Hi my Scandinava frost free Fridge model no Sff6745 serial no 23619448 the defrost termination thermostat no longer works and is no longer available.iwould like to install a digital temperature controller but I don't know how to wire it up can please show me how to wire it so the defrost heater comes on . please show me were which wires I take from the main thermostat and which wires I take from the defrost heater and fan .any help would be greatly appreciated.regard
This might provide some avenues to explore.
https://www.how-to-repair.com/faqs/scandinova-sff6745-fridge-freezer-defrost-thermostat-thermal-fuse-not-working/