Replaced an old 5 ton air conditioner with a pair of 3 ton 20 Seer heat pumps in a zoned configuration in April. The new units, even with both running are very quiet and vibration free. ~50db at 3 feet outside. The new units sit on a rubber pad which sits on a concrete pad about 6 inches from the house.
Inside the house in the room above the furnaces and where the pipes enter the house, the noise is unbelievable - >80dB with an annoying resonance and vibration that could be felt in most of the house. You can't be in the room when either is running. The furnaces are quiet. Had the installers back and they have no idea what the problem is.
So I Googled ........ and problem solved.
Both sets of refrigerant lines are each covered in a pipe insulator. Every 3 feet over the ~20 foot span the pipes are tightly tie wrapped to the basement joists. I cut the tie wraps and pulled the pipes away from the joists and the noise reduced 80%. I wrapped the pipes in another layer of pipe insulator (~2 inches long) and re- tie wrapped loosely to the joist clamps. Where the pipes entered the house, the pipes were resting on the concrete foundation wall and caulk used to fill the hole. I dug out their caulking, positioned the pipes in the middle of the hole, used some strings to temporarily support the pipes to keep them centered and re-caulked. That eliminated the noise and resonance. The room above the furnace experiences no sound now.
The root problem: somehow the energy in the pipes caused vibrations in the joists and wall because they were so tightly clamped, even though they were wrapped in pipe insulator. It wasn't just the loud noise that caused problems, it was the annoying resonance that carried throughout the house.
Thought I'd pass the info along.
Inside the house in the room above the furnaces and where the pipes enter the house, the noise is unbelievable - >80dB with an annoying resonance and vibration that could be felt in most of the house. You can't be in the room when either is running. The furnaces are quiet. Had the installers back and they have no idea what the problem is.
So I Googled ........ and problem solved.
Both sets of refrigerant lines are each covered in a pipe insulator. Every 3 feet over the ~20 foot span the pipes are tightly tie wrapped to the basement joists. I cut the tie wraps and pulled the pipes away from the joists and the noise reduced 80%. I wrapped the pipes in another layer of pipe insulator (~2 inches long) and re- tie wrapped loosely to the joist clamps. Where the pipes entered the house, the pipes were resting on the concrete foundation wall and caulk used to fill the hole. I dug out their caulking, positioned the pipes in the middle of the hole, used some strings to temporarily support the pipes to keep them centered and re-caulked. That eliminated the noise and resonance. The room above the furnace experiences no sound now.
The root problem: somehow the energy in the pipes caused vibrations in the joists and wall because they were so tightly clamped, even though they were wrapped in pipe insulator. It wasn't just the loud noise that caused problems, it was the annoying resonance that carried throughout the house.
Thought I'd pass the info along.
