Quote Originally Posted by NY2GA01 View Post
but this was a heat pump, so the use of a one way filter is like having no filter at all.

Still not a 100% on if it killed the compressor.
Well, it'll definetly filter in the cool mode. I'm not sure if the moisture or contaminants gets pushed back out of the dryer during the heat cycle or the refrigerant simply flows around the core!! Maybe Andy Schoen or somebody could explain?