A couple of items....
I see you are wintering in Port St Lucie Fl, where the humidity varies from 65-98 %, and dew point runs high 70s too.
a. High humidity like that with high dew points tend to sometimes favor early icing in the condenser coils..which really shuts down heat pump's heat extraction from the outside ambient air. If your condensing coils have not been cleaned in a while..icing occurs in the coil earlier in lower temp-high humidity, high dew point scenarios...especially as night falls and into the early morning. Suggestion, with the unit not operating...get some Simple Green and a small hand sprayer. Dilute the SG about 3oz to ten oz water. Starting at the top of the coils..gently spray SG solution so it travels at least 3-4 inches into the coil banks. Work your spray across the coils eventually all the way to the bottom. Wait 15 minutes. Take your water hose and very gently, rinse the coils clean starting at the top and flushing all to the bottom. Try the heat pump again when it's a 65-70 degrees and lower humidity (50%) and dew point. Watch the coils to see if any icing occurs.
b. Check that both compressors come on line during Heat Pump demand temp. # 1 compressor should start within 15 secs and be indicated at the power panel by about 12-14 amp draw. About 30 secs later # 2 compressor should start and the power panel should indicate 22-24 amps.
c. Have you checked your AC current input to the coach at your park. Usually heavy (park & neighbors) A/C and Heat Pump ops will really suck down the incoming voltage (108-105V) to your rig too and this really cripples the Heat Pump start up cycle. You should always have 120 +- 10 Volts.
Quote from Unit Manual:HEAT PUMP OPERATION (HEAT MODE)
1. Begins with a call from the thermostat, 12 volt positive (+) to terminal #8 (W) in the 9-pin connector. (White with Black stripe
wire at the thermostat). The Ground (-) is Blue in terminal #4.
2. The p.c. board takes over at this time and controls all functions of the heat pump.
3. 115 VAC should appear between the T18 and T19 Rev Valve Out terminals.
4. This voltage continues to the reversing valve solenoid coils and switches both reversing valves to the heat position.
The way the reversing valves work is the solenoid valves open pressure ports to operate a nylon slider in the cylinders. This sleeve can jam or bind half way (called "wind milling") and will over heat the compressor in a few minutes. Once this happens there is little chance that the valve will work again.
d. Have you checked your A/C unit air filter lately. Change it...Is there something (suitcase, case of beer, paper bag etc) blocking/restricting the inside air intake of the A/C unit.
Keep us updated.
Charlie