Refrigerator Parts and Terms Glossary

This wiki is a glossary for refrigerator parts, their function and general location as well as common terms used. To understand the theory of how your refrigerator works, go to our page How a Refrigerator Works for an explanation of what's going on.

If you need parts for your refrigerator, check out our refrigerator parts pages.

A defrost system that controls defrost cycle frequency based on compressor cycles or other indicators of refrigerator usage. It regulates the defrost process to prevent ice buildup by increasing the defrost cycle frequency with heavier use.  It decreases it when the refrigerator is not running the compressor as often, a sign of lower usage.

The capacitor enables the compressor to start and to run more efficiently. It feeds current to the starting winding of the compressor motor in such a way (phase shift) that it starts the motor turning. Some compressors use the capacitor to run as well and the winding that starts the compressor is used continuously to keep it going more efficiently. Often capacitors are located with the control board. They are either metal cylinders with wires or rectangular plastic components with terminals. Sometimes they are mounted on the side of the compressor (usually rectangular plastic capacitors).

Red Arrows Point to Capillary Tube

The capillary tube is a long copper tube with a very small diameter (it can look like copper wire) Liquid refrigerant from the condenser flows through it and loses pressure and a little more temperature,before it enters the evaporator coils. Often the capillary tube is routed in such a way that it prevents condensation on the outside of the front of the refrigerator by warming the area. This is called a Yoder Loop, and it is usually routed around the perimeter of the door openings.

The compressor is the heart of the refrigeration cycle. It compresses refrigerant gas, raising its temperature and pressure, which starts the cooling cycle. It is usually found in a compartment in the lower rear of the refrigerator. Usually it looks like a black oval or round metal container with tubes entering its sides.

Water that has condensed onto the evaporator coils, usually turning to ice. It is melted by the defrost heater and normally drains through tubes in the rear of the refrigerator to a pan located underneath the lower compartment of the refrigerator where airflow from the condenser fan and heat from the condenser allow it to evaporate.

The finned tubing in the red box is the condenser.	This unit uses wires on the cylindrical condenser.
These coils are under the refrigerator.	Sometimes these coils are accessed through the front, too.

The condenser coils are made of tubing usually with fins or wires attached to help with heat dissipation. The hot, high pressure refrigerant gas flows through the tubing and releases heat, allowing it to liquefy as it cools. These coils are typically located at the back or bottom of the refrigerator. They are frequently in the machinery compartment where the compressor is located. Usually they are cooled by a fan called the Condenser Fan. Keeping this tubing free of dust and debris is an important maintenance task for your fridge.

Condenser Fan in red box

Found in nearly all refrigerators, except for very small units, this fan blows air across the condenser coils to dissipate heat more effectively. It also helps to cool the compressor somewhat by circulating air in the machinery compartment.

A digital interface or dial that allows users to adjust temperature settings, activate special modes (like quick freeze), or control the ice maker and water dispenser. Some are located in the fresh food compartment of the refrigerator, others on the door face, and others on the rim of the door openings.

A PC board usually located in a small covered compartment on the rear of the refrigerator. The compartment is normally not ventilated so dust and moisture are more easily kept out. The control board controls the function of the entire refrigerator. When it fails usually the refrigerator ceases to function or will give error codes or operate erratically.

An electronic device, either a separate PC board, or a part of the main control board which regulates the defrost cycle. This is usually part of an adaptive defrost system.

Defrost Heater shown below evaporator coils

Defrost Heater removed from the same refrigerator

The defrost heater is responsible for melting any frost that accumulates on the evaporator coils, preventing ice buildup. It is located near the evaporator that it serves, usually below it and to the sides so that convection helps to distribute the heat and melt the ice.

This component activates the defrost heater at set intervals to ensure that frost does not accumulate on the evaporator coils. Normally the timer is set to turn on the defrost heater about every 8-10 hours.

This serves to control the temperature of the defrost process. It will shut off the defrost heater if the temperature rises too high. Some units use just a defrost thermostat to control the defrost process.

A rubber seal that lines the edge of the refrigerator door, ensuring that the door closes tightly to prevent cold air from escaping. It is usually magnetic and also functions as a sort of latch for the door.

A tray located at the bottom of the refrigerator where water (melted condensate) collects during the defrost cycle before evaporating. Usually made of plastic, it can occasionally crack or tip if it is installed incorrectly and the refrigerator will leak.

Duckbill Valve in Red Box

A device made out of fairly soft rubber that has two thin leaves of rubber in a “V” shape that touch each other and seal off the bottom of the condensate drain tube so warm air can’t get into the refrigerator, while allowing the condensate to drain. The rubber can harden over time and the valve will not allow the condensate to flow out as rapidly, Alternatively, debris from the freezer can become trapped in the valve, especially when it hardens and can plug it.

