Problem with my fridge freezer... Help!

[Ajm434]

I have a frost free fridge freezer zanussi (electrolux) znb323s. A week ago I discovered the fridge part was not cooling but the freezer part seemed fine.
I emptied the fridge and turned off to defrost. The top part of the freezer was heavily encased in ice (evaporate coils I think).
After perusing the web for advice I removed the the front vent, the back wall and dropped the coil panel to access the fan. The fan had obviously not been working for some time cos it was covered in ice. I defrosted the whole fridge for 2 days.
Turned it back on and the freezer part seems fine although v cold. The fridge seems not to be cooling again.
The compressor seems to be constantly running.
Current temps are fridge 12, freezer -25, ambient 16. I haven't got anything in the freezer yet.
Thermostat set on 1 (1-6 setting).
How is the fridge cooled? When I removed the evap panel I could not see how cold air gets to the fridge. There aren't any holes in the fridge so I am assuming the back panel should be cooled.
If the thermostat is u/s would the compressor still run?
Does the thermostat control any duct vv from freezer to fridge back panel?
I attempted to remove some of the insulation from the fridge rear but was worried about cutting anything under it so abandoned that.
Any suggestions please?

[install monkey]

there should be an evap plate within the back wall for the fridge- check for the drain hole - user manual that I looked at shows 2x drain hoses at the back of the unit. unplug ur freezer wait 3 minutes,plug it back in, the compressor should have a delayed start, if it starts immediately then indoor pcb faulty, check resistance of the sensors, don't know the rated values, but if all sensors are at room temp then they all should read the same

[Ajm434]

there should be an evap plate within the back wall for the fridge- check for the drain hole - user manual that I looked at shows 2x drain hoses at the back of the unit. unplug ur freezer wait 3 minutes,plug it back in, the compressor should have a delayed start, if it starts immediately then indoor pcb faulty, check resistance of the sensors, don't know the rated values, but if all sensors are at room temp then they all should read the same
The compressor did start straight away.
The only drains I can find are the two you mentioned, the condensate drains from the freezer and fridge compartments, two large bore pipes which I have proved clear.
Indoor pcb? Is that the printed circuit board inside the fridge? And which sensors pose.
Thanks for getting back to me.
Rgds, andy.

[install monkey]

checked a few other pics of fridge and looks like theres no display so no pcb or sensors, usually the freezer stat operates the compressor and the fridge stat operates a 3way valve near the compressor

[Ajm434]

checked a few other pics of fridge and looks like theres no display so no pcb or sensors, usually the freezer stat operates the compressor and the fridge stat operates a 3way valve near the compressor

There's only one stat in the fridge and doesn't appear to be a 3 way vv near comp.
I've got stat at max 6 and the temps are fridge 12, freezer -20.

[Ajm434]

Pse someone help me. I'm now gettin it in the neck from the wife!!!

[tb637]

Hi, if the fridge has no air vents from the freezer it must cool by icing up the back wall in the fridge,
thats why you have a drainage hole near the bottom of that wall when it defrosts itself.
If ice dosen't form on that wall then the fridge must be low on refrigerant and you would need an engineer.

tony

[Ajm434]

Hi tony
That' makes sense. It can't be ice blocking the evap tubes behind the fridge part cos I proper defrosted it.
So I spose that's why the comp is continually running cos it can't get the lower temp the thermistat is asking for?
Think it may be worth getting a new fridge.
How much would a recharge be?
Thanks
Andy