First floor system: I found sequencer 1 stuck on and sequencer 2 stuck open. Replaced sequencers. Tested all elements. I replaced defrost control board for heat pump. Tested operation. Tested defrost cycle. Ambient: 47. Suction: 60. head pressure: 215. Checked temperature rise. 13. Found system is low on type 410A Freon!! Leak searched and found Freon leak at indoor coil! Large leak in middle of left side of coil. Suggestions: need to check on cost and availability of replacement coil for first floor air handler. Heat pump system is about 11 years old. Recommend replacing system.