Whirlpool TruCool Refrigerator Not Cooling:... | appliancefaults.com

Technical Background:

The Whirlpool TruCool refrigerator utilizes a dual evaporator system – one evaporator for the freezer and one for the refrigerator. The MCU controls the operation of the compressor, fans, defrost system, and damper door to maintain the set temperatures. The MCU monitors thermistors (temperature sensors) and adjusts components to ensure optimal cooling. Voltage to components such as the evaporator fan motor and compressor passes through the MCU on designated voltage paths.

Symptoms:

The refrigerator section of your Whirlpool TruCool is not cooling, but the freezer might be working normally. Food is spoiling in the refrigerator, and the temperature feels warmer than usual. The control panel might display error codes, or there may be no error indication at all.

Possible Causes:

Defrost system failure
Evaporator fan motor malfunction
Sealed system leak or compressor failure
Damper door malfunction (air flow restriction)
MCU (Main Control Unit) issue
Thermistor failure (temperature sensor)

Solution:

1

Check the evaporator fan motor: Using a multimeter, test for continuity across the fan motor windings. No continuity indicates a faulty motor. Replace if necessary.
2

Inspect the defrost system: Examine the defrost heater element for continuity. A reading of infinity indicates a failed heater. Check the defrost thermostat for continuity when cold (below 40°F). Open circuit indicates a faulty thermostat. Replace faulty parts.
3

Evaluate the compressor: Verify the compressor is running by listening for its operation and feeling for vibration. Use a clamp meter to measure the compressor's amp draw. Compare the reading to the nameplate value. Low or no amp draw suggests compressor issues.
4

Check the damper door: Manually inspect the damper door for proper opening and closing. If the door is stuck or broken, replace it.
5

Verify thermistor functionality: Using a multimeter, measure the resistance of the thermistors. Compare the readings to the temperature resistance chart for your model. Out-of-range values indicate a faulty thermistor. Replace if necessary.
6

Assess the sealed system: If the above components check out, suspect a sealed system issue. Connect gauges to the process ports and check the system pressures. Unusual pressures or signs of a leak require licensed technician repair.
7

Examine MCU: Check for 120V AC at the MCU. Refer to the wiring diagram for correct voltage paths.

Safety Warning:

Disconnect the refrigerator from the power source (unplug it or turn off the breaker) before performing any repairs. Capacitors in the appliance can hold a dangerous electrical charge, even after the power is disconnected. Use caution when working around electrical components. Lock-out/Tag-out procedures are critical.

Prevention:

Regularly clean the condenser coils (located at the back or bottom of the refrigerator) with a vacuum cleaner to ensure proper airflow. Avoid overpacking the refrigerator, which can restrict airflow. Replace the water filter every six months (if applicable).

Expert Tip:

Enter the service mode by pressing and holding the “Freezer Up” and “Refrigerator Down” buttons simultaneously for approximately 5 seconds. This allows you to run diagnostic tests and view error codes. Refer to the service manual for specific service mode functions and tests.

Frequently Asked Questions

•What is the correct resistance range for the refrigerator thermistor at 35°F?

Refer to the Whirlpool TruCool service manual or parts list for the specific resistance value for your model. Typically, it will be around 10k to 15k ohms at 35°F.

•How do I access the evaporator fan in the refrigerator compartment?

Typically, you'll need to remove the back panel inside the refrigerator compartment. This panel is usually held in place by screws. Once removed, the evaporator fan motor will be visible. Be careful not to damage any wiring or tubing.

•What type of refrigerant does the Whirlpool TruCool use, and what are the proper charging pressures?

The Whirlpool TruCool typically uses R-134a refrigerant. The proper charging pressures depend on ambient temperature and operating conditions. Consult the service manual or the sticker on the unit near the compressor for the target superheat and subcooling values, along with pressure charts for the refrigerant.

Whirlpool TruCool Refrigerator Not Cooling: Troubleshooting Guide

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip:

Frequently Asked Questions

•What is the correct resistance range for the refrigerator thermistor at 35°F?

•How do I access the evaporator fan in the refrigerator compartment?

•What type of refrigerant does the Whirlpool TruCool use, and what are the proper charging pressures?

Related questions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip: