its normal with the new compressor design. I wish they could do something to quiet it down. It runs quiet and the entire system with blower installed. It’s going to get used a lot in Az. Kicker is if the rotary designed compressor wears out the entire compressor needs replaced. 10 year warranty I hope has me covered if it happens.
I have one that makes 10-12 knocks on shutdown. Sounds like someone threw a handful of rocks at it. My service company ordered me a new compressor (scroll) but said to wait until the old one failed as it was working perfectly and using no more electricity than a new one. That was three years ago and it still works perfectly just noisy on shutdown. I don't know if it is a rattling seal or what but pressures are perfect. I just knew it would throw in the towel a long time ago but it has not.
I bought a brand-new Amana 4 ton, and it does the same noise at stop. I thought was the fan blades, but I stand closed to the compressor and I hear from there and it feel like clan,clan,clan when is stop. it looks like the compressor when it stop. Maybe cause its bran new and the piston inside do that.
had my compressor on my new 2021-22 trane unit go out at 13 months. original compr indicated made in louisiana. replacement was proudly made in china. maybe pandemic conditions resulted in reduced quality control on new trane. but if a trane laid down after a year can you expect any mftr to be reliable?
Trane does not use Chinese compressors. Some have LG compressors, and those are made in Korea. Most include an Alliance, and they are still made in Louisiana from what I have seen. Maybe yours was a certain batch.
sure would love for you to show me, I always want to learn how to get a customer off my back lol. please make a video on your solution to prove your hypothesis.
So youre telling me they designed that ac unit to make that kind of noise? I cant believe that. If the customer had the opportunity to “test drive” the unit before they purchased it nobody would buy one. I spent $20k to have 2 american standard units installed and they make the same noise which I was told is normal. I will never purchase that brand again or use the contractor that sold them to me.
should a newly installed compressor make noise on start up ? like cavitation or a "rod knock" on start up ? I'll have to record it, BUT, I am not getting the same idiot who came out the last time. Yes, coincidently I had a FIRE in my fuse panel starting at the AC circuit breaker WHILE he was here working on the unit.
Not very likely. They are torqued at the factory. Occasionally that may be the case, but not very likely. It is the sound that a scroll compressor makes when shutting down. The noise could actually be reduced by loosening the bolts just a little, but make sure to dab a bit of rtv across the bolt to prevent it from backing out more.
I usually have to be standing around 15 feet away to isolate the compressor vs fan sounds but from the video it sounds like something is missing from the functionality of something 🤷🏻♂️ if they donate that unit to my not for profit conditioned space laboratory I could send them some stickers or maybe a hat
Completely normal. However you would think nowadays they would make even basic compressors quieter. They have the technology just don’t want to spend the money.
Sadly for customers the mfg keep trying to cut cost out and keep function. Notice how much lighter a same capacity, new compressor is vs one from 15yrs ago?
I for one do not believe it's normal, maybe with these two-stage compressors nowadays but it is definitely not normal on a basic compressor, I would like to find a way to drop down to first stage before shut down, I can tell the difference in sound from first to second stage, I have a f****** geothermal unit and as loud as f*** in the house... makes you want to run and go look and make sure you ain't got no lines blown off an flooding your house...lol