Unusual Heat Pump Problem
I have an 11 year old 2.5 ton heat pump. Heat pump running in HEAT MODE, no aux heat. When the outside temperature is 50+ degrees, the output register air is around 70 to 72 degrees. When the outside temperature is BELOW 45/50 degrees, the output register temperature (no aux heat) shows a rise of about 30/35 degrees, or 80 to 90 degrees temperature. Cannot understand why when the outside temperature goes above 45/50 degrees, heat pump stops putting out hot air but basically equals the indoor temperature. Below that level, works fine. Temperatures below 30/40 degrees with outside humidity, frost lines develop as expected and defrost mode works great - no build up of frost or ice.