Zanussi ZNB 4051S Fridge Freezer Stopped Working?

Hi,

My Zanussi ZNB 4051S frost free fridge-freezer stopped cooling in the dridge compartment. I called out an Engineer who said it simply needed defrosting as the ducts/vents from the freezer had become blocked and so cool air wasn't getting to the fridge.

After defrosting for 48 hours during warm weather and switching back on for 24 hours I still had the same problem.

Two days later the temperature in the freezer started to rise very quickly. I've now switched the appliance off.

There was a slight frost build up on the freezer when the Engineer first came to take a look.

There is just one motor compressor on this appliance.

Any suggestions please before I spend another potentially wasted call-out fee?

Thanks,

Paul