I have an isotherm
Asu 4701 unit that came with a boat
that is new to me. The unit was run with the water
intake closed for a period. I charged the coolant
and The system will run and cools well but I can not get the pump
and the compressor
to run at the same time. If I turn on the unit the compressor
runs, but the pump
does not and eventually the system shuts down giving an error showing the pump is not functioning. As it should. If I run a separate 12v power supply to the pump and bypass the system the pump runs fine and the unit cools like a champ. The issue with this is the pump runs full blast, all the time, and is very loud. Not a permanent solution.
I have bypassed the asu unit and put a jumper on the black power box to bypass the thermostat, put the 12v power connections directly on the black box as well and the compressor runs, but with the water pump
connections directly to the black box the pump still does not run.
I swapped out the voltage reducer and am getting the same result. I get 12v from my electrical system
&12v coming out of the power connections on the black box. So I think I am good there. When I put 12v into the voltage reducer I get about 7 amps on the positive terminal coming out, #5, and nothing on #6, the ground. There appears to be no return path. The voltage reducer is molded shut so I can't take a look at what's inside, and obviously there are no specs available.
Looking for some input.