Trane is unfortunately known for the last decade or so for using Chinese compressors in some of their units. The compressor may be hidden under a sound dampening blanket.

If I had to guess, that is probably where the noise is coming from.

It is normal for the compressor to make 'some' noise. So without hearing the noise this is my best guess.

With that said I replaced a noisy Trane unit a year ago that suddenly went silent. Fortunately I recorded the noise it made (all the time) while running. Does it sound like this:

I service the Katy, Texas area

Thank you for responding, great video by the way! I received a similar response from the company who installed the unit, just seemed odd to me. You think you are buying top of the line equipment and have this issue immediately after it's installed. The noise only occurs when it starts up but it's loud and sounds screeching or something. My old Lennox unit that was 20 years old din't even make noises like that. I don't know how to post the video I have of the noise but thanks again for responding I really appreciate it.

Videos can't be directly uploaded into a post. Put it on YouTube and link to it (that's what the Video function is for).

Let's see if I did this correctly. Never created a video on YouTube before.

Thank you again, yes I got a lot of pushback from the beginning on this. I had him come out a couple months after he installed it because of this issue and I installed this about 1 year ago exactly. he made it seem like i was just complaining and that I just got a loud start up unit (and it happens some times, in his words) so I let it go until it started doing it again this spring when it got warmer. I shouldn't have to get a brand new unit and start replacing parts immediately was my argument and knowing nothing about ac units, just didn't seem normal to me.

My unit, a 16yo Carrier, has been noisy like the one at 1:14 in Austin Air's video for more than 10 years. Possibly 14 years. Still running. Neighbors are far-enough away that they don't complain.

My unit, a 16yo Carrier, has been noisy like the one at 1:14 in Austin Air's video for more than 10 years. Possibly 14 years. Still running.

Maybe with everything going on in the world, your neighbors have realized you are doing them a huge favor.......(lol)

so they came out today and have now replaced the contactors, expansion valve, compressor and fan motor and the unit is still making this screeching noise? What else could this possibly be at this point? I'm at a loss and feel like they might be as well.

Are you sure they replaced the compressor?

That is the source of the noise. (They would have had to take that outdoor unit apart to replace the compressor, in some cases all the way down to that plastic base pan the unit sits in. (because no room to get to the compressor)

First of all, I take it the "screeching" you are referring to is the buzzing/rattling on startup. Sounds like something loose, rattling inside there although that noise is pretty common (not "normal") from a contactor or compressor. I'm pretty sure they didn't "replace the compressor"! Most, brands would just replace the entire condenser if the compressor goes out during the first year.

I'd be highly suspect of what they claim to have replaced!

Most, brands would just replace the entire condenser if the compressor goes out during the first year.

Yep, even a generic brand I occasionally sell / install has a 1 year unit replacement if there is any compressor trouble. (conditional -- only applies to compressor trouble)

I have no idea why I didn’t get a replacement unit. He said Trane wouldn’t do that. im pretty sure they replaced the compressor though. Took a few hours and they took Most of it apart. It also sounds like it’s buzzing now pretty loud where it wasn’t before.

I'm pretty sure it's the old Trane arrogance in which they think their equipment is something special.

I grew tired of that song and dance, often times blaming the techs as improperly diagnosing a failure or whatever their excuse of the month is.

With that said, it's only going to get worse. I'm pretty sure you paid for a working system. I know if it were me, I wouldn't accept this.

You have another system sitting right there, record the noise it makes on start up. Then go make some noise to Trane.

In my book this is unacceptable.

Thanks, I agree I guess that’s what I will have to do at this point. I don’t know much ac units but I know this isn’t right for a new unit. Very Unfortunate.

Austin Air, so they replaced my unit but this unit makes an extremely loud humming noise when it’s on. I can hear through the walls inside my house. Any idea what this could be? I never hear the second unit when its on, ever And this one sounds like a generator.

