How to Wire a Thermostat in a Refrigerator
A refrigerator is a complex appliance with many vital functions that all work together to keep food fresh and cool. The thermostat is an essential component of this complex system that makes sure your freezer and fridge are at the right temperature for optimum food storage. If your fridge or freezer is not working correctly, a broken thermostat can be the source of the problem.
Replacing your refrigerator’s thermostat is a simple process that requires few tools and only a few minutes of work. In fact, most homeowners have no trouble completing this task without professional help.
Before you begin replacing your refrigerator’s thermostat, be sure to shut off the power to the unit. Doing so will protect your home and prevent you from shocks or shorting out other components in the appliance.
Remove the control panel containing the thermostat dials from your refrigerator using screwdrivers and remove the clips that hold the panel in place. Lower the thermostat, which is a relay with two or three wired connections and a long flexible temperature sensing tube, out of its housing.
Once the thermostat is out of its housing, disconnect all wires from it and set it aside. Next, locate the terminals on your replacement thermostat and connect the old wires to the new thermostat in the same positions they were on the original part. If the wires need to be cut, trim 1/2-inch of insulation from their tips.
Transition the wiring from your old thermostat to your replacement one carefully, using a method that works for you. Some thermostats have a wire harness that clips into the replacement piece, so it’s easy to transfer all of the old wires from the old one to the new one. Others may have multiple wires that require a prong-by-prong transition. Be sure to snap a photo of your wires before beginning the transition to make sure you get it right.
Route the temperature sensing wire in a free air space near the evaporator but away from the main power wiring. Be sure not to touch the evaporator with the wire, as this can damage it and ruin your refrigeration system.
Connect the sensor wires to thermostat terminals 7 and 8. If your electronic thermostat is a single-phase device, attach an in-line fuse of 150 milliamps between the positive lead and terminal 4. Be sure not to include the compressor power wires in the ferrite.
Replace the thermostat controller and plug the refrigerator back into the wall. Test the refrigerator to make sure it has cooled properly after installing the thermostat. If it hasn’t, you probably have a wiring issue and will need to address it first.
When you are done, the refrigerator will run much more efficiently and you will no longer be concerned with storing frozen foods at dangerously low temperatures. It’s also a great way to save money on your energy bill. The only downside is that your refrigerator will take a little time to cool down after the thermostat is installed. However, the benefits are well worth it.