What does LG dishwasher error code HE1 mean?

The HE1 code means the dishwasher's water is not reaching the programmed temperature. Check that your hot water heater is set to at least 120 °F and run hot water at the sink before starting the dishwasher. If the code persists, the heating element or NTC thermistor may have failed and will need professional testing.

HE1

LG Dishwasher Error Code HE1 — Heating Element / NTC Thermistor Fault

Professional Repair 45–75 minutes (professional) Tools: Multimeter, Phillips screwdriver, T15 Torx screwdriver

What this means

The HE1 error code on LG dishwashers indicates a fault in the water heating system. The dishwasher's NTC (negative temperature coefficient) thermistor is detecting that the water is not reaching the programmed temperature, or the thermistor itself is returning abnormal resistance values. This can be caused by a failed heating element, a burned-out NTC thermistor, a wiring issue between the heater and the control board, or a faulty control board relay that controls the heater. Without proper heating, the dishwasher cannot sanitize dishes or dissolve detergent effectively, resulting in poor cleaning performance. On LG QuadWash models, inadequate heating can also affect the performance of the high-pressure spray arms that rely on hot water for grease removal.

Alternate codes: HE 1

Step-by-step fix

4 steps

Verify the water supply temperature

Check your home's hot water heater setting. LG recommends the incoming hot water supply be set to at least 120 °F (49 °C). If the incoming water is too cold, the dishwasher heater may be unable to reach the programmed cycle temperature within the allotted time.

Run the kitchen hot water faucet for 1–2 minutes before starting the dishwasher to flush cold water from the line.

Power-reset the dishwasher

Turn off the circuit breaker for 1 minute, then restore power. Run a normal cycle to see if HE1 returns. A temporary control board glitch can cause a one-time false code.

If the dishwasher completes the cycle without the code returning, the issue was likely a temporary sensor misread.

Test the NTC thermistor

Unplug the dishwasher and locate the NTC thermistor (usually attached to the sump or near the heating element). Disconnect it and test with a multimeter. At room temperature (~75 °F), it should read approximately 10,000–12,000 ohms. A wildly different reading indicates failure.

The NTC resistance decreases as temperature increases. If it reads very low at room temperature, it is shorted internally.

Test the heating element

With the dishwasher unplugged, disconnect the heating element leads and test for continuity and resistance. A typical LG dishwasher heating element reads approximately 12–25 ohms. An OL reading means the element has burned out. Also test between each terminal and ground — any continuity indicates a ground fault.

The heating element is located in the sump area at the bottom of the dishwasher tub.

When to call a professional

If the NTC thermistor and heating element both test within spec, the control board's heater relay may be faulty. A technician should perform live voltage testing to determine if the board is sending power to the heater during the cycle.

Related error codes

The dishwasher's water heating element is not working.

Advanced Fix · 30–60 minutes

The dishwasher's temperature sensor (thermistor) is malfunctioning.

Moderate Fix · 20–40 minutes

Information compiled from manufacturer service manuals, official troubleshooting documentation, and appliance repair industry resources. This guide is for informational purposes only — always consult a qualified technician for complex repairs.

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