We had a 5-ton Bosch TA061 (closed loop) geothermal installed in late February. The Copeland scroll compressor creats a low frequency throbbing/thrubbing sound throughout the house.
Our installed is a pro, and the Bosch rep has been at our house twice. All eight points you raised have been addressed and the pros all tell us this is a "quiet" unit operating within specifications.
As a last resort, two weeks ago we voided our 10-year warranty and re-located the compressor to the garage, 45' away from the unit. Unfortunately, the throbbing is coming right back into the house through the copper tubing.
We installed a "vibration eliminator" which doesn't eliminate vibrations, it simply reduces the chances of broken connections caused by the startup vibration of the compressor. This weekend we installed a muffler on the discharge side of the compressor which reduced the noise decibels by 9%....not enough to matter.
The tubing is insulated with a foam sleeve and is running in a floor joist. It's nearly impossible to hang it so it doesn't touch anything although I've done my best. To do a better job, I'll need to rip out lots of drywall ceiling but I'll do it if I can't find another solution.
A couple of questions:
1 - We have the compressor screwed down tightly to the concrete garage floor because we figured if it was on its original hard rubber base with set-off springs, it would only vibrate more. Does this make sense?
2 - Do you know of any product that can short-circuit the vibration from the compressor to the tubing? The discharge side vibrates more than the other. A previous post mentions: "Lennox does have a pre-packaged noise suppression kit. It installs on the suction line in between the compressor and the service valves." Do you know if this works?
3 - Do you have any other ideas that might help? If we don't find a solution, I'm going to pull this out and burn thou$ands of dollars.
Thanks for your help and consideration.
I know this subject has been posted many times and I've read most of them. Yours was one of the best so that's why I'm responding to you rather than starting a new post, but I will if you think that's the way to go.
David in Ann Arbor, MI