I have a customer who has a Coleman Model BRHQ0361BB heat pump that wasn't defrosting. I jumped out sensor (it was about 55 od temp)and tried to force into defrost but it wouldn't go. Made a clicking sound like trying to switch, cut out fan for a second or two then back on. I jumped into ac with r to o and it switched fine. On further attempts to jump into defrost nothing happened. Replaced board (ICM303) and sensor and it makes same clicking noise every time i try to jump into defrost. About 40 od temp. Just a little history: I replaced transformer(40va) and capacitor outside during the summer. Dog had chewed thru tstat wire. This is in a mobile home.
Thanks for any help