Hello All, I got some good advice here in this forum a couple of years ago so I'm back with a new problem. The problem is with our 2 year old heat pump squealing when it first starts up in cold weather. The AC unit does not make this noise, just the HP. Has anyone heard of a problem like this? The noise is more common and louder when the weather is colder, and also more common at night, but does happen in daytime on cold days. It also doesn't happen if we cycle it off and on quickly, like we recently tried when service man was here.
We had this unit installed new in spring 2006 and it is a RHEEM 3 ton 14 SEER HP/AC. It has always made the noice but I'm an idiot and thought they all did that. (Had a BAD gas furnace previously and was so thankful to have that thing out of here that I didn't really care about anything except that I now knew that I would not die blowing up in this house with that gas furnace)
Anyway, we didn't notice the squealing in 2006 because there wasn't any really cold weather after it was installed. Then noticed the squealing on the really cold nights last winter and asked the installer about it when he was out for annual visit, and he said he knew what it was and to let him know if it continued this winter and he would replace the part that was causing this. Well, it did have the squealing characteristic this winter and we finally called and one of the fellas came out to check it out. The initial installer thought that the problem was something with the fan but the service rep that visited did not think that was it. But he did find an old hose from the old gas furnace caught in the bottom door of the HP. It has probably been stuck in there since initial installation. He thought that hose being in there was what causing the squealing and so all was fine for a couple of nights after that, and then we noticed the squealing again.
And the service folks only get one opportunity to hear the squeal when they come out, and that is the first time we kick it on. After that no squeal. And they are coming tomorrow again, but it is not squealing today because the temps are in the 40's and 50's, so probably won't squeal tomorrow either. He still wants to come anyway.
And this noise sounds like a valve or something squealing under pressure. Sometimes the noise is just one continuous squeal and sometimes it changes octave or whatever as it squeals along. Most of the time the squeal lasts for about 5 seconds or so, but in really cold weather it can go on for twice that long or more. And, most of the time it seems like the squeal ends abruptly. (just like a valve finally gets open)
Any ideas appreciated. Unless a different service rep is coming this time, the last guy was stumped. And, since it will probably not do it tomorrow I don't think we will get a solution. I even tape recorded the squealing so they could listen to that but I know that will not be useful.