LG · Dishwasher
LG Dishwasher HE Error Code
Heater did not reach target temperature
What this error means
HE reports a heating error—the thermistor did not see water reach the programmed wash temperature within the heat window. On LG dishwashers this often traces to lukewarm house water rather than a dead element.
How HE is detected
When HE appears on a LG dishwasher, the control board has confirmed that water did not leave the machine within the programmed drain window. On LG LDP7808BD, LG LDP6797ST, and similar variants, the drain pump runs for a fixed interval—often three to seven minutes on washers and dishwashers—while a pressure switch or turbidity sensor verifies the tub or sump is empty. If water remains, the cycle stops to prevent spin with a full tub or overflow on the next fill.
Most HE calls are resolved without parts: run the kitchen faucet until hot before starting a cycle. Restricted drain paths mimic pump failure because the impeller spins against a blocked hose or filter. Document whether the pump hums audibly during the drain step; a humming pump with no water movement points to a clogged filter or kinked hose, while silence may indicate a failed pump motor or loose wiring at the harness.
After clearing blockages, run a short cycle and listen at the drain hose for steady water flow. If HE returns on the next load with a clean filter and straight hose, measure resistance at the pump motor connector per the service manual for your model before ordering a replacement pump assembly.
Common causes
- Household water heater set below 120°F
- Running hot water elsewhere during fill
- Open heating element or blown thermal limit
- Faulty thermistor reporting false cold readings
Step-by-step fixes
- 1Run the kitchen faucet until hot before starting a cycle
- 2Select a high-temp or sanitize option and feel the door glass mid-wash for warmth
- 3Confirm the dishwasher is connected to hot water, not cold-only plumbing
- 4Retry after ensuring the water heater recovered from prior use
When to call a technician
If water stays cold through a sanitize cycle with verified hot supply, the element or thermistor needs bench testing.
Affected models
- LG LDP7808BD
- LG LDP6797ST
- LG LDTS5552S
Prevention & maintenance
- Clean drain filters and hose terminations monthly on high-use dishwashers to prevent HE from lint and food debris buildup.
- Record when HE appears in the cycle and whether it clears after a 60-second power reset on your LG dishwasher—that detail speeds diagnosis if you call service.
- Keep the model and serial number from the rating plate when ordering parts for HE; LG uses multiple revisions with different harness lengths and board firmware.
- Photograph wiring connector orientation before disconnecting any component while troubleshooting HE; reversed plugs on pumps and valves cause immediate repeat faults.