Dometic / Cruisair issue

[Constellation1]

Interesting problem with one of my Cruisair AC / heat pumps. the water pump doesn't turn on in heat mode. Everything works as it should in AC mode. However in heat mode the pump doesn't come on and then I get a low water flow Hi / PS error.

Any ideas?

 

[Turtle Blues]

If it is moving the reversing valve but not powering the pump the first dockspert guess would be check the control board.
Do you know what one you have?

 

[Arc]

The command from the control head goes to the controller. When you asked for heat it looks at voltage in, temp, hi amp draw. If everything is a go it tells the pump to turn on. Then if it sees water pressure it positions the reversing valve and turns on the compressor. If it sees anything fail it shuts down and throws a code. You unit may look to position the valve first before turning on the pump . If so may be a stuck valve

 

[draakken]

if the compressor is coming on, you might be able to use thermal imagery to look at the reversing valve to see what the flow of refrigerant is, and then compare it to the flow in cooling mode.

 

[SailorGreg]

Interesting problem with one of my Cruisair AC / heat pumps. the water pump doesn't turn on in heat mode. Everything works as it should in AC mode. However in heat mode the pump doesn't come on and then I get a low water flow Hi / PS error.



Any ideas?

Often the blade terminals get corroded and break contact. A couple on the back of the unit and a couple inside the electronics box. Try re-seating them