by Nick Gromicko, CMI® and Ben Gromicko
A kitchen refrigerator is an appliance that consists of a thermally insulated compartment and a heat pump, which transfers heat from the refrigerator's interior to its external environment. The refrigerator's interior is cooled to a temperature below the ambient air temperature. Refrigeration is essential for storing food, and the cool temperature of the refrigerator's interior helps slow the growth of micro-organisms to prevent spoilage.
The slightly warm air inside the refrigerator comes in contact with the chilled coils and transfers its heat to the gas refrigerant flowing inside the cooling coils. This results in the cabinet interior and its contents to cool down. The warmed refrigerant flows to the compressor, which pressurizes and heats it up. The “squeezed” hot refrigerant leaves the compressor as a super-heated gas that flows to the condenser coils on the back-side of the refrigerator. As the gas flows through the condenser coils, the gas releases its heat to the surrounding air. That’s why it’s warm behind the refrigerator. The refrigerant then cools and condenses into a liquid. The liquid line terminates at the refrigerant control, the capillary tube, which controls the amount of refrigeration that goes to the cooling coils of the evaporator. When the liquid enters the capillary tube, the liquid pressure drops due to a very small diameter of the capillary. The refrigerant leaves the refrigerant control and enters a low pressure environment of the evaporator. Moving through the cooling coils, the refrigerant continues its job of absorbing heat from the food inside the refrigerator.
Styles & Features
Some common types of refrigerators include the following:
- traditional style, with the freezer on the top and the refrigerator on the bottom;
- side-by-side style, with the freezer on the left side and the refrigerator on the right side;
- bottom-mounted style, with the refrigerator on the top and the freezer on the bottom; and
- French-door style, with two doors for the refrigerator on the top and one bottom freezer door compartment.
Some common features include:
- automatic defrosting;
- a power-failure warning that alerts the user by flashing a temperature display;
- chilled water and ice from a dispenser in the door;
- cabinet rollers that let the refrigerator roll away from the wall for easier cleaning behind it;
- adjustable shelves and trays;
- a status indicator that notifies the homeowner when it's time to change the water filter;
- an in-door ice caddy, which relocates the ice-maker storage to the freezer door and saves approximately 60 liters (2 cu. ft.) of usable freezer space;
- a cooling zone in the refrigerator door shelves, which works by diverting air from the freezer section to the refrigerator door to cool milk, juice, and other beverages stored in the door shelf;
- a drop-down door built into the refrigerator's main door, providing easy access to frequently-used items, such as milk, thus saving energy by not having to open the main door; and
- a fast-freeze function that rapidly cools foods by running the compressor for a predetermined amount of time and thus temporarily lowering the freezer temperature below normal operating levels.
According to the InterNACHI Standards of Practice (nachi.org/sop
), the inspector is not required to inspect or move appliances. However, appliance inspection is required by some states' SOPs, and some inspectors offer appliance inspection as part of their standard home inspection. So, it's useful to understand how common household appliances function.
The inspector may attempt to inspect the refrigerator using normal operating controls. A full and comprehensive inspection may need to be deferred to a qualified expert. However, the inspector may exert his/her best effort by referring to the owner's manual (if available) to determine the proper condition and operation of the appliance in order to report any apparent deficiencies, whose further evaluation and repair (if required) must be deferred to a qualified professional.
The inspector may report as deficient:
- inoperative unit(s);
- damage to the exterior or interior of the cabinet or components;
- rust on the exterior or interior of the cabinet or components;
- damaged or missing interior shelving;
- excessive ice or frost formation;
- unusual sounds or vibration levels;
- dirty or damaged coils;
- deficiencies in the:
- door gasket, hinges, closure and handle;
- controls and control panels;
- door operation;
- water valve and location(s); and
- water supply line (if applicable).
The inspector may document:
- Style: _______________________
- Make: _____________________
- Model: ____________________
- Manufacturer: ______________________
- Year Manufactured: ____________________
The refrigerator interior temperature should be kept at the proper temperature. The refrigerator should be kept at or below 40° F (4° C). The freezer temperature should be 0° F (-18° C). The homeowner should check the temperatures periodically. Appliance thermometers are the best way of knowing these temperatures and are generally inexpensive.
Most home refrigerators weigh between 200 and 450 pounds, and some models weight up to 875 pounds.
Current U.S. refrigerator models that are ENERGY STAR-qualified use 50% less energy than the average models made in 1974. The most energy-efficient units made in the U.S. consume about one-half a kilowatt-hour per day. Large refrigerators, especially those with large freezers and ice makers, may use as much as 4 kWh per day.
Check the refrigerator inside and out, paying special attention to any areas corresponding to indications of damage. Look carefully for dents and scratches on both the interior and exterior of the refrigerator.
Open and close the refrigerator and freezer doors to check their operation. Check that the door lights come on and that the doors close evenly and tightly with the frame of the refrigerator. Inspect the gasket material of the door. The door should close and seal tightly, with no gaps that could allow cold air to escape. Door gaskets should not be torn, twisted, or otherwise out of shape to assure that they make a tight seal. Gaskets can be replaced and are not too expensive, but if they need to be replaced, this should lower the price of the used refrigerator.
Open the door and leave it open for a few moments to get the compressor to turn on. The temperature control can also activate the motor. The compressor should operate, and start and stop smoothly, without a noticeable shudder that rattles the refrigerator.
With the door open, the control button should be pressed to see if the light turns off when the door closes.
Where possible, open and close the shelves in and out, inspecting the operation of the glides. If the refrigerator has other features (water, ice maker, etc.), operate those components using normal operating controls.
Check the refrigerator coils. Dust, dirt, debris, pet hair, and other material on the coils will reduce the efficiency of the cooling operation. A dirty coil will force the compressor to run longer to cool the refrigerator.
The refrigerant control divides the refrigeration into two "sides," the high pressure and low pressure sides. The most often used control device for a refrigerator is a capillary tube. The tube is a very thin copper tube, several feet long. Liquid refrigerant enters the tubing at the high pressure liquid line side. When the refrigerant emerges from the tube, its flow rate and volume are significantly lowered. This tube acts like a throttle of the flow of liquid before it enters the evaporator coils. This is important because only a small amount of high pressure liquid is needed to expand to a vapor that can fill the evaporator coils.
The above image is of a capillary tube on a refrigerator.
The refrigerator is a cord-and-plug-connected appliance. Without moving the refrigerator, look for the electrical cord and wall receptacle. Check for indications of damage or improper installation. The receptacle must be accessible and located to avoid physical damage to the flexible cord. The refrigerator should not be plugged into a GFCI-protected receptacle. The refrigerator’s flexible cord must terminate in a grounding-type attachment plug. The receptacle for the refrigerator is permitted to be on the small appliance circuit of the kitchen, it or may be supplied from a dedicated 15- or 20-amp circuit.
If applicable, check the water supply line and water valve, as well as their locations. Look for indications of prior water leaks behind and around the bottom of the refrigerator. Check for ice in the freezer, and make a notation if there is an absence of ice. If applicable, check the water dispenser.
It's important that homeowners take special precautions to safeguard against a child becoming accidentally trapped inside a refrigerator, which can quickly and tragically suffocate a youngster whose absence may not be detected until it's too late. A refrigerator used in the garage or other area outside the home--and away from immediate adult supervision--should be childproofed with a special lock or latch that prevents a child from opening the door. A refrigerator not in use should have its door removed and stored securely so that it will not fall on top of a child. If this is not practical, the unit itself should be stored with its door against the wall to prevent entry. It should also be adequately braced so that it will not fall over if climbed on.