Hi,

My manufactured home is heated/cooled with a heat pump. When the cooling or heating shuts off, occasionally, there is a sharp single pulse that co-occurs with the termination of heat/cooling that rattles the house. This doesn't happen all the time, maybe 1 in 5 times. Sometimes when the heating/cooling shuts off, it is quiet and makes no noise.

The heating and cooling works fine. I can't seem to replicate the noise by manually shutting off the blower fan, so I assume that isn't the problem. The few times I stood outside next to the heat pump when it shut off, I can't hear the noise.

Does anyone have any thoughts as to the specific problem, or how to narrow down the search for the problem and should I be concerned about it?

Eric

It could be the old oil can syndrome. This is the duct expanding and contracting. Those problems are very hard to find. The metal in a mobile/manufactured home is usually very thin aluminum.