Evaporator Coils in the Red Box

Located inside the refrigerator, the evaporator coils are made from tubing with fins for better heat transfer. The cold liquid refrigerant flowing through them absorbs heat from the refrigerator’s interior. The coils are cooled as the refrigerant inside changes from a liquid into a gas as it absorbs heat. A fan is provided to circulate the air in the refrigerator, and cause it to pass over the cold coils, which cools the air in the compartment

Evaporator Fan location (red box)

Evaporator Fan (red box)

The evaporator fan is located in the rear of the freezer compartment and sometimes in the rear of the fresh food (refrigerator) compartment. In either case it is behind a cover. It circulates air over the evaporator coils to cool it and sends it throughout the fridge (occasionally) and (usually) freezer compartments to maintain consistent temperatures. On refrigerators with multiple evaporators, each evaporator will have a fan associated with it. When the evaporator fan fails the ability of the refrigerator to cool will be greatly reduced.

The filter dryer is a component of the refrigeration or sealed system that removes moisture, compressor lubricant and small particles that might clog the capillary tube. It usually looks like a small piece of copper pipe that tapers to small tubes at each end. It may be mounted horizontally or vertically and is found in the machinery compartment of the refrigerator.

The flap door is a device on through door ice dispensers that opens to allow ice to be dispensed. If it sticks open or is jammed by ice it can allow room temperature air into the refrigerator and can cause the freezer compartment to warm up. Often ice in the ice bucket will partially melt and jam the ice auger.

A term used to denote the compartment in a refrigerator where fresh food (as opposed to frozen) is kept at a lower temperature (34-39°F, 1-4°C). Commonly called the refrigerated compartment or refrigerator compartment, manufacturers use “fresh food compartment” to distinguish the compartment from the entire unit called a refrigerator.

A screw like device or blade which rotates and moves ice in the ice bucket to dispense it either by moving it into the ice crusher, or just sending it down the dispensing chute and through the open flap door. It can jam if the ice melts and refreezes.

Twist-Tray Ice Maker

Fixed Mold Ice Maker

A component that automatically produces ice by freezing water in molds and then ejecting it into a storage bin. Some Ice makers use a mechanism like an ice cube tray and twist the tray mechanically to free the cubes. Others heat the ice in a fixed mold momentarily and then sweep the ice out with an ejector with fingers. Many newer refrigerators with through-the-door dispensing and a bottom freezer will have two ice makers, one in the freezer compartment and one in the fresh food compartment area in a small Ice maker compartment or even in the door itself.

LED or incandescent bulbs that illuminate the refrigerator’s interior when the door is opened.

A compartment at the lower rear of the refrigerator where such items as the compressor, condenser, condensate tray, condenser fan, filter-dryer, three-way-valve and condensate drain tubes are located. It usually has a metal, or sometimes heavy fiberboard, cover with vents in it.

A substance that cycles through the refrigeration system, alternately absorbing and releasing heat. It changes from a gas to a liquid (releasing heat), and then back into a gas (absorbing heat). The most common refrigerants are R-134a or R-600a. [How a refrigerator works]

The portion of the refrigerator/freezer that contains refrigerant and is sealed from the atmosphere. The main components are the compressor, condenser, capillary tube, and evaporator.

Interior storage components made of plastic or glass, designed to organize food items. Crisper drawers maintain optimal humidity levels for fresh produce.

Start Relay (red arrow) with a black run capacitor attached

This device is usually found in a small box attached to the side of the compressor. There are several types used with different operating principles. One common type is the PTC relay which uses a resistive device that starts with a low resistance and as current flows it rapidly heats and the resistance rises effectively opening the start circuit. Other types use the heavy current draw when the compressor is starting to connect the start winding. They usually incorporate a thermal protection device as part of the assembly as well as frequently a capacitor.

This electronic board manages the refrigerator’s temperature settings and overall operation by controlling various components like the compressor and fans. On newer refrigerators the main control board performs this function.. On older models you will find it in a control housing located in the fresh food compartment. These usually don’t have digital displays, or at most 0-9 displayed

Thermal Fuse Shown in red box

A device which provides a “last line of defense” for the defrost system. If the defrost heater is stuck on (a number of ways this can happen), the thermal fuse will blow if the temperature rises too high. This protects the refrigerator from potential damage from the defrost heater running away. It sometimes fails just from age and is an easy component to check when the defrost cycle doesn’t work.

The thermostat controls the temperature inside the refrigerator by regulating the compressor’s activity. When the internal temperature rises, the thermostat triggers the compressor to start and cool down the interior. When the set temperature is reached it shuts off the compressor. Thermostats are generally used now only on very small simple refrigerators

Thermistor In Installed Position

This device has electrical resistance which varies in a known way with temperature. On newer refrigerators, it is monitored by the control board which senses the voltage drop across it. Most refrigerators have at least two thermistors and three or more is common. They may monitor such things as: the fresh food compartment temperature, the freezer compartment temperature, the ambient temperature, and the defrost temperature (at each evaporator).

A device on some refrigerators with multiple evaporators that allows the refrigerant to flow to different evaporators or all of them at once. This allows the temperature in each compartment (fresh food, freezer and in some cases pantry drawer) to be individually controlled by controlling the refrigerant flow.

Filters out impurities from the water used in the water dispenser and ice maker, ensuring clean, drinkable water and ice. Usually should be changed at six-month intervals.

A solenoid valve that controls the flow of water to the refrigerator's water dispenser or ice maker. Usually located at the lower rear of the unit. There are often multiple valves in the system so that two valves must open for water to flow. A common point of failure in the water dispensing system.