Bimetal Defrost Thermostat WP10442411

The frig was hot but the freezer was cold. I opened the back of the freezer and found the condenser all frozen over. Upon inspecting the defrost thermostat I found that it was split open, as if water got into it and the froze breaking it open. I used a blow dryer to defrost the condenser. I then spent a long time trying to find the model on-line, even the manufactor said it did not exist. Partselect.com was the only place that said the model did exist. When that part came in I toke the back of the freezer out again. Unplugged the defrost thermostat plugged the new one in clipped it back on the condenser and put the it all back together. Everything is working fine now.

Mine is a top refrigerator and bottom freezer. Whenever working with electrical applicances always disconnect the electrical power before beginning work on it. Never try to force anything. If there is abnormal resistance, use logic and determine if there is an obstable that needs to be dealt with. Loosen all screws halfway then take them off completely. Replace all screws part way and begin by inserting and starting the screws by hand then use the nut dreiver and last tighten until snug. Also, be ware that wires can get brittle and may break so handle them with care. The wires and other parts may have been frozen and defrosted many times over the life of the refrigerator. Have a flash light or other light source so you see everything well. The light will be off because you disconnected the electrical cord.

First check the defrost timer. On my unit it is located in the bottom front corner behind the removable ventilation grill. Remove about 4 hex screws. Its most useful to use a nut driver (looks like a screw driver but the tip fits different hex screws. To check the defrost timer you can turn the orange/red knob to the right and see if you can advance the timet to turn on the defrost cycle. If this works then the problem is not the defrost timer. I changed my defrost time anyway not that it was broken.

To replace the defrost thermostat, remove the food and shelves from the freezer. Use the hex nut driver and remove the hex screws from the back panel of the freezer section. If needed you will need to remove the ice maker. I don't have an ice maker. Once the back panel is removed you will see some coils, wires and other parts. Disconnect the two wires for the defrost thermostat, you can identify the defrost timer because you purchased one on-line. Carefully remove the defrost thermostat which is attached by a tension clip. The ends of the wires (terminals) may not be the same style. If needed cut the wire terminal plus two inches of excess wire from the old defrost thermostat and splice it to the new defrost thermostat. If you have a soldering iron, solder it, if not use a wire nut and electrical tape or just twist the wires together and cover with two layers of electrical tape. Now, attach the wire terminals of the new defrost thermostat to the wires that you disconnect earlier. You can not mix them up because the ends are different. Pull the tension clip slightly apart and slip onto the tubing where it came off of originally. Replace the back cover and air grill and fasten the hex screws. Attach the ice maker if you have one. Replace the shelves and food and close the freezer door. Plug in the refrigerator. It may not go on immediately. If this is the case, go to the defrost timer and turn the orange/red knob to the right and you will cycle the defrost timer to activate the freezer. Let the refrigerator run for a while, even a few hours is okay, and then it will hopefully go into the normal automatic cycle.

Other parts that may go bad and need replacing are the condenser fan that you will find by removing the cover in the back of the refrigerator. This fan runs when the refrigerator is on to cool the compressor. Also a heater coil is used to defrost the freezer. Infrequently, this part goes bad.

There is no separate cooling unit for the refrigerator compartment of the refrigerator. The cold air for both the refrigerator compartment and freezer compartment originate from the freezer. The temperature dial in the refrigerator compartment regulates the amount of cold air from the freezer that will circulate to the refrigerator.
(This just give you a clue that if the refrigerator compartment is warm the problem will still concern the freezer.)

Also, please clean off the coils that are covered with dust and webs.

This is a brief summary and depending on your level of experience and general logic and problem solving skills. This repair may or may not be easily understood. One last tip,

I removed the shelves from the freezer. I unscrewed 6 screws with a 1/4" nut driver and removed the back panel. The coil was solid ice because the defrost cycle wasn't working. I thawed the ice with a hairdryer (5 minutes), unplugged the thermostat and installed the new one (it simply clipped on to the coils), and reassembled the back panel and installed the shelves. Total time, about 14 minutes. Total cost, less than $20.00. I can't even get an appliance repairman to show up at my door for less than $100.00! Thanks to your website, I was able to diagnose my problem, order the correct part and fix it myself! (I bookmarked your site under my favorites). Thanks for this great consumer service. It's easy, inexpensive and quick to do it yourself!

This is a bottom freezer refrigerator. First I unplugged the refrigerator. I then removed the wire shelf and wire tray from the freezer. I then removed the ice maker be removing the three screws that hold it in place. I then disconnected the icemaker electrical connector. I then removed the 7 screws that hold the panel at the back of the freezer revealing the evaporator and heat exchanger. I then unclipped the icemaker wiring harness from the panel. The whole evaporator/heat exchanger was buried in ice. I defrosted it with a hairdryer. This took about half an hour. The bi-metal thermostat is attached to the heat exchanger by a clip. Be sure to wear latex gloves to prevent cutting your fingers on the aluminum fins. I disconnected the electrical connectors and then carefully unclipped the thermostat. I discovered that the new thermostat had spade connectors where as the original had one spade connector and a bullet connector on the brown wire. I reused the original bullet connector by cutting it off the old thermostat and splicing it onto the new thermostat. I reversed the process for reassembly. There is no longer any ice build up and the refrigerator is working normally.

