Checked both heatpumps in heating ,cleaned condenser coils and changed filters . Inspected ducts for air leaks or restrictions and made sure no error codes had been displayed recently . I did find that the upstairs unit was running on emergency heat and when inspected outside unit I found what appeared to be refrigerant residue under reversing valve . I sprayed soap and saw some bubbles but it being so cold .y gauges didnt tell me much . Also got dark out so need to return to look into this issue more .