Refrigerator Problem

boataholic

I have a Norcold DC-351D-F in the cockpit.  While waking my boat from its winter hibernation, I discovered that the fan was running on this unit with the thermostat turned off.  The only way the fan will turn off is if I turn the house battery off. The fridge compressor will not kick in even with the thermostat turned to max cool.  One more strange symptom; the last couple of trips out last year, the refrigerator started freezing everything in it.  This is odd.  I have owned the boat for 7 years and it has never done that.  Could just the thermostat be bad? This refrigerator is no longer in production and I have no doubt that I will not be able to find an exact size replacement.

boataholic

Did a little more looking at this refrigerator this weekend.  I have 12 volts going into and coming out of the thermostat, no matter where the dial is set.  Does this mean that the compressor is definitely locked up or could there be another electrical problem here.  How can I test? 

boataholic

I would guess that there is a module or board but it is not visible without taking something apart.  I am obviously not a refrigerator guy nor an electrician.  Just don't have many options in the boondocks of the Tennessee River! 

212rowboat

I doubt your compressor has anything to do with it.. it sounds like a control issue.. take your thermostat off and clean it.. I bet corrosion is bridging the points.

boataholic

Maybe I'm confused about how the thermostat works (entirely possible).  If it has voltage coming out, would it not be telling the compressor to kick in? I think you are probably 100% correct about the corrosion causing everything to freeze last year.  But the main problem this year is my refrigerator won't get cold at all.  In my pea brain, there is voltage coming out of the thermostat, the compressor should be running.

212rowboat

Ohhhhhhhhhh.... Disregard my last.. I thought you were saying the compressor was running non stop regardless of the thermostat...

Yup.. sounds like the compressor is likely frozen.. tap it.. turn it on and tap it at the same time... It may run fine the rest of the season, or it may still be toast and this just frees it up for the time being.

boataholic

Thank you guys for the valuable input.  Based on that, I will do a little more snooping this weekend.

boataholic

OK.......Beautiful weekend in TN! There are 5 wires coming out of the transformer.  2 tan wires have battery voltage, 1 pink wire has battery voltage, and 2 blue wires are dead.  The blue wires go through a connector directly to the compressor. Should I assume that the transformer is bad and replace it, or is there something else I should check.  The transformer is "humming" when the power is on. 

Dream_Inn

I'm also in vote for the transformer replacement.