[Jack Houpe]

I have been working on our coach with a vengeance there are many things wrong with it but we had 27 degrees last night and my heat pumps will not kick on which is on the list of repairs, so I turned on the aquahot which got hot and turned on the thermostats and all the fans came on but only heat in the galley register and my water tank is warm, the bathroom bedroom and closet has no heat. I unplugged all three relays and installed one relay at a time and all three pumps come on, I banged on the check valves as I've read and then took this thermo image of the pumps in operation, shows hot water is past the check valve but not returning on 2 pumps. Could there be an air lock?