hi, im gsr and i dont usually work on breakdowns so need some help! a fuse in the pcb (T 2a) blows every time i switch the main supply on, ive checked all the connections and seem to be fine i think its the pcb or the transformer can ne 1 help?
You need to check the motor windings first, transformer would be a favourite but first thing:
With the power off disconnect pump and fan, check resistances across the motors, expect 80-150 ohns on both (gas valve is worth a check too).
If all give the expected readings, transformer would be favourite before pcb
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