Cause 1
Condenser Coils are Dirty
The condenser coils are usually located under the refrigerator. They dissipate heat as refrigerant passes through them. If the condenser coils are dirty, they won’t dissipate the heat effectively. As debris builds up on the coils, the refrigerator becomes less efficient, causing the refrigerator to work harder to cool down. If the coils are significantly dirty, the refrigerator will not be able to maintain the proper temperature. Check the condenser coils to determine if they are dirty—if the condenser coils are dirty, clean them.
Cause 2
Condenser Fan Motor
The condenser fan motor draws air though the condenser coils and over the compressor. If the condenser fan motor is not working properly, the refrigerator won’t cool properly. To determine if the fan motor is defective, first check the fan blade for obstructions. Next, try turning the fan motor blade by hand. If the blade does not spin freely, replace the condenser fan motor. If no obstructions are present and the fan blade spins freely, use a multimeter to test the fan motor for continuity. If the condenser fan motor does not have continuity, replace it.
Cause 3
Evaporator Fan Motor
The evaporator fan motor draws air over the evaporator (cooling) coils and circulates it throughout the refrigerator and freezer compartments. Some refrigerators have more than one evaporator fan motor. On refrigerators with only one evaporator, the evaporator is located in the freezer compartment. If the evaporator fan is not working, it will not circulate the cold air to the refrigerator compartment. If this occurs, the freezer may still get cold, while the refrigerator will not get cold. To determine if the evaporator fan motor is defective, try turning the fan blade by hand. If the fan blade does not turn freely, replace the fan motor. Additionally, if the motor is unusually noisy, replace it. Finally, if the motor does not run at all, use a multimeter to test the motor windings for continuity. If the windings do not have continuity, replace the evaporator fan motor.
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3 Comments
Update: The compressor is decently hot and the current seems to be reaching the compressor using a non-contact voltage tester.
by Alexandre Lacoste
my freezer is cooling slowly and before was warm why?
by mulwad
For future reference, a non-contact voltage tester is ok for some things. But this isn't one of them. It shows voltage is getting to the unit. Is it the right amount of voltage? It can't say. It also can't tell you if your start components have failed. Or if the compressor is seized and pulling Lock Rotor Amps (LRA). Or if it is thermally out. You need a multimeter to check these things. If you have to diagnose something like this, you want to first check if the compressor is pulling any amperage. Put the clamp around the black wire and see what it says. If it is reading at or a bit below the Run Load Amps (RLA), then move on to other things. If reading zero, time to find out why. Use a good cap checking meter to read the start capacitor. Average multimeters can't read that high, but a decent meter for this is $20. If the cap is reading nothing, or lower than the value on the label, it's bad. Replace it. If good, move on. Check continuity through the start relay. Is it closed? There are different types of relays, so I can't say what pin numbers apply to any given unit. But on the compressor there is Common (c), Run (r), and Start (s). 3 pins. The wire from the start pin should have continuity through the relay to the start cap. If it doesn't, it's bad and needs replaced. If it does, keep going. Time to check the compressor. Ohm between s and c, then r and c, and then s and r. S and r should read close to the other two readings combined. If it says OL from c to s or r, might be thermalled out, you'll have to wait for it to cool down. If it isn't hot and it shows OL, bad compressor. If s to r shows OL, bad winding in compressor. Needs replaced. That should get people a ways into diagnosing.
by brandon k