Isotherm GE80 fridge kit gone faulty.

[popeye the sailorman]

Hi all.
So over the weekend after 15 years of faultless service it has stopped cooling.
However the cooling fan activates when the thermostat in the box is switched on.
The cooling fan goes through this cycle of coming on and running for about twenty seconds or so then shuts down, as it stops the compressor seems to shudder momentarily.
The compressor is definitely not running as I know what it sounds like when it is functioning correctly.
My first thoughts are has it overheated with the high air temperatures we have had over the weekend.
Not had real opportunity to investigate due to having to leave the boat.
All I know is there must be 12v supply as the cooling fan works.
Has anyone got an comments on how to proceed with fault finding.
All replies greatly received, thanks in advance.

 

[MattS]

Have you checked the voltage of the power supply to the compressor?

I had similar symptoms to this (fan would run but compressor not) when the wiring to the fridge was too old and dropping too much voltage.

Best way to be confident this isn’t the problem is to put a multimeter on the +ve and -ve power supply at the fridge end, and turn the fridge on.

You’re looking for the voltage readying at the fridge when it’s trying to run (and drawing current).

Dropped voltage is such a common issue with these 12v fridges it’s worth ruling it out!

 

[popeye the sailorman]

Hi MattS.
Many thanks for your interest and reply.
Yesterday I connected the power from a fully charged 12v battery, with the engine running cable length less than 2 metres. No change, disconnected the cooling fan. No change, bypassed the thermostat with a link. No change.
Put a LED on the diagnostic of the controller and got the three flash error code.
Danfoss say it's the compressor rotor blocked or over pressure in the system.
Trawling the internet suggests reducing the pressure in small amounts.
It has stood for a week so thought the pressure would equalised already. Or the controller is the fault.
Mulling options over at the moment.