Heating and Cooling Unit frozen
My heating and Cooling unit (it is new) was frozen (now it is not because yesterday I turned the heating off). It works well but I wonder if it is normal to be frozen when is on. It is located outside the house. Temperatures here are not cold, yesterday was between 56 to 64. Sometime last week were in the 30's in the morning, but mainly in the 50's in the evening. Last electricity bill was very high compared with previous months. Please advise.