January 6, 2015

How a refrigerator works

By Sears PartsDirect staff
Learn how a refrigerator works.
Learn how a refrigerator works.

If you work up a sweat and then stand in front of a fan, your skin feels cooler instantly, because the moisture on your skin is evaporating. When a liquid evaporates, it absorbs heat, making you feel cooler.

Refrigerators operate on the same basic principle: the absorption of heat from inside the refrigerator by evaporation. But your refrigerator doesn’t sweat, so what causes the cooling? It’s done by the evaporation of a substance called a refrigerant. 

Your refrigerator doesn’t have pores that release sweat, so the refrigerant must be carried throughout the refrigerator in a complete loop of tubes and coils, to be continuously reused. It also must be forced to evaporate and condense. This process is accomplished by creating suction and pressure.

The basic cooling components are as follows:

  • Refrigerant

  • Compressor

  • Condenser

  • Capillary tube

  • Evaporator

Here’s how the process works:

  1. The compressor acts as a sort of pump, drawing the refrigerant in gas form from the evaporator.  The compressor squeezes and heats this gas.

  2. The super-heated, pressurized refrigerant gas enters the condenser coil, located either under or behind the refrigerator.

  3. As the refrigerant passes through the condenser, the heat it carries dissipates, causing the gas to cool and condense into a liquid.

  4. The pressurized liquid refrigerant passes through a narrow tube called a capillary tube, which acts much like a nozzle on an aerosol can.  From the capillary tube, the refrigerant enters the evaporator as a vaporized gas—it evaporates and absorbs the heat inside the refrigerator.

  5. The refrigerant is sucked back into the compressor, where the cycle begins again.

Symptoms common to all refrigerators

Choose a symptom to see related refrigerator repairs.

Main causes: leaky door gasket, defrost system failure, evaporator fan not running, dirty condenser coils, condenser fan not running
Main causes: blocked air vents, compressor problems, condenser or evaporator fan not working, control system failure, sensor problems
Main causes: jammed ice cubes, broken ice maker assembly, dirty water filter, kinked water line, bad water valve, freezer not cold enough
Main causes: water valve leaking, frozen or broken defrost drain tube, overflowing drain pan, cracked water system tubing, leaking door seal
Things to do: clean condenser coils, replace the water filter, clean the interior, adjust doors to prevent air leaks, clean the drain pan
Main causes: damaged door seal, faulty defrost sensor or bi-metal thermostat, broken defrost heater, bad defrost timer or control board
Main causes: control board or cold control failure, broken compressor start relay, compressor motor failure, defrost timer problems
Main causes: blocked vents, defrost system problems, evaporator fan failure, dirty condenser coils, bad sensors, condenser fan not working

Repair guides common to all refrigerators

These step-by-step repair guides will help you safely fix what’s broken on your refrigerator.

How to replace a refrigerator temperature control board

If the temperature in your refrigerator doesn't match the temperature you set, the problem could be the temperature control board—a service technician can give you a definite diagnosis. If the board is at fault, follow these steps to replace it yourself.

Repair difficulty
Time required
 30 minutes or less
July 20, 2015
By Lyle Weischwill
How to clean refrigerator condenser coils

Help your refrigerator run more efficiently by cleaning the condenser coils. It's easy and takes just a few minutes.

Repair difficulty
Time required
 15 minutes or less
July 20, 2015
By Lyle Weischwill
How to replace a refrigerator water valve

Replace the water valve that feeds water to the ice maker and water dispenser if it no longer controls the flow of water.

Repair difficulty
Time required
 30 minutes or less

Articles and videos common to all refrigerators

Use the advice and tips in these articles and videos to get the most out of your refrigerator.

May 23, 2016

Diagnosing refrigerator thermistor problems video

By Sears PartsDirect staff

If your refrigerator isn't cooling at the right temperature, the problem could be the thermistor. Here's how to check.

January 27, 2016

How to purge air from a refrigerator water dispenser video

By Sears PartsDirect staff

Follow the steps in this video to remove air from the water line connected to your refrigerator's water dispenser so the water dispenses smoothly.

January 18, 2016

Troubleshooting an Er If error code on a refrigerator video

By Sears PartsDirect staff

Learn how to fix your refrigerator if it's displaying an Er If error code.