Loud Click/Clunk when Condenser Shuts Off

[Clocker]

I have only heard my newer (2-month old) Bryant 116B do this twice. And it only seems to do it when it is cool outside like I describe below.

Last night it was about 65F outside, the temperature had dropped pretty rapidly outside. But, my air kicked on because it was still warm in the house and I had the windows closed. The condenser is right next to the outside wall of our bedroom. When it shut off, it made a loud sound that sounded the a cross between a click and a clunk that I could hear inside the house.

I have only heard it happen twice (different days) both times it was relatively cool outside (cooler outside that inside the house) Is that normal?

I have no complaints with system performance, otherwise.

Thanks!

[catmanacman]

I would call the installer back to check it

[Clocker]

I'm working on getting my contractor out but wondering if any of you guys want to take any guesses as to what the sound is:

http://www.youtube.com/watch?v=GuYsDH6QSog

It's at about 8-9 seconds into the video. You have to turn the sound up in the video, it recorded kinda quiet. The sound seems pretty loud in the house, maybe because the line-set is rigidly connected to the masonry with cement...

Thanks,
Clocker

[Clocker]

Sent the video to my installer last night prior to them coming out today. He said it sounded like the 'valves are shutting'. Not sure what that means though!

Tech will be out tonight but I'd like to know if you guys agree with the assessment and if you could provide an explanation of what you think he means?

[timebuilder]

It's the same sound that I hear most scroll compressors make when they shut down, and the scrolls unload. I'm not sure why it would be quieter, when its cool out, but I CAN tell you that a cooler ambient means lower pressures on the compressor's discharge side, and that means less pressure in the scrolls right before the scrolls unload and push away from each other.

I would consider this to be a normal sound.

[Clocker]

Thanks.

One thing I have found is that the line-set is rigidly connected to the outside wall (concrete used to fill the hole) instead of the method shown in Fig. 1 page 1 of the install manual (link below). It is making hard contact with some of my joists inside the house as well.

According to the manual, "In some cases noise in the living area has been traced to gas pulsations from improper installation of equipment."

Maybe that is exacerbating the noise.

Nonetheless, the installer told me that everybody does it the way they did it.

http://www.docs.hvacpartners.com/idc...3a-116b-07.pdf

[HVACTechNC]

Your line set should be sleeved through any masonry so it does not come into contact with brick or mortar. Not everyone does it that way. In fact, contractors who desire to be code compliant do not do it that way.

[heaterman]

We sleeve, insulate and seal all line penetrations and do not fasten line sets to joists tightly. We try to allow for a little movement to allow for expansion and not tranfer vibrations. As far as the noise, I have had units (scrolls) in the past that sound about the same, still, no harm in checking.

[Clocker]

Tech was out. My unit is operating normally. He said he called Bryant and their tech. support told him that on cooler days (<63F) there's an imbalance of pressure in the system somehow related to the TXV that causes it to make the noise/vibration upon shutoff.

I'm glad the unit is OK but still unhappy with the way the line-set was run through the wall. I feel the noise would be quieter if it had some isolation from the house but my installer is not willing to change the installation to make it like the installation manual shows. Guess I just have to live with the noise on cool days or do it myself. Not to excited about trying to chip out the concrete adjacent to the line-set though.

Wish I would have used a different installer (the one I used for my furnace was far superior) & am disappointed that I got the extended parts/labor warranty though them. I don't suppose there's some way to transfer it to another contractor?

[Cooked]

The alkali in concrete or mortar will "eat" at the copper it touches but it takes a long time. If it's just mortar it will be soft and you could carefully chip it out if it bothers you and replace it with a resilient material like silicone. That being said it will acoustically and mechanically couple vibrations into the house.

The clicking/clunking noise is nothing to worry about.

[heaterman]

Unfortunate that your installer has that type of attitude. If you attempt the repair, just be extra careful not to damage the lines. Slow and steady wins the race.

[HVACTechNC]

Wish I would have used a different installer (the one I used for my furnace was far superior) & am disappointed that I got the extended parts/labor warranty though them. I don't suppose there's some way to transfer it to another contractor?

Typically, extended parts/labor warranties are offered through equipment manufacturers and then resold through the local contractor. Your warranty should be through whoever manufactured the equipment and any authorized dealer of that equipment would be able to honor that warranty. Check on that to make sure it is true in your area.

[Cooked]

Typically, extended parts/labor warranties are offered through equipment manufacturers and then resold through the local contractor. Your warranty should be through whoever manufactured the equipment and any authorized dealer of that equipment would be able to honor that warranty. Check on that to make sure it is true in your area.

Good point. Many warranties outlive the original installers through deaths, going out of business, retirement etc. The manufacturer will stand behind it.

I commend the homeowner for taking the time to even read the installation instructions. Most installers don't or won't because of the "everybody does it like that" attitude.