Steb does it only freeze when set high but maintain a cold environment inside the fridge?
The reason I ask is that a few cabinets, some Kelvinator/Candy’s and Brandt’s in particular, don’t like being turned up much beyond what you say as they have stats tht can cope with Southern Italian ambient temperatures as well as Northern Europe as well and it may be that there’s not much wrong at all.
It is also likely that that cabinet, although I cannot access the spares stuff now to check for you, has a PCB control as a stat and they ain’t cheap. IIRC, the last time I bought one it was over £70, Brandt aren’t exactly reknowned for being cheap on the spares I’m afraid, so it may be worth considering just how much to spend on a machine of that age very carefully.
K.