Whirlpool Refrigerator: Clicking Sound - Start Relay vs.... | appliancefaults.com

Technical Background:

The Main Control Unit (MCU) sends a signal to the compressor relay. This relay closes, energizing the compressor motor windings (start, run, and common). The start relay assists in starting the compressor. The overload protector prevents the compressor from overheating by interrupting the power supply if the motor draws excessive current. The voltage path is typically 120V AC from the breaker panel, through the power cord, to the MCU, then to the compressor relay, start relay and compressor.

Symptoms:

US homeowners often describe a recurring clicking sound coming from the back of the refrigerator, usually near the compressor. The refrigerator may not be cooling properly, or the compressor might cycle on and off frequently before eventually failing to start.

Possible Causes:

Failed start relay: The relay contacts are burnt or broken, preventing the compressor from starting.
Overloaded compressor: The compressor is working too hard due to a refrigerant leak or other issue, causing it to overheat and cycle on and off.
Compressor motor winding failure: One or more of the compressor motor windings are shorted or open, preventing the compressor from running.
Loose wiring connection to the start relay or compressor: A loose connection can cause intermittent power to the compressor, resulting in a clicking sound.
Defective overload protector: The overload protector is tripping prematurely, interrupting the power supply to the compressor.
Low voltage to the refrigerator: Insufficient voltage can prevent the compressor from starting properly.

Solution:

1

Unplug the refrigerator from the outlet.
2

Access the compressor area at the rear of the unit using a 5/16-inch socket to remove the access panel.
3

Visually inspect the start relay and overload protector. Replace the start relay if it shows signs of damage or burning.
4

Use a multimeter to test the start relay for continuity. A healthy start relay should have a resistance value appropriate for the model; an open circuit indicates failure.
5

Check the voltage at the outlet using a multimeter. It should read approximately 120V AC. Low voltage can stress the compressor.
6

Check compressor windings with an ohmmeter for shorts to ground.
7

If the start relay is good, and the voltage is correct, compressor replacement may be necessary. Consult a qualified technician for refrigerant recovery and compressor replacement.

Safety Warning:

Always disconnect power to the refrigerator before performing any repairs. Lock Out/Tag Out (LOTO) procedures should be followed. Capacitors may store a charge; discharge them before touching any components. High voltage is present when the refrigerator is plugged in.

Prevention:

Clean the condenser coils regularly (every 6 months) using a vacuum cleaner with a brush attachment. Ensure adequate ventilation around the refrigerator.

Expert Tip:

Many Whirlpool refrigerators have a diagnostic mode that can display error codes or run system tests. Consult the service manual for the specific model to access the diagnostic mode. Typically, you can enter it by pressing a specific sequence of buttons on the control panel.

Frequently Asked Questions

•What resistance value should I expect on a good compressor winding?

Compressor winding resistance values typically fall between 2-15 ohms per winding. Check the service manual for your specific model for precise values.

•How do I safely discharge a capacitor in the refrigerator?

Use a resistor (10k ohm, 5-watt) with insulated alligator clips on each end. Connect one clip to each terminal of the capacitor for several seconds.

•What type of start relay does my refrigerator use?

Start relays come in various types, including PTC (Positive Temperature Coefficient) and current relays. Check the parts diagram or the label on the existing relay to identify the correct replacement type. Common part numbers can often be found online using the appliance model number.

Whirlpool Refrigerator: Clicking Sound - Start Relay vs. Compressor Failure Troubleshooting

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip:

Frequently Asked Questions

•What resistance value should I expect on a good compressor winding?

•How do I safely discharge a capacitor in the refrigerator?

•What type of start relay does my refrigerator use?

Related questions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip: