WH and nothing else big (microwave or A/C) will be OK on 15A.
But, northmec is right, propane would be a safer choice.
No fan on the A/C is not a function of your power limits. You have a problem that needs looking into. Breaker, wires, thermostat, etc.
TT 2015 19RD "TheJayco"
TV 2003 F-350 "Montblanc" - Housebroken chore truck
Sitting in The Cheap Seats.
And proud of it!