Refrigerator Problem Repair: How To Fix A Refrigerator Temperature Control

Do-it-yourself guide to troubleshooting and replacement of a refrigerator or freezer temperature control switch.

Before replacing the refrigerator's temperature controls, you should do some basic troubleshooting to make sure the problem stems from a defective control and not some other problem. The most obvious thing to check is that the refrigerator is plugged in and receiving power from the outlet. If it is running, but not cooling, it could be due to dirty condenser coils or a defective door seal. Once the coils are clean and the door seal has been checked, you can be pretty confident that the problem is the temperature controls.

There are usually two control knobs, one that controls the temperature of the freezer and one that controls the refrigerator. Although they appear to be independent controls, it is important to understand that the cold air comes solely from the freezer area into the refrigerator compartment. The freezer control determines how much cold air the condenser produces while the refrigerator control adjusts the flow of cold air from the freezer to the refrigerator compartment. If there is no cold air on either side, it is probably the freezer control that is at fault. The procedure to replace the control switch is the same for the refrigerator control and for the freezer control.

Even though we have gone through this troubleshooting, it is still a good idea to test the control mechanism before replacing it. You will need a multitester and possibly needle-nose pliers and a screwdriver for the testing. First, unplug the refrigerator so you don't get shocked. Then, remove the temperature control's dial and/or housing. The dial will just pull straight off, but the housing may have screws holding it in place. After removing the housing, just let it hang by its wires. There should be two wires attached to the control. Label them before disconnecting so it is easier to put back together. Remove the wires by pulling on the slip-on connectors, not the wires themselves. Needle-nose pliers may be needed to remove these connectors from the terminals, especially if the refrigerator is old.

Set the ohms setting on your multitester to X1 and attach one probe to each terminal. Turn the temperature control to off or to the warmest setting if there is no off position. The multitester should give you a reading of infinity if the control is on off and a reading of near infinity if there is no off position. Then turn the control to the coldest setting and retest. Now, the multitester should give you a reading of zero. If both of these tests are not passed, the control needs to be replaced.

You already have the dial part of the temperature control disassembled, but there is also a temperature probe attached to it. Remove all fasteners holding on the existing probe and take note of the path of the probe. Install the new temperature probe along the same path as the original. Do not bend at a sharp angle and try to avoid bending more than necessary so the probe does not get damaged. Attach the refrigerator's wires to the new temperature, replacing the connectors if corroded. Replace the switch and any necessary housing screws you removed earlier. Plug in the refrigerator and set the temperature control to the midpoint setting. The refrigerator should start cooling down within one to two hours.

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