Had my side by side cause problems and have been reading these threads. First thing the fridge got warm and investigated that freezer was frosted and blocking air flow and froze the vent at the top.
Defrosted freezer and now it trips the rcd when switched on.
Took panel of inside and disconnected defrost heater and it switched on.
Tested heater with multi meter but is has continuity so the problem must be elsewhere on the circuit but where?? any ideas appreciated.
You have an earth leakage fault on the defrost heater. You will still get continuity with a meter. You need a megger/insulation tester to test it properly. But if it works and doesn’t trip when you have disconnected it then that answers your question.