No one wants to go back to using ice boxes to keep food fresh--except maybe the iceman. Instead, we'll keep paying the electric bill and enjoying cold leftovers. And we live in confidence that if it's broken, we can fix it.

How Does It Work?

A refrigerator is a large appliance for chilling food. A motorized compressor forces refrigerant through two sets of metal coils. In one set, the refrigerant becomes a gas and absorbs heat. In the other set, the gas changes into a liquid and disperses that heat to the room air.

Most refrigerators today have a system for eliminating frost. A timer turns on a defrost heater about every 12 hours to warm the evaporator coils on the back of the refrigerator. Some freezers also include an automatic defroster while others must be defrosted manually. The melted frost from either system drains into a pan under the refrigerator and evaporates.

What Can Go Wrong?

Before taking anything apart, first make sure that the cause isn't misadjusted refrigerator or freezer controls, typically located inside and at the back of the refrigerator.

Refrigerator-freezer units are relatively trouble free. Repairs to the sealed refrigeration system, the compressor, condenser coils, and evaporator coils, are best left to a professional. But repairs to most other parts are relatively easy. Lint and dust clogging the condenser coils is one of the most common refrigerator problems. When airflow across the coils is blocked, the unit may run continuously or not run at all. Regular vacuuming of the coils will prolong the life of any refrigerator. The refrigerator may stop operating. The unit may cycle too often. Food may not be kept cool enough or be kept too cold. The defrost system may fail. The refrigerator may make too much noise. Door seals may fail.

How Can I Identify the Problem?

If the refrigerator does not run at all, make sure power is on at the electrical receptacle and test the electrical cord. Check the thermostat and adjust. Test the thermostat. Clean the condenser coils if needed.

If the unit short cycles, clean dirty condenser coils. Next, test the fan motor  and replace it if necessary.

If food in the refrigerator is not kept cold enough, check the thermostat setting and test it if necessary. Also make sure the condenser coils are clean, test the fan motor, check the door gaskets, and replace them if needed (see below).

Look for obvious damage, debris, or other factors that may cause problems. If necessary, you can open the control panel and check for visible problems. Consider calling a refrigerator technician for anything more.

If food is too cold, check the thermostat setting and test the thermostat.

If the refrigerator does not defrost as it should, the defrost heater may need replacing by a professional.

If the refrigerator makes too much noise, try leveling it with the adjusting feet.

If the unit makes a frequent metallic noise, test the fan motor .

If the door seals fail, replace them (see below).

Fix-It Tip

To operate efficiently, a refrigerator must be level. To level a refrigerator, place a bubble-type level on the top of the unit and use a wrench to lengthen or shorten the front feet of the refrigerator. You may need to remove the front kick-cover to access the feet.

What Parts, Materials, and Tools Do I Need?

If you suspect that the controls are defective, unplug the refrigerator and remove the cover to the controls, typically at the back of the interior.

Replacement parts are available from the manufacturer and aftermarket suppliers. More conveniently, you may be able to find replacement parts through the retailer that sold you the refrigerator or at an appliance parts store. The tools you'll need to fix a refrigerator-freezer unit include these:

• Screwdrivers
• Wrenches
• Multimeter

What Are the Steps to Fixing It?

Fix-It Tip

You can realign a warped door by loosening the gasket retaining screws slightly, then grasping the door and twisting it until the door fits flush against the frame when it is closed. Retighten the screws.

Test and replace door gaskets:

1. Test the door seal in several places by closing a piece of paper in the door, then pulling it out. There should be some resistance, indicating that the door is sealed.
2. Remove the old gasket one section at a time. Some gaskets are held on by retaining strips, others by screws or even adhesive.
3. Install an identical gasket using the retaining strips or screws, or new adhesive.

Fix-It Tip

Refrigerator door hinges (located on the top- and bottom-front of the doors) can work themselves loose. You can tighten a loose door hinge using a screwdriver or nut driver. Some hinges have a plastic cover over them that must first be pried off.