Electrolux Fridge / Freezer problem

[spik1947]

Hi Guys and Galls

I have a Electrolux Fridge/Freezer Model ER 7946B ( yes it is getting on a bit ) , and the problem it has , is that it not switching back on at the correct Temp , it is waiting untill the temp in the Fridge is getting on for 10c , I have ordered a Thermostat for it , but I think that only controls the Low temp it gets to that is set by the Temp Dial .

I thought the High temp it kicks in at , is pre-set !! , not sure how though , just someone told me that mabe giving duff info .

I don't want to bin it because when it is running it is ok , as soon has it starts up the evaporator plate in the fridge gets cold / freezes the droplets of water within seconds .

thanks for any help

spike

[Glenn Moore]

Hi Spike
These FF's use an Auto Defrost type thermostat, which have a Constant Cut In Temperature of approx +3 Degrees C. So the fridge Freezer runs down to temperature, and the thermostat cuts out. The thermostat sensor which is mounted on the Fridge evaporator plate needs to warm up and reach the temperature of +3 Degrees C which automatically ensures that the ice on the Fridge evaporator has melted and drained away before the thermostat re makes and starts the cooling process once again.

Some FF's use a small heater which is clipped onto the back of the Fridge evap plate which is energised when the thermostat cuts out to warm the evaporator up , to assist the defrosting of the plate. Once the thermostat reaches +3 Degrees C the heater cuts out and the cooling re starts.
Some systems do not use a heater but rely on warm ambient air entering the refrigerator when the door is opened to defrost the evap plate and then re start the cooling.

So if your system is only restarting once the temperature is at 10 Deg C I would just get a new Constant Cut In Auto defrost stat from your local fridge wholesaler

[spik1947]

Hi Glen

Thanks for your reply , yes I fully understand what you have said , but I am not sure as to where the sensor is conected to you mentioned !! , the thermostat I have has a sensor tube that goes into the top of the fridge and inside and behind the evaporator plate , are you saying that there will be another sensor behind there and if so where does it go from there ! .

cheers

spike

[Glenn Moore]

Hi Spike
The thermostat has a changeover contact inside, so the contacts will make to start the cooling when the temperatures high and when it reaches its cut out temperature the contacts break to stop the cooling , but the contact switches over and makes another contact to bring on the heater if one is fitted. The heater is a simple tube about 3mm in diameter and about 300mm long which has a wire connected at each end. So there is only one thermostat which can do both functions. Danfoss make a thermostat for these units which is known as a Kit No 3. Ranco and others also make stats to suit
Kr Glenn