LG Refrigerator Error Code dH

Understanding the LG Refrigerator dH Error Code

The dH code on an LG refrigerator typically indicates a problem with the defrost circuit — commonly a failed defrost heater or an associated sensor/control that tells the fridge when to run a defrost cycle. When the fridge cannot properly defrost the evaporator, ice builds up on the evaporator coils, restricting airflow and reducing cooling efficiency. Users will often see symptoms such as excessive frost or ice in the freezer, longer run-times for the compressor, higher internal temperatures, water pooling or dripping during partial thaw, and ultimately food spoilage if left unaddressed. Beyond inconvenience and energy waste, prolonged frost buildup can strain the compressor and other components and — in rare cases — lead to electrical issues if connectors corrode or short.

Common Causes

• Defrost heater failure (open circuit or burned out)
• Faulty defrost thermistor / sensor or defrost thermostat
• Main control board (PCB) not commanding or sensing defrost properly
• Wiring harness or connector faults (loose, corroded or shorted wires)
• Blocked drain or ice dam causing abnormal icing and sensor confusion
• Evaporator fan motor failure (reduces airflow and leads to frosting)
• Excessive ambient humidity or frequent door openings (secondary contributors)

Troubleshooting Steps

1. Reset power: Unplug the refrigerator (or switch off the breaker) for 5–10 minutes, then restore power to clear transient errors and see if the code returns.
2. Visually inspect the freezer: Open the freezer and look for heavy frost or ice on the evaporator cover or around the coils; thick ice is a key sign of a defrost issue.
3. Run diagnostics (service mode): If available on your model, enter LG service mode to run the defrost test and read stored fault codes — this helps pinpoint which component failed.
4. Check the drain pan and drain tube: Ensure the drain is not clogged; a blocked drain can worsen icing issues and create water leaks.
5. Listen for abnormal operation: If the evaporator fan is not running when the compressor runs, airflow is compromised — this can be part of the problem.
6. Test defrost heater for continuity: With the appliance completely powered off, access the evaporator heater and use a multimeter to check continuity. An open heater indicates replacement is needed. (Only attempt if you are comfortable and qualified.)
7. Test thermistor/defrost sensor: Measure resistance and compare with service specs or swap with a known-good sensor. A failed sensor can prevent defrost cycles.
8. Inspect wiring and connectors: Check the harness from the control board to the heater/sensor for burns, corrosion, or loose pins.
9. Replace suspect parts: Replace the defrost heater, thermistor, or control board only after proper testing confirms the fault. Always use OEM or approved replacement parts.
10. Monitor after repair: Once repaired, clear codes, return the refrigerator to normal operation, and monitor for a few days to ensure the dH code does not reappear.
11. Call a professional: If you’re uncomfortable performing electrical tests, the fault persists after parts replacement, or there are signs of sealed-system problems, arrange service by a qualified technician.

Maintenance / Prevention Tips

• Keep door gaskets clean and sealing properly to prevent moist air infiltration.
• Avoid leaving fridge/freezer doors open for long periods; minimize frequent door openings.
• Allow hot foods to cool to room temperature before placing them inside to reduce humidity load.
• Don’t overpack the freezer — adequate air circulation reduces ice buildup.
• Clean condenser coils every 6–12 months to improve cooling efficiency and reduce run time.
• Check and clear the drain tube/pan periodically to prevent clogs and water backing up.
• Inspect and replace worn door seals to maintain proper internal temperatures and humidity control.
• Level the refrigerator so doors close correctly and drainage works as intended.
• Replace the water filter per manufacturer schedule to reduce internal moisture from leaks or drips (if applicable to model).
• Use recommended temperature settings — too cold can increase frost formation in some cases.
• Schedule periodic professional checkups if you rely on the appliance heavily or store perishable goods long-term.

FAQs

Conclusion / Safety Notice

Working on the defrost circuit involves electrical testing and accessing components behind panels. Always disconnect power before performing inspections or measurements. If you are not experienced with multimeters, wiring, or appliance repair, stop and contact a qualified appliance technician. Attempting complex repairs without proper training can cause injury, further damage to the refrigerator, or void warranties.

If the dH code returns after basic troubleshooting, or if testing identifies a failed heater, thermistor, or control board, schedule professional service to ensure correct diagnosis and safe replacement. Fast action helps prevent further damage and protects your food and family.