Upon arrival customer stated that heat stopped working last night. Stated that it has been running fine u til we reached the colder temperatures. After inspection of 7 year old heat pump system found that system had a bad defrost board. When I tried to manually the board into defrost mode it would not go into defrost. It would just turn off the outdoor system. Outdoor capacitor is testing bad, outdoor contactor was very pitted. Blower wheel was clean, evaporator coil is clean, blower motor capacitor tested good with no issues. Drain line inside p trap was a little clogged, drain line does not have enough elevation to drain properly. There is no in line flood protection on system, unit does have a float switch in drain pan. Recommended new defrost board, outdoor capacitor, outdoor contactor, wet pan switch, in line float switch, drain line elevation, customer only wanted to have defrost board and capacitor installed at this time. Will order board and follow up with customer tomorrow for