Refrigerator Maintenance

Main Working Parts of a Refrigerator

Refrigerators, in some ways, have changed quite a bit since 1835, when the “father of the refrigerator” (Jacob Perkins) received a patent for a vapor-compression cycle. While modern refrigerators certainly have more features and capabilities, many of the essential components and functions have amazingly stayed the same. The essential function of refrigerators is to use the evaporation of a liquid (refrigerant) to absorb heat. The main working parts of a refrigerator include: a compressor, a condenser, an evaporator, an expansion valve, and refrigerant.

Refrigerant

Refrigerant is truly the lifeblood of a refrigerator. It starts in the form of a gas, then a liquid, and back to a gas as it cycles through the refrigerator’s parts. This is the process that cools the refrigerator. In the early stages of refrigerator technology, toxic gases such as ammonia were used as refrigerant. That changed in the 1930’s, when manufacturers began using freon instead. Freon was used for many decades until recent discoveries by scientists found it was harmful to the Earth’s environment. Most modern refrigerators now use a compound called HFC 134a.

Compressor

The refrigerator cooling process begins in the compressor. A motor powers the compressor, which increases the temperature and pressure of the gas (refrigerant) and sends it along to the condenser. The compressor is typically found along the bottom of the refrigerator, towards the back. The exception is with built-in refrigerators, which usually place the compressor(s) on top.

There is a condenser motor and a fan

FMM: The compressor on our refrigerator is behind the panel on the back of the refrigerator at the bottom.

Condenser

The condenser is where the refrigerant liquefies. The condenser receives the hot vapors, which are cooled down into a liquid. Its distinguishable by its large copper coils, and you can find them along the bottom or at the back of your unit.

FMM: Ours is behind the plate at the bottom on the back of the refrigerator. Remove the plate and vacuum as much dust and dirt as possible.

Expansion Valve (Or Capillary Tube)

This cooling process then shifts to the expansion valve, which is a thin set of copper tubes. The expansion valve lowers the liquid refrigerant’s temperature and pressure dramatically, causing about half of it to evaporate. This refrigerant repeatedly evaporating at extremely low temperatures is what creates the cool temperatures inside your refrigerator and/or freezer.

Evaporator

The evaporator is where the cooling process ends and begins the process of the next cycle. It takes the remaining refrigerant liquid and turns it back into a vapor, which the compressor takes to start it all over again. The purpose of the evaporator fan in a refrigerator is to circulate cold air from the evaporator coils throughout the food storage compartments. The evaporator coils are usually located behind the freezer compartment, and the evaporator fan should be right in front of them, although it may be offset to one side or the other.

Frost building up solely on the back of the freezer section, where the evaporator coil is located, indicates an issue with the defrost cycle. Depending on the appliance, this could be either a defective heater, bimetal, defrost sensor, defrost timer or control board. Further troubleshooting is needed to pinpoint what exactly is needed to resolve the issue.

When the freezer compartment fan or evaporator fan fails, the temperature in both compartments rise.

If your freezer stops getting cold but you can hear the condenser motor in the refrigerator working, there’s a good chance the problem is with your evaporator fan motor. The evaporator fan can be found behind the rear panel of the freezer and testing it yourself can help you troubleshoot freezer issues and save you money in repairs.

How to Test an Evaporator Fan Motor

Open the freezer door and look for light. If your freezer is equipped with an internal light bulb, it should turn on when you open the door. If it doesn’t, the problem may be that the freezer isn’t getting power, rather than an issue with the evaporator fan motor.

Feel for cold air in the freezer. If the evaporator fan motor stops working, your freezer will begin to defrost. Open the freezer door and feel for cool air with your hand. If the freezer isn’t working, you should be able to tell quickly. If the freezer is cold, there likely isn’t an issue with the evaporator fan motor.

Most freezers don’t run the evaporator fan motor when the door is open, so if the fan does work, it will turn off when you open the door.

