I purchased a Kenmore Heat Pump June. From June to October my house was empty and the heat pump was not used.in October the house became occupied and the heat pump went into operation for the Winter. From May to August the heat pump has been one problem after another other. Every two weeks the Air Conditioner would stop working. To the point the original subcontractor that installed the unit refused to come back because they said it was costing them money each time they had to come repair the unit and add refrigerant. My response was that if you fix the problem you won't have to keep coming back. I finally was able to speak with someone at Sears Corporate office and the last company that was sent to repair the unit seemed to fix the numerous problems. The air conditioner unit has run fine up until last week when the unit was switched over from cool to heat. The unit stopped working again. The repairman was at the house this morning and said the valve has holes in it and it was supposed to have been replaced in August when the coils were replaced. This unit is just over a year old and repairs have been made and parts replaced about 8 times within the first year. This is mind boggling to me when this is supposed to be a brand new unit. The repairman temporarily fixed the problem until he can get back in a week to replace the valve. I'm not sure if I received a defective unit or if this is a common problem with the Sears Kenmore Heat Pump. With the money that I spent for this system, I believe that I'm entitled to a replacement (a unit that is problem free).