LG Refrigerator ER DH Error: Defrost Heater Error
LG refrigerator error — here’s what you need to know. The Er dH error code on your LG refrigerator indicates a defrost heater failure — the heater is not melting frost from the evaporator coils as required. This is a High severity issue. What Does Er dH Mean on an LG Refrigerator? LG refrigerators run […]
~55%
DIY Fixable
From $150
Typical Repair Cost
1–3 hours
Pro Repair Time
Quick Assessment
Answer to continue safely
Is it safe to keep using?
Maybe. The refrigerator may continue cooling until frost completely blocks the evaporator coils. You have a window of days to a week before complete cooling failure. Minimize door openings and reduce stored food to limit spoilage risk.
Can I reset the code?
Yes. A power reset will not fix a failed heater or thermal fuse. Manual defrosting is a temporary workaround but the heater component must be replaced to resolve the error permanently.
When to stop immediately?
Stop if you notice: Freezer temperature rises above 10°F and frozen food is thawing, Water is leaking inside or under the refrigerator from melting ice.
Symptoms You May Notice
Thick Frost Layer Visible on Freezer Back Wall
A heavy layer of ice or frost is visible on the rear interior wall of the freezer or when the evaporator cover is removed. This frost buildup indicates defrost cycles have not been completing successfully for days or weeks.
Freezer Cooling Weakens Progressively
Freezer temperatures gradually rise over several days as frost accumulation insulates the evaporator coils and blocks airflow. Food begins to thaw slowly, and the unit runs constantly without achieving target temperature.
Water Pooling Under the Refrigerator
As frost eventually melts from ambient heat (when the evaporator is completely blocked), water overwhelms the drain and pools under or inside the refrigerator. This is a late-stage symptom indicating prolonged defrost failure.
Ice buildup inside the unit
Frost or ice accumulates on interior walls or around components because the defrost cycle cannot complete, restricting airflow and reducing efficiency.
Possible Causes
Failed Defrost Heater Element
The resistance wire or glass-encased heating element that heats the evaporator coils has burned out, creating an open circuit. A continuity test across the heater terminals will show no continuity when failed.
Requires ProfessionalBlown Defrost Thermostat (Thermal Fuse)
The defrost thermostat is a one-time-use thermal fuse that opens permanently if the evaporator temperature ever exceeds its rating. Once open, it cuts power to the heater and must be replaced. It cannot be reset.
Requires ProfessionalDefrost Control Board Relay Failure
The relay on the main control board that switches power to the defrost heater can fail in the open position, preventing the heater from ever receiving power during the defrost cycle.
Requires ProfessionalSafe Checks You Can Do
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1
Perform a Manual Forced Defrost
On most LG models, hold the Refrigerator and Ice Plus buttons simultaneously for 5 seconds to enter diagnostic mode, then press the Refrigerator button to cycle to the defrost function. The unit will attempt a defrost cycle. Listen for a hissing or clicking sound from the freezer, which indicates the heater is activating. No sound at all points to heater or thermostat failure.
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2
Manually Defrost by Unplugging
Unplug the refrigerator and leave both doors open for 24–48 hours. This melts all accumulated frost even without the heater. If cooling returns to normal temporarily after this defrost but the Er dH code comes back within a week, the heater or thermostat needs replacement.
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3
Check Freezer Rear Wall for Frost Buildup
With the freezer empty, press on the rear interior wall. If it feels like a solid block of ice rather than a flat plastic panel, or if there is visible frost more than half an inch thick, the defrost system has been failing for an extended period.
When to Call a Professional
Contact a qualified technician if:
- Defrost heater element shows no continuity on multimeter test
- Defrost thermostat shows no continuity at room temperature (should have continuity when cold)
- Both heater and thermostat test good but forced defrost cycle still fails
Need Professional Help?
Find qualified technicians in your area for proper diagnostics and repair.
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