LG Refrigerators DH Error Code (Defrost Heater Issue): How to Fix It Yourself
The DH error on an LG fridge means the defrost cycle is not working correctly. Every fridge periodically heats up its evaporator coils to melt frost buildup. When the defrost heater fails, ice builds up on the coils, blocks airflow, and the fridge stops cooling properly. You may also notice frost or ice inside the freezer compartment.
⚠️ Safety First
- Unplug the refrigerator before working inside the freezer.
- Transfer perishable food to a cooler with ice packs.
- The defrost heater operates at high temperatures — let it cool before handling.
Parts You May Need
Step-by-Step Repair
- 1
Unplug the fridge and clear out the freezer
Disconnect the power cord. Remove all food from the freezer and store it in a cooler. Remove any shelves, drawers, or ice trays that are in the way of the back panel.
- 2
Remove the freezer back panel
Unscrew the rear panel inside the freezer compartment. There are usually 6-10 screws. Gently pry it forward. Behind it you will see the evaporator coils and the defrost heater, which is a glass tube or metal rod running along the bottom of the coils.
- 3
Melt any ice buildup
If the coils are covered in a thick sheet of ice, use a hair dryer on medium heat to carefully melt it. Lay towels at the bottom to catch the water. Do not use anything sharp to chip the ice — you could damage the coils or puncture a refrigerant line. This step can take 15-20 minutes.
- 4
Test the defrost heater
Once the ice is cleared, disconnect the wires from the defrost heater. Set your multimeter to continuity mode and test across the heater terminals. If you get no reading (open circuit), the heater is burned out and needs replacing. If you do get continuity, the heater is fine and the problem may be the defrost thermostat or control board.
- 5
Replace and reassemble
If the heater tested bad, unclip or unscrew it and install the replacement. Reconnect the wires, put the back panel on, and reinstall the shelves. Plug the fridge back in. It will take 12-24 hours to return to normal temperature. The DH code should clear automatically.
If That Didn't Work
- Faulty defrost thermostat (bi-metal)
- Failed defrost timer or control board relay
- Wiring break between the control board and the heater
When to Call a Professional
If the heater tests fine, the issue is likely the defrost thermostat or control board — diagnosing those requires more advanced testing. A technician can run the full defrost diagnostic for $100–$200. Total repair with parts is typically $150–$300.
Related Repairs
Disclaimer: This guide is for informational and educational purposes only and does not constitute professional repair advice. All repairs are performed at your own risk. RepairItFree.com is not liable for any personal injury, property damage, device damage, voided warranties, or other losses resulting from the use of this information.
If you are unsure about any step — especially anything involving electricity, gas, water, or refrigerant — stop and consult a qualified professional. Your safety is more important than saving money.
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