I have two fridges of the same model, DFF280WDB from Danby. One black unit works fine, and serves as a reference. The white unit, once plugged in, doesn’t make any noise, interior lights are flashing slowly. Compressor doesn’t start, doesn’t click.
Already tried: I swapped the boards, and the “white” controller board works fine in the “black” fridge, so I believe that rules out the board as the source of the problem.
I also removed two parts that were connected to the compressor, likely the overload protector and what is marked as a relay. The overload protector has continuity.
The other part should be the relay, with “M” and S” markings (S for starter coil, not directly connected to AC, M for motor, directly conncted to AC?). It contains a disc, though not sure what purpose it serves.
Could it be something in the relay box next to the compressor? How do I test this part?
Edit: nevermind, I found out it must be a PTC, with resistance between terminals increasing as current flows. From what I understand, when cold, AC is applied to both starter and main compressor coils, running capacitor is shorted, then power is gradually cut off from the starter coil, and capacitor is un-shorted.
The PTC part tests at 5.3 ohms, whereas the OL tests at 0.6 ohms. Does that mean the start relay isn’t good anymore?
Could I try to hook up the compressor directly to the AC, first hooking up M and S to phase, then disconnecting S after one minute, leaving only M connected to phase?
Source: New feed