Heat pump condensers freezing over
Checked the defrost cycle times yesterday. There are three choices - 90min, 60min and 30 min. Both condensers were set on 30 min so unless neither consenser is working properly (Highly unlikely, I would think, on both units), any ideas what else could cause both systems to freeze over? (They weren't solid blocks of ice but they were pretty much covered with frost, top to bottom and inside to outside and not working efficiently (aux heat coming on, outside temp above freezing).