FIXED WHB36S Whirlpool Mini Fridge Relay

[jimbo2]

Model Number

WHB36S

Brand

Whirlpool

Age

1-5 years

I'm trying to trouble shoot a Whirlpool WHB36S mini fridge that's stopped working. It makes a clicking noise and the compressor doesn't turn on. I took out the starter relay and it failed the rattle test. Tested it for continuity as well with my multimeter and it failed that as well.

Now the difficult part has been sourcing the right relay. The original is part number JPQII-4.7. It's a 4.7 2 pin relay with pins in position 1 and 2.

I tried these MZ92 4.7 with pins in positions 1 and 4 and the fridge still won't cool. Oddly enough with the replacement relay, the digital temperature display says the temperature is dropping, but the my laser thermometer was showing room temp and the compressor got very hot. amazon.com/dp/B07MXBL4B6

Any ideas on a suitable replacement? Would a 4.7 3 pin work and just leave one pin unused? I can't seem to find the original relay anywhere.

 

[Jake]

WHB36S does not pull up as good.

Read it from the model number tag on the machine.

Jake

 

[jimbo2]

Thanks Jake. I’m reading that off of the tag on the back

 

[Jake]

That's very odd, I can't pull up a parts list or nothing on it.

I can ask Rick.

Jake

 

[jimbo2]

I believe it’s a unit made overseas that Whirlpool slaps their name on. Target sells them.

 

[wobiii]

Can you post a pic of the relay you took off of it. Using the words "pin 4"has me curious.

 

[jimbo2]

The relay has numbers at each corner. The one that came off the unit (pictured) has pins in the positions labeled “2” and “1.” The replacements from Amazon have their pins on opposite sides of each other with the “hump” in between them. Not sure if that matters at all though.

 

[rickgburton]

Here's the part you need:

Whirlpool 4387913 Relay & Overload Kit (AP3108669) - AppliancePartsPros.com

Relay & overload kit 4387913 / AP3108669 made by Whirlpool

click.linksynergy.com

 

[jimbo2]

Thanks. It will be ok to leave 2 of the prongs open?

 

[rickgburton]

I'll try to explain it to you. There's only two wires that supply 120 VAC to the compressor. One wire connects to the overload which is connected to the compressor common pin. The other wire is connected to the relay terminal over the compressor run pin.

The two terminals on the relay on the right side are connected together and the two relay terminals on the left side are connected together. If you could see the inside of the relay it would look like this:

So when power is supplied to the overload and relay, both the start windings and run windings are energized. When the self-heating solid state relay has reached temperature it will change from low resistance 3-12 ohms to high resistance 10k-20k ohms and switches off the start windings. As you can see the relay only needs the one terminal. The other three terminals on the relay are for capacitors. A run capacitor is connected across the run windings and start windings. A run capacitor isn't necessary for the compressor to run properly. A start capacitor is connected inline with the start windings. Your machine doesn't use a start capacitor because the compressor is too small.

 

[jimbo2]

I'll try to explain it to you. There's only two wires that supply 120 VAC to the compressor. One wire connects to the overload which is connected to the compressor common pin. The other wire is connected to the relay terminal over the compressor run pin.
View attachment 63493

The two terminals on the relay on the right side are connected together and the two relay terminals on the left side are connected together. If you could see the inside of the relay it would look like this:
View attachment 63494
So when power is supplied to the overload and relay, both the start windings and run windings are energized. When the self-heating solid state relay has reached temperature it will change from low resistance 3-12 ohms to high resistance 10k-20k ohms and switches off the start windings. As you can see the relay only needs the one terminal. The other three terminals on the relay are for capacitors. A run capacitor is connected across the run windings and start windings. A run capacitor isn't necessary for the compressor to run properly. A start capacitor is connected inline with the start windings. Your machine doesn't use a start capacitor because the compressor is too small.

Thanks Rick, this is helpful. This one has a total of 3 wires though. Red goes to the overload and then there’s a white and black each going to a terminal on the relay. Here’s a photo I took of the original relay and overload.

 

[rickgburton]

Your picture is too close. Looks like spaghetti LOL. Do you have a run capacitor? Do you know what wires were connected to the relay and where they were connected?

 

[jimbo2]

Your picture is too close. Looks like spaghetti LOL. Do you have a run capacitor? Do you know what wires were connected to the relay and where they were connected?

My bad! Here’s a marked up version. This is a side angle of the relay and overload. Compressor is just out of shot on the right.

White wire goes to first relay terminal (labeled as white 1 on photo and unplugged in photo). Black wire is connected to the second relay terminal below (green 2 on photo). The red wire goes to the overload (labeled red 3 on drawing).

I do not see a capacitor. Just the relay and overload. I also included a more zoomed out photo.

Thanks again for the help so far. I really appreciate it!

 

[rickgburton]

I can't see where the wires are coming from but I must be missing something. Are you saying if you put the wires on the new relay the same as they were on the old relay, it doesn't work?

 

[jimbo2]

I can't see where the wires are coming from but I must be missing something. Are you saying if you put the wires on the new relay the same as they were on the old relay, it doesn't work?

Correct, but the terminal layout of the new one is slightly different which could be my issue perhaps. They’re both two terminal 4.7 ohm relays, but the original had both pins on the same side. Whereas the replacement one has the two pins on opposite sides.

I haven’t been able to find a 2 pin relay with an identical layout to the original.

 

[rickgburton]

Oh crap! All that explaining and you didn't get it. I think I was too technical, my bad. The relay in my part link has 4 terminals. The one in your pic has 2.

 

[jimbo2]

Correct, the part that came with the fridge only has 2 terminals. So would the 4 terminal relay in your link work in this instance?

 

[rickgburton]

Yes, put the wires on the same terminals.

 

[jimbo2]

Still no luck. This part tripped the breaker after being connected in an identical fashion to the original. I called the Galanz parts department (they do the private labeling for Whirlpol) and they (and apparently nobody else) do not carry the original JPQII-4.7 relay. Gotta love it.

 

[rickgburton]

Measure the compressor windings. Measure from each compressor pin to ground.