Find the freezer door switch. Your freezer will have a switch that is pressed by the door itself as it closes. As the door opens, the switch depresses, turning on the light and turning off the evaporator fan motor. Look around the door frame of the freezer to find the switch. You can usually find the switch low on the frame of the freezer door.

Press and hold the switch for a minute. The freezer light should turn off and the evaporator fan should kick on after a few seconds. If it turns on, you should be able to clearly hear the electric motor activate and then a low hum from the fan spinning. If the fan motor does not turn on while you hold the switch, the motor is probably bad. If you can hear the fan motor running but the freezer isn’t cold, the issue likely is not with the evaporator fan motor.

Listen for a squeal or chirp sound. If the evaporator fan motor is going bad, it may still run while making a high pitched sound that may come and go. If you hear that sort of sound, something may be caught in the fan blades or the motor may be dying. If you hear a high pitched sound, you will need to remove the rear panel to gain access to the fan motor.

If you remove the rear panel of the freezer to gain access to the evaporator fan motor and find that the coils below the fan are completely frozen over, the fan motor may be fine and your issue may be something else.

How To Maintain Your Refrigerator

These six maintenance steps will prevent most refrigerator breakdowns. Spend 30 minutes on these simple maintenance steps to keep your fridge running in tip top shape. It's hard to believe, but six simple maintenance steps will prevent almost 100 percent of refrigerator breakdowns and eliminate those service calls.

Step 1: Clean the refrigerator condenser coils

You can eliminate more than 70 percent of service calls with this simple cleaning step.

CAUTION: Always unplug your fridge before working on it!

Remove the grille. Unsnap the grille at the bottom of the refrigerator to access the coils. If your coils are located on the back, you’ll have to roll the fridge out to get at them.

Do it twice a year or more often if you have shedding pets. Their fur clogs up the coils fast. Condenser coils are located on the back of the fridge or across the bottom. These coils cool and condense the refrigerant. When the coils are clogged with dirt and dust, they can’t efficiently release heat. The result is your compressor works harder and longer than it was designed to, using more energy and shortening the life of your fridge. Clean the coils with a coil cleaning brush and vacuum.

Step 2: Clean the refrigerator condenser fan and drip pan

Remove the lower back cover. Access the condenser fan by rolling the fridge away from the wall and removing the lower back cover with a screwdriver. Replace the cover when you’re finished. It’s essential for good air circulation.

If the coils are located on the bottom of the fridge like ours, clean the condenser fan and the area around it. The fan circulates air across the coils to help cool them. At times, paper, dirt, dust and even mice can get sucked into the fan and bring it to a complete stop.

It’s always next to the compressor. Most refrigerators will have a diagram on the back or folded up under the front grille showing the location of the major parts. While you’re under there, wipe out the drip pan, a flat pan that collects water from the defrost cycle and allows it to evaporate.

The frost-free refrigerator, the most common today, uses a heater to melt ice on the evaporator coils. The heater is turned on by a timer and automatically shuts off. An evaporator fan distributes the cold air through the freezer. Many models have an opening under the crisper drawers to draw water to the drip tray underneath.

Step 3: Wipe down the refrigerator door gasket

Clean the door gasket. Wipe the door gasket regularly with warm water and a sponge. Don’t use detergent—it can damage the gasket.

Prevent an expensive gasket repair bill ($100 to $200) and cut down air leaks by keeping your door gasket clean. Syrup, jelly or any other sticky stuff dripping down the front sides of your refrigerator can dry and glue the gasket to the frame. The next time you open the door, your gasket can tear. Keep it clean and you’ll get a nice, tight seal, keeping the cool air where it belongs, in the fridge.

To prevent wear, lubricate the door handle side of the gasket by sprinkling baby powder on a cloth and wiping it down once a month.

Step 4: Clear the freezer vents

Keep the freezer vents unobstructed Clear food packages away from the vent openings and clean the air return so crumbs and twist ties don’t clog them.

