fridge freezers not cycling on and off - please help!!

[paddy_irish]

I have recently been experiencing fridge freezers with mechanical vt9 thermostats not ever cycling on and off, I have tried changing the thermostats on them but it doesn't make any difference at all, they just stay on all the time! Also I have changed the compressor thinking that was the problem but it just never works! Any help with this would be appreciated as its becoming a common fault for me

[paddy_irish]

anyone??? Im really stuck here!

[joe-ice]

Dont usually work on domestics but it could be possible that the tstat is controlling a relay that is stuck closed,also if from what i understand it they are frost free fridges i dont think a vt9 is suitable as the cutout is too low ,need a vxo on these -15 as opposed to -26 cutout.Dont think the feeler is in direct contact with the coil on the frost free cases

[TERRENAS]

Some times what causes that, is a gas leak (undercharge), the probe of thermostat never reaches the cutout temp because saturated liquid never reaches on to it.

[paddy_irish]

It's def reaching the cut-out point, the fridge is at -10 and freezer is at -40, also its not a frost free system they are both just regular fridge freezers, basically a thermostat and a compressor, ill try the relay on the compressor and get back to you. thanks for the help

[paddy_irish]

think they were low on gas, put a charge in each and they cut out, just waiting on them coming back on now