LG refrigerator Er dH means the defrost cycle exceeded 60 minutes without reaching target temperature. Manual defrost (unplug 8-24 hours, doors open) fixes most cases. If the error returns within 2-4 weeks, the defrost heater ($40-80) or defrost sensor ($25-50) needs replacement.
| Error Code | Er dH / Er dS |
|---|---|
| Meaning | Defrost timeout (dH) or defrost sensor failure (dS) |
| Difficulty | Easy to Moderate |
| Time to Fix | 8-24 hours (defrost) + testing |
| Tools Needed | Towels, Cooler, Multimeter (optional) |
| DIY Fixable | Yes |
| Official Source | LG Support |
Defrost errors occur when your refrigerator’s automatic defrost system can’t clear ice from the evaporator coils within the expected time. The first step is always manual defrost—more complex repairs are only needed if the error returns.
Understanding Defrost Errors
Er dH — Defrost Timeout
The refrigerator spent more than 60 minutes trying to defrost without reaching the target evaporator temperature. The defrost cycle should normally complete in 20-30 minutes.
Common causes:
- Excessive ice accumulation (most common)
- Defrost heater failure (burned-out element)
- Blown defrost temperature fuse
- Blocked drainage hole
- Main control board not activating heater properly
Er dS — Defrost Sensor Failure
The defrost sensor (thermistor) that monitors evaporator temperature has failed—either shorted or disconnected.
Variants: F dS (freezer defrost sensor), r dS (refrigerator defrost sensor)
Step 1: Manual Defrost Procedure
This resolves most defrost errors and should always be your first step.
Complete Manual Defrost
- Remove all food — Transfer to cooler with ice
- Unplug refrigerator — Complete power disconnection required
- Remove drawers and bins — Take out all removable parts
- Open both doors WIDE — Maximum airflow for fastest defrost
- Place towels — Inside freezer and on floor to catch water
- Wait 8-24 hours:
- Summer (warm room): 8-12 hours
- Winter (cold room): 1-3 days per LG
- Check drain hole — Center rear of freezer floor; clear with warm water if clogged
- Wipe completely dry — All surfaces before restarting
- Plug back in — Set temperatures: Refrigerator 37°F, Freezer 0°F
- Wait 24-48 hours — Allow temperatures to stabilize
Water drains through a hole at the rear of the freezer floor into a tray at the bottom back of the refrigerator. During defrost, this tray may overflow—have towels ready. The tray water normally evaporates from compressor heat during regular operation.
Step 2: Test Defrost Components
If Er dH returns within 2-4 weeks of manual defrost, the automatic defrost system has a failed component.
Accessing Defrost Components
- Unplug refrigerator
- Remove freezer contents
- Remove freezer drawers and ice bin
- Remove rear freezer panel (multiple screws)
- Defrost components are behind this panel near the evaporator coils
Testing Defrost Heater
The defrost heater is the long element behind the rear panel.
Test procedure:
- Disconnect heater wires
- Set multimeter to ohms (Ω)
- Touch probes to heater terminals
- Normal reading: 30-42Ω
- OL (infinite) reading: Heater is burned out—replace
Replacement cost: $40-80 for defrost heater assembly
Testing Defrost Thermistor (Sensor)
The thermistor monitors evaporator temperature to tell the control board when defrost is complete.
Test procedure:
- Disconnect thermistor wires
- Set multimeter to ohms
- Touch probes to thermistor terminals
- Normal reading at room temperature: ~11kΩ (11,000 ohms)
- Significantly different reading indicates failure
Replacement cost: $25-50 for defrost sensor with fuse
Testing Defrost Fuse
The thermal fuse is a safety device that blows if the evaporator gets too hot.
Test procedure:
- Disconnect fuse wires
- Set multimeter to continuity
- Touch probes to fuse terminals
- Good fuse: Beep (continuity present)
- Blown fuse: No beep (open circuit)—replace
The fuse is often sold as part of the defrost sensor assembly.
Why Defrost Systems Fail
Understanding causes helps prevent recurrence:
| Cause | Prevention |
|---|---|
| Door left open frequently | Minimize door openings |
| Damaged door gasket | Replace worn gaskets |
| Refrigerator not level | Adjust leveling feet |
| Blocked vents | Don’t pack food against vents |
| Failed defrost heater | Component replacement |
| Faulty control board | Professional diagnosis |
Component Replacement
Defrost Heater Replacement
- Unplug and access evaporator area
- Disconnect heater wire harness
- Remove mounting clips/screws
- Install new heater in same position
- Reconnect wiring
- Reassemble panels
Defrost Sensor Replacement
- Unplug and access evaporator area
- Locate sensor near top right of evaporator
- Cut zip ties holding sensor
- Disconnect wire harness from back wall
- Install new sensor, secure with new zip ties
- Reconnect wiring
- Reassemble
LG part numbers (verify for your model):
- Defrost sensor: #6615JB2005H, #6615JB2005N
- Defrost heater: Various by model
Model Coverage
Defrost errors appear on all LG refrigerator types:
- French Door: LRMVS, LRMVC, LRFXS series
- Side-by-Side: LRSXS, LRSVS series
- InstaView: All models
- Bottom/Top Freezer: Various models
When to Call a Tech
Contact a technician if:
- Manual defrost doesn’t resolve the error
- Error returns within days (not weeks)
- You’re not comfortable with component testing
- Heater and sensor test good but error persists (control board issue)
- Ice reforms rapidly after defrost
Sources
For official LG support: