LG Refrigerator Error Code Er dH

LG Refrigerator Error “Er dH” — What It Means and Why It Happens

The Er dH code on many LG refrigerators typically indicates a fault in the refrigerator’s defrost system — most often a problem with the defrost heater circuit or related sensors and controls. When the refrigerator’s automatic defrost sequence fails or detects abnormal values, the control board can trigger this error to prevent further damage. Common impacts for users include frost or ice buildup on the evaporator, reduced cooling efficiency, higher energy use, thawed or partially thawed food, and in some cases, the refrigerator cycling continuously or running warmer than normal. While the error seldom presents an immediate electrical hazard, prolonged operation with a failed defrost system can lead to increased compressor stress and potential food safety issues due to inconsistent temperatures.

Common Causes

• Failed defrost heater (open or shorted heater element)
• Faulty defrost thermostat or thermal fuse (doesn’t close during defrost)
• Open or damaged wiring harness/connectors in the defrost circuit
• Malfunctioning main control board (failed relay or sensor input)
• Bad evaporator thermistor/temperature sensor reporting incorrect temps
• Severe ice buildup preventing sensors or heater from operating normally
• Failed evaporator fan causing abnormal temperature readings and tripping diagnostics

Troubleshooting Steps

1. Power cycle the refrigerator: unplug or switch off power for 5–10 minutes and then restore power to see if the code clears (this can reset electronics and confirm if the fault is persistent).
2. Check for obvious frost/ice: open the freezer and inspect the evaporator cover area for heavy ice buildup — excessive ice often points to a defrost failure.
3. Run a diagnostic/test mode (if available): consult your model’s service manual to access LG’s diagnostic mode to read error logs and run component tests for the defrost heater and sensors.
4. Inspect wiring and connectors: visually check harnesses around the evaporator and control board for burns, corrosion, or loose connectors. Replace or reseat as needed.
5. Test the defrost heater for continuity: disconnect power, remove the evaporator cover and use a multimeter to check continuity across the heater element; an open circuit usually means a failed heater.
6. Test the defrost thermostat/thermal fuse: measure continuity at room temperature (or per service manual procedure). Replace if open when it should be closed, or if thermal fuse is blown.
7. Check the evaporator thermistor: test resistance at known temperatures and compare to the specification in the service manual — a bad thermistor can send incorrect temp readings.
8. Inspect the main control board: look for visible damage (burn marks, bulging caps) and test outputs if you’re experienced. Boards can be replaced if faulty.
9. Perform a manual defrost: if ice is heavy, defrost the freezer fully (turn off unit and allow ice to melt) then restart and monitor for reappearance of the code — this helps determine if the error returns immediately.
10. When in doubt, call a certified appliance technician: electrical testing of heaters and boards can be hazardous and often requires professional diagnostic tools.

Maintenance / Prevention Tips

• Keep door gaskets clean and in good condition to prevent warm air and moisture ingress.
• Avoid frequently leaving the freezer door open for long periods — this reduces frost buildup.
• Ensure proper clearance around the refrigerator for adequate airflow to the condenser and components.
• Defrost manually if you notice any uneven frost buildup before it becomes severe.
• Clean condenser coils at least twice a year to maintain cooling efficiency.
• Check and replace damaged or worn door seals promptly.
• Don’t overload the freezer; overcrowding can block airflow and cause sensor misreads.
• Use a fridge thermometer to monitor temps so you notice changes early.
• Schedule routine servicing if your unit is older or heavily used.
• Inspect wiring behind the unit occasionally for signs of wear or rodent damage.
• Follow manufacturer recommended defrost and maintenance procedures in the owner’s manual.
• Make sure ice makers and water lines are installed correctly and not interfering with airflow.
• Replace weak or failing components (sensors, thermostats) promptly rather than waiting for failure.
• Keep the freezer evaporator cover area free from spilled food that can freeze and trap moisture.
• Use surge protection to reduce the chance of control board damage during power events.

FAQs

Conclusion & Safety Notice

Er dH usually points to a defrost-related fault. While some basic checks and a manual defrost may temporarily resolve the issue, diagnosing and repairing the root cause often requires electrical testing and component replacement. Always disconnect power before accessing internal components. If you’re unsure, uncomfortable, or the fault involves the main control board or sealed system components, contact an authorized LG technician or a certified appliance repair professional to avoid risk of electric shock, further damage, or voiding warranty.

Prompt attention helps protect food, prevent compressor strain, and extend the life of your refrigerator. When in doubt, call a professional — safe repairs preserve both your appliance and your household safety.