There is already a lot of good advice on this web site and others on how to diagnose and do this repair. I'll add a few additional comments that might be helpful.

I wanted to confirm that my old thermostat was in fact bad. I did this by disconnecting the two connectors and connecting them to each other to bypass the thermostat. This is like having the thermostat always closed. With the back panel still open so I could see the frozen coils I plugged the fridge back in and turned the defrost timer knob with a screwdriver to get to a defrost cycle. I could then see the heater element slowly melting the ice. This is of course not a safe way to operate the fridge. Over time this would get too hot and damage the food or worse. I only did this for a few minutes to see the system operating. I did not melt all the ice at that time. Also, it is of course dangerous to plug the fridge in with the panel open, so a great deal of caution is advised.

When I got my new thermostat I wanted to confirm that it worked before going through the install procedure. To do this I cooled it down and then used an ohm-meter to see that the circuit was closed. The important thing I found out is that ice-water, even 2 parts ice, one part cold water, was not cold enough to do this. Only when I put the thermostat into a cold freezer for a while did it get cold enough to close the circuit. I did this side by side with my old thermostat and saw that it was in face bad -it never closed the circuit.

This part from Part Select was an exact match for this freezer-on-bottom Whirlpool refrigerator. The connectors were identical so I did not have to solder wires together as others have need to do.

Some people get the ice off of the coils with a hair dryer. For me this could take half an hour. What worked better and much faster was spraying warm water on the ice with an old spray bottle. This adds extra water to the mix, but it did not overflow the drain pan. Even if it did, it would be easily mopped up if you can roll the fridge out.

One last thing. I suspect this thermostat broke in the winter, but with the dry air the fridge worked for a long time. Once summer hit and the house got humid, the coils iced up quickly.

Good Luck!

First I had to determine what was wrong. Obviously the compressor was working since the freezer was cold. Digging for awhile revealed that the evaporator coils for the freezer had frozen up into a solid block of ice. Then I had to figure out why. Tested the defrost heater in place--small resistance (~3 ohms), OK. Removed and tested the timer--unsure. Removed and tested the defrost thermostat--did not turn on when plunged in ice water or frozen with canned air (turn the can upside down--be careful!, you can instantly freeze-burn your skin), bad. Chose to purchase and replace both the timer and the thermostat. Took the opportunity to THOROUGHLY clean everything, front, back, and underneath. Found the drip tray transition piping cracked at the junction and replaced it with a cut-off funnel "glued" into place and to the underside piping with the RTV Silicone. When parts arrived, tested them and confirmed that the original timer was OK and the thermostat was bad. Installed the new thermostat (and went ahead and installed the new timer). NOTE: one connector on the thermostat was not identical to the orginal equipment. Rather than cut the refrig wiring, I chose to build a jumper with the original connector on one end and a new one for the new thermostat on the other. Buttoned everything back up, re-leveled it, and let it run for 24 hours at the manufacturer's recommended "first" settings (4 and 4) without being disturbed. Seemed fine, loaded it with food, everything is great including non-frozen veggies! (I suspect the ice was forming frequently and blocking the return from the refrig compartment, which is right next to the veggie drawer.)

Had to remove screws inside back of freezer panel, took off old thermostat. This one had a different plug on the end that wasn't compatible, so had to cut that off and wire it to the old plug end. Piece of cake. Put back panel back on and back in business. Hardest thing was getting the screws out!

I removed the Icemaker then the backpanel in the freezer. The fan motor removal required only to hex screws and three wires to dismount. The biggest problem I had was the replacement motor had the connecting pins for the wire harness on the reverse side. I thought I could unbolt the motor and flip it but this did not work. I remounted the new motor and was able to get the wires connected. The thermostat clipped in place but one of the wires had a different connector than the new unit. I used a wiring snap connector to complete the connection. The defroster timer was under the refridgerator and after taking two screws off the cover plate was just an unplug and plug in the new unit. When I first turn the unit back on nothing happend. I soon realized I had to advance the timer until the unit kick on. It has worked fine since and solve both the noise problem and defrost issue.

Research on the internet showed the problem was either the defrost thermostat or the defrost timer. I decided to replace both.

1. Emptied the freezer into an ice chest

2. Removed shelves, some of which were held in with screws.

3. Removed freezer back panel.

4. Replaced freezer thermostat, very simple, one clip and two wires.

5 Replaced all removed parts. Put food back in freezer

6. Removed and replaced defrost timer from underneath front of fridge, screws were awkward to reach.

7 No more heat around outside of freezer

I removed the panel in the back of the freezer and found the evaporator to be a complete block of ice. I defrosted it with a hairdryer. Following advice from the Partselect web site, I measured the resistance through the defrost heater. It was about 30 ohms, so I decided that it was OK. Next, I advanced the defrost timer manually with the compressor on until it turned off. The defrost heater did not operate. I concluded that the problem was the defrost thermostat. After installing it, the freezer worked properly.