What To Do If The Refrigerator Thermostat Fails?

The refrigerator, that paradise of freshness that keeps glossy tomatoes, fragrant cheese, crisp lettuce, and tuppers in perfect magazine condition… What a catastrophe when it breaks down, right? For this reason, at HomeServe we want to provide you with the necessary knowledge so that you do not panic if your refrigerator has a problem. Today we show you how to fix a fault in the refrigerator thermostat.

The refrigerator thermostat is the device that is responsible for opening or closing the passage of electrical current to the compressor depending on the prevailing temperature inside the refrigerator. The thermostat controls the temperature by means of a probe and when it detects an unwanted variation, it is in charge of sending the signal to the compressor to start working, generating more cold, or to stop it. It is normally located within the same box where the lighting system is located.

How to tell if the refrigerator thermostat is bad

Refrigerator thermostat malfunctions usually manifest themselves in two ways:

1. The refrigerator is not cold. Liquids are warm and when solids are touched, they barely give off any coolness. In the freezer, the food is soft.
2. The refrigerator over cools. So much so that frost begins to grow on some products.

How are the inner workings of a thermostat

Initially, the thermostatic bulb is in contact with the evaporator wall, where the vaporization ends. Temperature variations in the evaporator are detected by the bulb, resulting in variations in fluid pressure, expanding or contracting the diaphragm, or bellows of the thermostat.

These expansion or contraction movements are transmitted by a system of levers and springs that keep the system in tension. These components form a mechanism that amplifies the movements of the bellows and transmits them to the contactors, causing the motor compressor to connect and disconnect when the temperature reaches the maximum and minimum values established

Tests to detect a failure in the refrigerator thermostat

To make sure that it is really the refrigerator thermostat that has gone bad, you should carry out the following tests:

• Lower the regulator temperature to the minimum and listen carefully to see if the noise indicates that the compressor motor has started.
• Retrieve the manufacturer's instructions and verify that you are setting the refrigerator with the correct storage temperature.
• Put a thermometer inside the refrigerator and check if the temperature it marks is within the appropriate range.
• Remove the refrigerator thermostat and see if the device continues to transmit current to the compressor by means of a tester.

If you're not very fond of bottling, you probably don't have a tester handy. For these cases, remember that my colleagues at HomeServe, specialists in appliance repair, are always at your disposal. Let us know!

If the compressor motor does not start, you are following the indications of the brand to the letter and the tester says that there are problems with the electrical transmission, there is no doubt: you have to change the refrigerator thermostat.

How to regulate the thermostat on my refrigerator

To keep the fridge working properly, it is advisable to regulate the thermostat correctly. It is worth mentioning that the proper functioning of the thermostat not only depends on the temperature it reads inside the refrigerator but also on the times you open the refrigerator door, the temperature outside, the amount of food stored, the stability of the supply voltage. electricity from the network, etc.

Here we explain how to adjust the refrigerator thermostat correctly, step by step:

• Like all equipment, the thermostat must bring its instruction manual, so do not hesitate to take a look before connecting the refrigerator for the first time.
• After finding the ideal temperature for both the freezer and the fridge and its different spaces, you must adjust the regulators. For the freezer, which produces a dry cold, the recommended temperatures are around -22 to -4 degrees Celsius. For the lower part of the refrigerator, which produces a humid cold, the ideal temperatures are around 5 ± 3 degrees Celsius.
• When the refrigerator is connected for the first time, it is advisable to place the thermostat in the middle of the selector if it is manual or in the middle of the electronic indicator if it is digital. Plugin the fridge and let it run for a full day before setting the thermostat to how cool you want it.
• Most thermostat selectors have odd-numbered values, generally 1 through 9. Thus, if you want a colder temperature, you will have to set the selector to 7 or 9, and when you want a less cold temperature, you will have to set it to 1 or 3. For normal refrigerator operating temperatures, we recommend setting the selector to 5.

Observe the operation of the refrigerator well; If you see that it freezes and makes frost on the walls of the freezer, it may be that the upper cut-off temperature is wrongly set, that is, too high.

On the other hand, if the refrigerator is slow to start, the starting temperature may be above 8 degrees Celsius. In these cases, you should go to specialists to check the operation of the refrigerator thermostat or other components that may be damaging your appliance.

How to change the refrigerator thermostat

Always replace a faulty thermostat with another compatible with the make and model of your refrigerator. These are the steps you must take:

1. Unplug the refrigerator.
2. With the help of a screw or an Allen key, remove the thermostat housing.
3. Take a look at the wiring layout. Then unplug it and remove the probe.
4. Loosen the screws and nuts that secure the thermostat to the housing, remove it, and put the new one in place.
5. Reinstall all the elements in the refrigerator, making sure to insert the probe correctly and that each connection goes in the appropriate place.
6. Screw the box tightly, regulate the temperature, and plug in the refrigerator. Check that the optimal temperature is reached inside.