Hotpoint MIstral FF72P – Fridge Problem

Hi,

I am having a problem with the fridge in my Mistral Fridge-Freezer.

The freezer is working ‘OK’ – i.e. the temperature is -22C
The fridge is not cooling correctly.

I did some research and had hoped it might just need a defrost. I let is defrost for 36 hours and then powered it back on. It ‘worked’ for about 24 hours. Then the fridge temperature increased again.

I then replaced the Evaporator Thermistor, but this doesn’t seem to have fixed the problem. The current situation is:

Freezer = -22C (good?)
Fridge = 5C (but target temp set to 3C)

The compressor and condenser fan seems to be running all the time but the fridge temperature just isn’t coming down to the target temperature.

However, if I set the target temp to 6C, the compressor cuts out (which I think it should if the fridge is already at 5C). If I set the target temp to 3C, it doesn’t seem to be able to reach that temperature.

I have ascertained the following:

1) The evaporator fan is working. I removed the evaporator thermistor and turned on the unit. The fan span and the ‘evaporator thermistor open circuit’ error code was displayed.
2) The evaporator thermistor is ‘working’. When powered on, the fridge temperature doesn’t start to drop until the freezer cools to about -15C.
3) If I ‘spoof’ the fridge door as being shut, by pressing in the ‘light switch’, cold air can be felt coming from vent on the side of the fridge lamp.
4) The freezer seems to be achieving -22C without any difficulty.
5) The condenser fan is working.
6) The lower compartment containing the condenser fan and condenser tubing is dust free.

I’m not too sure what to try next. Has anybody experienced this before?