What this error means
Heater error — the dishwasher is not reaching or maintaining the correct wash temperature
The HE error on an LG dishwasher means the machine has failed to heat the water to the required temperature within the allowed time, or the temperature sensor has returned an out-of-range reading. The most common causes are a failed heating element, a faulty NTC thermistor temperature sensor, or heavy limescale coating the element. A wiring fault to either component can also produce HE.
What you'll need first
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Step-by-step
Symptoms to look for
- Dishes coming out cold, greasy, or with undissolved detergent after a hot programme
- Interior of the dishwasher feels no warmer than room temperature during a cycle
- HE displayed partway through a wash or rinse programme
- Programme runs significantly longer than the displayed time before faulting
Diagnostic steps
Unplug for 5 minutes to reset the board. Plug back in and run the hottest available programme — Intensive or 70 degrees — with no load. After 15 minutes, carefully open the door a few centimetres. You should feel warm to hot steam escaping immediately. If the interior is no warmer than room temperature, the element is not heating at all.
Add a proprietary dishwasher descaler or two tablespoons of citric acid to the base of the tub and run a full 65-degree empty cycle. Limescale on the element surface acts as insulation — the element can draw full power while transferring very little heat to the water. This is the most common cause of gradual heating performance loss before HE appears as a consistent fault.
Open the salt cap on the tub floor. If empty or very low, top up with coarse dishwasher salt (not table salt). The built-in water softener uses salt to prevent limescale forming on the element and spray arms.
With the dishwasher completely unplugged, remove the lower basket. The heating element is the metal bar or ring running across the base of the tub. Check for cracks, orange corrosion patches, or sections where the coating has burnt away.
With the dishwasher unplugged, remove the lower kickplate panel. The element terminals are accessible from beneath. Disconnect the wiring and test across both terminals with a multimeter. A healthy LG dishwasher element reads between 20 and 30 ohms. A reading of zero (short circuit) or OL (open circuit) means the element has failed.
The NTC sensor is mounted in the sump or near the tub base, connected by two thin wires. Disconnect its connector and test across the terminals with a multimeter. At room temperature a healthy LG dishwasher NTC reads between 4,000 and 12,000 ohms. A zero or OL reading means the sensor has failed.
When to call an engineer
- Heating element reads outside 20 to 30 ohms or shows continuity to earth — must be replaced
- NTC thermistor reads open circuit or zero ohms on a multimeter
- Element tests within normal range but HE persists — wiring or control board fault
- Visible corrosion, cracking, or burnt sections on the element surface in the tub base
Frequently asked questions
What is the NTC thermistor and why does it cause HE?
Can limescale alone cause HE without the element being broken?
Are dishes safe after a cycle that triggered HE?
How do I tell whether it is the element or the thermistor that has failed?
🎯 What is likely causing this fault?
⚠️ Estimates based on common faults — not a guaranteed diagnosis. Always verify before ordering parts.
Parts you may need
Enter your model number to filter results to your exact machine
Usually found on a label inside the door frame or on the back panel of the machine.
| Part | Approx. UK Cost | Find it |
|---|---|---|
| Heating element | £15 - £20 | 🏷️ eBay UK → |
| Heating element | £15 - £20 | 🛒 Amazon UK → |
| NTC Thermistor | £10 - £20 | 🏷️ eBay UK → |
ℹ️ Prices are approximate. Always check the part number matches your model before ordering. Not sure of your model number? Find out how to locate it here.