Whirlpool TruCool: Troubleshooting Temperature... | appliancefaults.com

Technical Background:

The TruCool system uses an air damper to regulate the flow of cold air from the freezer to the refrigerator compartment. The Main Control Unit (MCU) monitors thermistor readings and controls the damper motor, opening and closing the damper to maintain the set temperature. The MCU supplies 12V DC to the damper motor via a dedicated voltage path.

Symptoms:

The homeowner observes temperature fluctuations within the refrigerator compartment. Food may spoil prematurely, and the refrigerator may run more frequently than usual. The freezer temperature might be colder than normal while the refrigerator section is too warm.

Possible Causes:

Damper motor failure
Damper door binding or obstruction
Faulty damper control board (MCU)
Wiring harness issue between the MCU and damper motor
Iced-over damper preventing movement
Incorrect thermistor readings affecting damper operation

Solution:

1

Unplug the refrigerator from the 120V AC outlet or turn off the dedicated breaker.
2

Locate the air damper assembly, typically in the refrigerator section, near the top.
3

Inspect the damper door for any visible obstructions (food items, ice buildup).
4

Using a multimeter, check the damper motor wiring harness for continuity. A lack of continuity indicates a broken wire.
5

Test the damper motor itself. If accessible, apply 12V DC directly to the motor leads to see if it operates. If it doesn't, replace the motor.
6

If the motor tests good, suspect the damper control board (MCU). Check the voltage output to the damper motor when the refrigerator calls for more cold air. You should see approximately 12V DC. If not, replace the MCU.
7

Ensure the thermistor near the damper is functioning correctly. Replace if readings are inaccurate.

Safety Warning:

Disconnect power to the refrigerator before performing any repairs. Lock-Out/Tag-Out (LOTO) procedures should be followed. Be aware of high voltage components within the control panel. Capacitors can hold a charge even after the unit is unplugged.

Prevention:

Regularly check the refrigerator for proper sealing of the door. Avoid overfilling the refrigerator, which can obstruct airflow. Periodically clean the refrigerator, removing any spilled food items that could potentially obstruct the damper.

Expert Tip:

Some Whirlpool TruCool models have a diagnostic mode that allows you to manually cycle the air damper. To enter service mode, simultaneously press and hold the “Freezer Temperature Down” and “Refrigerator Temperature Up” buttons for 5 seconds. Then use those same buttons to navigate to the damper test.

Frequently Asked Questions

•Where is the air damper assembly located on my Whirlpool TruCool?

The air damper assembly is typically located in the upper section of the refrigerator compartment, often behind a plastic panel.

•How do I test the damper motor with a multimeter?

Disconnect the wiring harness from the damper motor. Set your multimeter to ohms (resistance). Touch the meter probes to the motor terminals. You should get a reading, if the meter reads OL or infinite resistance, the motor is likely bad.

•What is the part number for the replacement air damper motor for a Whirlpool TruCool?

The part number varies depending on the exact model of your TruCool refrigerator. Refer to your refrigerator's parts diagram or use your model number to search for the correct replacement part on a parts website.

Whirlpool TruCool: Troubleshooting Temperature Fluctuations Due to a Stuck Air Damper

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip:

Frequently Asked Questions

•Where is the air damper assembly located on my Whirlpool TruCool?

•How do I test the damper motor with a multimeter?

•What is the part number for the replacement air damper motor for a Whirlpool TruCool?

Related questions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip: