FIXED 1939 GM Frigidaire cold wall refrigerator not starting

[Sean Duffy]

Model Number

unkown

I have a 1939 frigidaire cold wall and I need some help.

I have used the fridge for many years with no problems. Then about a week ago it just quit with no warning.

I looked at the wiring and it was all in very bad condition. The insulation was simply coming off. I took some "before" pictures and It still had the wiring diagram on the back. using the diagram I rewired it. In this process i found a wire broke off the start capacitor. I replaced the start capacitor. I have the exact same problem as before. I have checked my work again and again.

I got into the relay and if I close the switch with a test lead or screw drive the start relay pulls in for second and the compressor starts. But when I let go of the contact it open and the compressor stops.

I closed the switch indicated by the orange arrow.


Any help is greatly appreciated.

 

[rickgburton]

Can you give me a better picture of the wiring diagram?

 

[Sean Duffy]

Is this better?

 

[rickgburton]

No, sorry to be a pain. You cut off the ledger a the bottom. I'm old. What can I say....lol

 

[Sean Duffy]

No worries. Let's try this one.

 

[Sean Duffy]

I used a green wire in place of red. Much easier to find.

 

[rickgburton]

OK, that one works. Give me a few to look it over. It's probably going to be the relay itself that's bad. Try cleaning the contacts with a fine grit sandpaper or a wire brush. Be careful moving the wires they're probably brittle and the wire casing will fall off. Replacing wires is a can of worms better left unopened.

 

[Sean Duffy]

I have already rewired every thing except the light and switch.

What makes the switch in the relay pull in and stay in? If I push it in with a test lead or use a jumper wire, the compressor will run and the fridge will cool. (The one the orange arrow is pointing to in my original post.)(last pic)

 

[rickgburton]

OK, you need to transfer these wire locations:

To this side of the relay:

Maybe this will help. Hotwire relays operate on the theory that electrical energy can be turned into heat energy and that, when the temperature of a metal is increased, the metal expands. Hotwire relays operate the start winding circuit. In addition, the hotwire/thermal relay controls the run winding circuit, if for any reason the circuit draws excessive current. The device consists of a specially calibrated wire made from a material with high oxidation resistance and two sets of contacts. The contacts are controlled by the hot wire, either through the use of heat-absorbing bi-metal strips, or by its expansion of the hot wire, depending on the design of the relay.

 

[Sean Duffy]

Rick, So are we still thinking it's a relay problem? If so what relay would you recommend? I do not know the HP of the compressor motor. I have looked. It's not marked.

And thanks again for your help.

 

[rickgburton]

I believe these two contacts supply the voltage for the hotwire/bi-metal.

I think the relay is probably bad. The fact you can start the compressor pushing the contacts together indicates there's voltage at the hotwire and the hotwire is not working. However, I've been wrong before. There's like 4 or 5 different styles and they all work a little different. For the start windings to be energized, there needs to be 120 VAC across the black wire and the red wire. It's the current in that circuit that operates the hotwire. Whatever contacts close inside the relay should energize the start windings. That's the two contacts I marked. You check it and see what you think. The compressor is probably a 1/4 hp. Sometimes it's on the model tag or a tag on the frame by the compressor. That relay is going to be hard to find. You can check eBay and Amazon. Or you van use a 3-IN-1 hard start. It replaces the relay/overload/start cap with a solid state device.

I enhanced the wiring diagram to make it easier for me to see. I think they call it OCD ......LOL

 

[Sean Duffy]

There is no voltage between the terminals you marked. There is however 120 VAC when checked between the terminal I marked red and the two terminals I marked blue.

I hope this helps.

 

[rickgburton]

Are either of those two points connected to the hotwire? I don't know what those translate to unless you transfer them to the other side of the relay so I can see what they are connected to.

 

[Sean Duffy]

Are either of those two points connected to the hotwire? I don't know what those translate to unless you transfer them to the other side of the relay so I can see what they are connected to.

Ok. I understand. I will take some time tonight to see if I can do that. Thanks again for all your time Rick.

 

[rickgburton]

No problem my friend! happy to help

 

[Sean Duffy]

I think I may have found the problem.
The little coilie wire is not attached at the end on the spring steel.

 

[rickgburton]

I think you nailed it What terminal is it?

 

[Sean Duffy]

It's the red wire from the cold control.

 

[rickgburton]

I think that connection is "silver" soldered (brazed). Not sure.

 

[rickgburton]

That wire is actually what they used for the overload. That means the relay contacts should be ok.