I purchased a new Amana heat pump (ASZ14) with a variable speed handler this summer. It cooled fine, but now as it gets colder I'm experiencing an issue.
Whenever the auxiliary heat comes on, whether due to temp or entering defrost, the blower apparently enters into it's second speed. The noise at this speed is that of a jet engine, at every register. There is only the single return (14 X 20). I'm using a pleated filter, which I've tried removing to no effect. The loud blowing is constant, not gusty.
Is there anything I can do to combat this? Or is this simply a case of the return, registers, and/or duct being undersized? And if this is the case, why did I not experience this noise/speed during an entire summer of cooling?
Thanks for any help.