These little vents on frost-free fridges allow air to circulate in the freezer. Don’t block them or let crumbs or twist ties get sucked in around the evaporator fan or clog the drain tube. To help save energy, keep your freezer about three-quarters full to retain cold air. But don’t pack it any fuller because the air needs to circulate.

Step 5: Set the refrigerator temperature controls

The optimum setting for your fridge is between 38 and 42 degrees F; the freezer, between 0 and 10 degrees.

This step won’t necessarily prevent a repair, but it’ll extend the life of your fridge by allowing it to run more efficiently, which reduces your electric bill. Your fridge has at least two temperature controls (except on manual defrost types, which have one). The one for the food compartment is a thermostat that turns the compressor on and off. The second, for the freezer, is just an air baffle. The baffle lets cold air from the freezer sink into the food compartment. Closing the baffle makes the freezer colder.

Step 6: Clear and clean the drip openings

Locate the drip cup. Find the drip opening on your fridge.

Drip openings allow water that has melted from the defrost cycle to flow down to a pan located by the compressor, where it evaporates. Check your owner’s manual for the location on your fridge. On cycle-defrost fridges, a channel directs the water to a tube in the food compartment.

On frost-free refrigerators, look for a small cap under the crisper drawers that covers a hole, or an opening in the back of the freezer or refrigerator. If the drain opening clogs, water will build up under the crisper drawers and eventually leak out onto the floor.

Best Practices

If you periodically take care of the maintenance tasks listed above, you can expect years of faithful service from your refrigerator. But there’s even more you can do to make sure it remains efficient and fresh smelling.

1. Keep your refrigerator and freezer as full as possible without cramming items in. This helps your energy efficiency because solids and liquids hold cold temperatures better than air, so refrigerators don’t have to work as hard to keep full spaces cold. Just make sure there’s plenty of room for air circulation around the items on the shelves, and avoid blocking any cooling vents. If you’re low on groceries, fill up a few containers of water to store inside.

2. In the freezer, make a point of dumping out your ice bin every couple of months and giving it a thorough cleaning. Old ice can collect odors and flavors, so you probably won’t want to risk ruining a drink with it, but it doesn’t have to go to waste. If you have a garbage disposal, send those old cubes into the grinder with cold running water. The ice cubes will scour the blades and insides of the disposal, scraping away bacteria and removing odors.

Troubleshooting

Service specialists will be the first to admit: A ton of their callers don’t require repair service at all. The solutions are so easy they don’t even require a toolbox. Before you pick up the phone, check the following list. It just might save you $70 and a bit of embarrassment.

Got power?

Check the circuit breaker or fuse box to be sure power’s coming to the outlet.

Is the cord plugged in tight? Wiggle it around a little. A worn receptacle could let the plug fall out just enough for the connection to fail.

Plug a light or any other electrical device into the outlet to see if it works. If it doesn’t, you’ve got an electrical problem, not a refrigerator problem.

Check for a loose, worn or frayed power cord. Rodents often chew through a wire. Sometimes cords loosen when the fridge is moved.
What if you have power but poor cooling?

Make sure the thermostat is turned on and set right. On some models the dial is easily bumped, shutting the fridge down. Or kids could have messed with it.

Your fridge is running all the time but the food’s still warm.

Vacuum the coils. Dirty coils can eventually cause the overload protector on the compressor to shut the fridge down. It’ll automatically come back on when the compressor cools, but by then your food is usually warm.

Is the condenser fan jammed? (This applies only to fridges with the coils on the bottom.) Remove any obstacles and clean it thoroughly. Unplug the fridge and turn it a few times and see if it comes on. If it’s still not working, you’ll have to replace it.

Is the light turning off when the door’s closed? That little light bulb can raise the temperature in the fridge substantially. To check it, close the door and use a butter knife to pull the gasket slightly away from the frame. If light shines out, the switch is bad or slightly out of alignment. Until you fix the switch, loosen the light bulb so it goes out.

Look for ice buildup (frost-free fridges only) bulging on the inside walls or the floor of the freezer. Manually defrost the freezer by unplugging it. It’s only a temporary fix, so call for service.