Can anyone refer me to- or tell me here- about why my heat pump doesn't seem to be heating? The ground floor one works fine, sometimes with the 'Aux. Heat' light coming on, and 'Emergency heat' a choice we never switch it to. That one has heat strips added as part of the house inspection/sale, the top floor one still has no heat strips in it. We rarely turn on the heat upstairs since heat rises and the computer room is up there and really heats things up. However with night temps 30's and day temps only 50's we've sort of wanted it on a few days lately but it only pours out cold air (BTW registers upstairs on ceilings, downstairs are on floors) and we've given up on it. Today (without complaining sleepers under the vents) I tried to raise temp up there and don't think I did- it actually perhaps went down from 65 to 63 degrees (but bet the back rooms were warmer just from spreading the air around). Also the outside unit's fan is not turning on for the upstairs when it was putting air through the registers unlike the downstairs one. So that absence of fan means it's not working as it should, correct?