O.T. refrigerator

Should be electrical schematic somewhere on refrig if your not familiar with motor leads. Relays can be found generic at any appliance repair place, they may need model & serial nr of the refrig or data on compressor plate.

The click you hear is the overload. It is a bi-metal that heats and opens the circuit when the current is too high for a given period. The fan runs slow as the compressor motor is failing to start and fast when the overload heats and has opened the circuit to the compressor motor.

You need both the run and the start windings in the circuit with common to start the compressor motor. Once the compressor motor starts running, the back EMF builds up in the windings and the current drops. When the relay current drops, it disconnects the start winding and the compressor motor continues to run on the run winding.

The only function of the relay is to bridge the compressor motor start winding to the run winding so both windings are available for starting and then disconnect the start winding when the compressor motor is running.

Typically when a relay fails, the start winding is not in the circuit and the compressor motor is trying to start on the run winding only, not going to happen, O/L heats and clicks open.

The O/L may be in the relay or it may be mounted separately on the motor compressor shell. If the relay is replaced, the O/L should be renewed also.

If you can't figure out how to safely hot wire the motor from my 2 posts please just take the old relay and O/L to any appliance vendor and buy new (check for starting capacitor also). Can't be more than $15 - $20. In the early 80's a box of a dozen relays and O/L's was $15 wholesale, sold for $3 - $4 each. If it doesn't work on the new parts, junk it.

Joe

Another alternative would be get another cord and crimp ends onto it attaching the hot to R and the neutral to C on the compressor then short R to S on the compressor and see if it starts.

One hot conductor to R. The other hot conductor to C. Momentarily touch S to R until the compressor motor runs. The motor will run until you unplug the hot wire. After stopping do not attempt to restart for about 20 minutes, allow the refrigerant pressure differential to equalize before restart.

Your compressor motor probably has post type terminals. Very hard to crimp connector satisfactory without damaging post. Can you use the existing short wires from the relay to the compressor motor for testing? Alligator clips will work ok on stranded wire or its terminal connectors but don't try using them on the compressor motor terminals, will surely arc and destroy the post. Better to cut those wires if you have to, use them for testing and splice them when done if necessary.

Joe

BTW that box type relay is generically called a "hot wire relay" as opposed to a solenoid or a magnetic relay.

Joe