GE Refrigerator H1 Error: Evaporator Thermistor... | appliancefaults.com

Technical Background:

The H1 error code on a GE Profile refrigerator indicates an issue with the evaporator thermistor circuit. The main control unit (MCU) monitors the voltage signal from the evaporator thermistor. The thermistor is a temperature-sensitive resistor; its resistance changes with temperature. The MCU interprets this resistance change as a temperature reading. If the MCU detects an out-of-range voltage (indicating a faulty thermistor or circuit), it triggers the H1 error.

Symptoms:

The refrigerator displays an "H1" error code on the control panel. The freezer compartment may not be cooling properly, or the refrigerator may cycle frequently.

Possible Causes:

Faulty evaporator thermistor
Wiring harness issue between the thermistor and the main control board
Loose connection at the main control board
Defective main control board
Ice buildup around the evaporator thermistor

Solution:

1

Disconnect power to the refrigerator at the breaker panel.
2

Locate the evaporator thermistor. This is typically behind the rear panel inside the freezer compartment. You'll likely need a 1/4-inch nut driver to remove the panel screws.
3

Inspect the wiring harness and connections for any signs of damage or corrosion.
4

Using a multimeter, measure the resistance of the thermistor. Refer to the service manual for the correct resistance value at the measured temperature. A typical thermistor might read 5k ohms at 77 degrees Fahrenheit. If the resistance is significantly out of range, replace the thermistor.
5

If the wiring and thermistor check out, inspect the main control board for any signs of damage, such as burned components. The main board is usually located at the rear of the refrigerator. Measure voltage at the thermistor connection on the board, typically 5V DC.
6

If the main control board looks damaged or all other components test correctly, consider replacing the main control board.
7

Reassemble the refrigerator, restore power, and monitor for the H1 error code. Ensure proper temperature operation.

Safety Warning:

Always disconnect power to the appliance at the breaker panel before performing any repairs. Lockout/Tagout (LOTO) procedures should be followed to prevent accidental energizing of the circuit. Some components may carry 120V AC even when the refrigerator is seemingly off.

Prevention:

Regularly defrost the freezer compartment to prevent ice buildup around the evaporator and thermistor. Check the door seals for proper sealing to prevent excessive frost.

Expert Tip:

After replacing the thermistor, force a defrost cycle through the service mode. To access service mode, simultaneously press and hold the 'Freezer Up' and 'Refrigerator Down' buttons for 5 seconds. Then navigate using the same buttons to the defrost test.

Frequently Asked Questions

•How do I access the service manual for my specific GE Profile refrigerator model?

The service manual can often be found online by searching for the model number followed by 'service manual.' You can also purchase a physical copy from appliance parts suppliers.

•What is the acceptable resistance range for the evaporator thermistor at room temperature (70-75 degrees F)?

While it varies by model, a general range for a GE evaporator thermistor at 70-75 degrees Fahrenheit is between 3k and 6k ohms. Consult the service manual for the precise value for your model.

•Can a faulty defrost heater or defrost thermostat cause the H1 error code?

While the H1 code directly points to the evaporator thermistor circuit, a malfunctioning defrost heater or defrost thermostat can lead to excessive ice buildup on the evaporator coil. This ice can insulate the thermistor, causing inaccurate readings and potentially triggering the H1 error.

GE Refrigerator H1 Error: Evaporator Thermistor Replacement Guide

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip:

Frequently Asked Questions

•How do I access the service manual for my specific GE Profile refrigerator model?

•What is the acceptable resistance range for the evaporator thermistor at room temperature (70-75 degrees F)?

•Can a faulty defrost heater or defrost thermostat cause the H1 error code?

Related questions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip: