Ok if you have ice on the back panel then you will find there will be a lot more on the evaporator behind the back panel.
What you need to do is take out the shelf's inside the freezer and take off the back panel towards the bottom.
From there you will be able to see if the evaporator has got to much ice in there. If so then you will need to check the defrost heater which is wrapped around the evaporator with a multimeter and see if the heater is faulty. If so then it will need to be replaced.
Also while the panel is off you will see the fan. You need to check this out as well with your meter and if faulty then it will need to be replaced.
Check them out and see what you find.
I will try that and let you know. thank you.
I have looked behind the back panel of the freezer. There is no ice. I can't determine whether the fan is working as I don't have a multimeter.
The ice appears to be only behind the panel situated at the level of the second drawer from the bottom in the fridge. The plastic water? filled container attached to the back of the fridge was also frozen.
Are the fans at the back of the freezer and at the bottom of the fridge on the left hand wall supposed to be on when the fridge/freezer is on or do they switch on and off as needed? When I switched the fridge/freezer on for a couple of minutes neither fan appeared to switch on.
Do you know why the ice builds up in the first place?
Thank you very much.