That's probably worse than the previous noise?

From your video I can see you have two disconnects on the wall of your house.

The disconnect (grey box) on the wall there should be a plug or switch in there. With the unit running, reach in there and either pull the plug out or turn the switch off. The outside condenser will shut off. (The indoor unit will continue to run)

-- this doesn't hurt anything.

Do you still hear the noise after you do that? Where is the noise coming from?

If the noise only comes from the new unit while it's running -- time to call up your installer again.

You're on the path to turning your Trane dealer into a 'former' Trane dealer.

"But this equipment is the best you said..." -- there's a river that runs parallel to that comment. It's called DeNile. That only lasts so long. LOL.

@Austin Air Companie I'm in the Phoenix AZ area and I have this exact same sound coming from a 9 month old Ruud 2 stage 4 ton Achiever Plus unit. It's infuriating to me that a brand new unit is broken. My installing contractor seems stumped and has been less that responsive basically taking the stance of "well, it's still cooling". There is obviously something wrong with the compressor. After 3 trips out here, prodding him all the way, a call to Ruud's tech support, he's decided to replace the compressor and install what he calls a "reverse trap" in the suction line in the attic believing that liquid refrigerant is flowing back to the compressor during the off cycle. I really don't understand this theory since it's been over 100 degrees for 2 months, the noise is worse when the unit is in full sun. Does this sound right to you? I'm really considering dumping this guy, calling Ruud and demanding a new condenser unit and contractor.

@Josh Prince did they get your issue figured out? What was the fix?

Hi Jeff, my guy ended up replacing the compressor and it didn’t help. Pretty much everything had been replaced. Might have been the coil. mine did the same thing, was always worse in the heat and after it had been running a while. He replaced the unit eventually and it’s been fine ever since. Good luck. It’s very frustrating I know especially with new units.

My guy also mentioned the liquid refrigerant issue but there was no crimp or anything to support it.

@Josh Prince when you say "replaced the unit" do you mean the condenser unit on the ground outside? Or did he replace the evaporator coils(indoor) as well?

Jeff Davis, yeah any brand can suffer from this problem.

Irregular compressor noises are an indication of failure so because your unit is new it should not be making these kinds of noises.

With that said, noise is subjective. A condensing unit will make some noise when it is running.

Refrigerant migration can cause these kinds of noises but not likely in the summer time because refrigerant migrates to the cooler part of the system. Which during the summer is most likely inside the house most of the time.

Certain manufacturer's want to see a backwards suction loop, but I think this is really just them wanting to avoid a warranty claim. It might help on some installs, but I doubt it will matter much as I believe this matter is more about improper installation.

I have mismatched equipment, installed new equipment, repaired systems with other brands... never had this problem with any of my installs other than the one I posted in the video above... but that one was making that noise before I started working on it, until it eventually died a slow and painful death. (poor guy)

Proper installation: in a nutshell that's what it means. (you won't have these kinds of issues.)

Maybe the noise is due to air in the system or some other thing that doesn't compress. Essentially that is what the unit is telling you when it starts and makes an irregular noise. (I am a suction gas compressor, not a wood chipper -- you know if the compressor could talk what would he say?)

I service the Katy, Texas area.

Thank you for your response sir. I’m very frustrated with this situation a feel like I was sold a bill of good with promises that didn’t deliver. I replaced the whole system hoping for better efficiency and reliability. Now here I am in a similar position as last summer with a system that is not healthy and a contractor that is less than responsive, and doesn’t seem to know what the problem is. That said, I will continue to deal with him because I think I have to at this point since he installed the system.

Jeff, Yeah unfortunately there is no one else to come in and pick up the pieces of a poor install with problems. The installing contractor / Ruud distributor need to work together to get this problem resolved.

Jeff, they replaced my outdoor unit only. Hope that helps and good luck, I know how Frustrated it is

Thank you for the response Josh. I just hope my contractor figures it out.