Okay guys, Mom and Dad called me last night. Their XR12 heat pump is making a chattering noise when in Heat. They keep T-stat on 73 during the day and lower to 71 at night. Today the OT was 76 so I didnt kick in the heat, going tomorrow morning. Could it be a CAP tube vibrating on something? Caused by the reverse flow of 410a?
could be alot of things.....check contactor, reversing valve.
Could be a relay on the defrost board.
The noise is comming from inside the airhandler. Dad assured me of that. Thats why I'm thinking a CAP tube, maybe around the TXV. You know how those things run "wild" in Trane units.
Trane uses a check valve that is basicly a peice of copper with a steely ball in it.
It allows refrigerant flow in one direction and closes when the flow changes direction. (heat pump vrs air cond)
When in the 'open' position... the steely ball can spin around wildly and cause a 'wizzing' noise and/or a 'chattering' metal to metal noise.
I have seen... err heard the 'wizzing' noise mainly when its running and the 'chattering' noise when they shut down and the pressures are equalizing (goes away after a few minutes).
The fix is the same for both probs.
Get a magnet (a peice about 1/2" x 1/2" has worked fine)
If you know where the check valves are, then while its making the noise, rub the magnet along it till the noise stops. Then take some electricians tape (hehe one of the only good uses I've found for it) and tape the magnet to the side of the check valve.
Check for correct operation in both modes... heat pump and cooling mode. And you're set.
I hate running across this prob cuz I keep having to use my 'one and only magnet' that I save to get metal shavings out of my eye (I religiously wear safety glasses, but the dang things love to jump in my eyes... I think I must have magnetic eyeballs or something muahahaa... just kidding)
In looking for a link for a place to buy magnets... I remembered something...
Be careful not to get some killer magnet (rare earth magnet)... they might be a bit tooo powerfull and not let it function right hehe.
You just need a plain jane magnet.
LOL, think I'll try that as a LAST resort wormy. Gonna see if I can find exactly where the problem is first. Good idea though.
The problem just may be the check valve in the air handler. Trane has a kit with a magnet and clamp to resolve this if this is the problem. Also, make sure the refrigerant charge is correct, this can sometimes cause noise problems. If it were the cap tubing vibrating it would usually be a more consistant noise problem.