Trane XL14i

[hrc]

I recently had two XL14i heat pumps installed, 1.5 ton second floor, 2.5 ton first floor. The 2.5 ton is very quiet, but the 1.5 has a noise coming from the compressor. Shouldn't both have the same noise levels. Interesting enough the 1.5 appears to have a larger compressor based on the compressor cover sizes.

[Irascible]

Sound quality is product of the installation and not just the equipment. If both outdoor units are on the ground level but the air handler for the upstairs unit is in the attic, then the upstairs unit has to push its refrigerant against a much larger column of liquid. In other words, BTU for BTU it's working a little harder than the downstairs unit to accomplish the same task.

That is not to say that your problem is normal. In reality I have no clue why the sound quality is so much different. The upstairs unit should be able to run fairly quietly despite the circumstance I just described. Being overcharged is a definite cause of a noisy compressor. You may wish to ask about that. Obviously you need to have your installing contractor address this.

[hrc]

Thanks. The distance to the airhandler in the attic is approx 43 ft, the downstairs distance is approx 27 ft. Good info to have ready for the installer when he comes back wednesday.

[hrc]

Irascible,

Forgot to ask: The upstairs unit (1.5 ton) has a 1/4 refrig line and a 5/8 suction line, is this adequate for the application?

[Irascible]

I took a look at Trane's application guide for refrigerant piping. Even with the 43 foot length and the 20 foot lift those line sizes are acceptable (unless you have a LOT of turns and elbows) for both R-22 and R-410A systems. 410A especially has plenty of head room in that regard.

Just a wild theory: 1/4 inch tubing is so small that it wouldn't be hard to accidentally partially fill the tube with brazing alloy (or refrigeration grade solder) when the lines are being put together. If that happened then the unwise and/or uninformed installer might be tempted to add excess refrigerant to compensate for the restriction. IF that happened you would most certainly get a noisy compressor as a result.

[hrc]

I am just a dumb homeowner but the brazing material drop through theory did occur to me since the technician was applying the material heavy according to him, and he also had to rebraze to correct a leak. Good info, thanks

Homer

[Irascible]

Another way to determine an overcharge is to find out how much refrigerant was added. Even with the length you'd probably only need to add about one-half to three-quarters of a pound of refrigerant.

[Irascible]

Just to add fuel to your already worried fires: Did they purge the lines with nitrogen when they brazed? If not then ash formed in the lines. The ash can collect at the metering device and cause a restriction. And again they could have compensated by adding extra refrigerant. That can be even harder to diagnose.

When you have a restriction in the middle of the line then from that point on the line is often noticeably colder than before the restriction. But if the restriction is at the metering device then you won't be able to tell by feeling the temperature of the line. You’d end up with high head pressure, high subcooling and a noisy compressor - though it would most likely still cool. If you have those symptoms then they’ll probably need to pull the refrigerant out and take a look at the metering device.

[hrc]

You are right on the money....they added 11 ounces.

[Irascible]

Hmm. Then it shouldn't be grossly overcharged. Though if I had to add two pounds to a system when I know I shouldn't of, I wouldn't exactly document that. :^)

Anywho, don't bang them over the head with this thread. I could be off my rocker. You could have unreasonable noise expectations. We don't know yet.

[hrc]

I have been known to be unreasonable but this time I have a standard to compare it to, the other new very quiet unit sitting beside it. My wife can even tell the difference which says alot.
I really appreciate your help.
Homer

[j-bill]

Most likely noises in the new 14i are from a simple hot gas pipe up against the plastic base of the unit,i will find this alot on new units,just takes a little bend,an suprise homeowner no more noise,But Please! No contractor wants joe homeowner directing him on diagnosing problems,had too many times joe homeowner with too much time on the internet coming up with garbage ideas he read from web sites, let the pro's do their job, don't try to micromanage the contractor,if not satisfied contact the manufacture,they have field service reps that will help you get the problem cleared up,most good dealers will contact the FSR on their own,if they are having trouble figuring it out.This is a message to all homeowners who post questions on this forum,this is'nt a DIY forum or a get ammunition to ride the contractor forum please! there are too many variables in diagnoising problems in the hvac trade,Let the Pro's do their job.PLEASE!

[Irascible]

I take it all back. Bill is right. We must not disturb the delicate genius that is the typical HVAC contractor.

But wait... The typical HVAC contractor is a dolt. That's just my opinion and I'm entitled to it. You forget Bill that contractors on this forum are just a little smarter than the average bear. And certainly we've come up with no bad theories. But if you think so then I guess hrc can't say anything about your discharge line observation. We wouldn't want to annoy his professional technician who likes to apply ample amounts of brazing alloy with our garbage internet theories, now would we?

[hrc]

Irascible,

Yesterday was my first on this forum, which is great because of professionals like you. I and others appreciate your time.

For the record when most homeowners like me ask questions it is not to position ourselves to lecture the people we hire to perform services it is to educate ourselves so that we may understand the issue.

I don't understand people like this j-bill person, however based on his inappropriate comments I would not trust his ability to install a window fan in my house.

Keep up the good work.

[Irascible]

Exactly right. You didn't come off as pushy and no one said anything about banging your technician over the head with a printout of this thread.

In Bill's defense his comments are entirely appropriate for some homeowners. And no doubt he's experienced the customer who second guesses every one of his moves. So perhaps he's sensitive to such things. I just didn't see how it applied to this thread.

In any event, don't let that stop you from asking about his garbage internet theory regarding the discharge line. There's nothing wrong with asking questions. And his garbage could be right.

[Mr Bill]

Originally posted by hrc
I would not trust his ability to install a window fan in my house.

0 My God!!

[j-bill]

Irascible: My point is your trying to plant a bad install possibility to this "known to be unreasonable hmo",is a perfect set up to ride the contractor before any diagnois is complete,no disrespect on you,but thats the way i've see it. Alot of times more than not, its just simple crap causing the noisy unit. and hrc thank you, i can't install the window fan GOOD LUCK!

[hrc]

Let me make it clear: this is not an effort to blame the installer, I have used this company for the last 22 years, the owner lives two streets from me, I am only trying to get info so that they will not have to answer any unnecessary questions. This is a very busy time for them, reality is: the install could incorrect, the unit maybe defective, this maybe a typical situation, I could be oversensitive. Irascible is only providing info, you y-bill overreacted.

Irascible,if wed ever gets here I will let you know the outcome.
Homer

[Irascible]

I understand what you're saying Bill. I think our differences are in matter of degree and not principle. I don't think I've made any attempt to evaluate the install. I'm a service tech trying to troubleshoot a very specific problem. That's one aspect of an install, not the whole shebang. YOU even contributed help in that regard.

In fact, I even said the following before you joined:
"Anywho, don't bang them over the head with this thread. I could be off my rocker. You could have unreasonable noise expectations. We don't know yet."

[hrc]

The Trane technician verified pressures, line temperature, amperages, valve, structural integrity and found no problems. He agreed that the 1.5 unit was noisier than the 2.5, called his supervisor and was told that the compressor would be replaced. Is there some other characteristic that should have been measured. I am suprised that they will replace the compressor, the unit is only a week old.