The wash heater is at the bottom of the tub where it heats the water in the sump. On Tru-Steam® models, it also boils the water in the sump to make steam. Check the voltage to the wash heater by putting your voltmeter on the heater terminals and measuring the voltage, which should be approximately 120 VAC when operating. This voltage can also be measured at the heater's connector on the main board. There is a point in TEST MODE that activates the wash heater for 1.5 seconds, so have the meter connected before pressing the test button. With the heater disconnected from the circuit, it should read 15 ohms ± 20%.

To remove the heater, first drain the sump. Disconnect the electric terminals. Remove the outer nut that holds the ground wire to the center post. Unscrew the second nut on the ground post all the way to the end but do not remove it. This will remove the tension on the gasket and allow the heater to be pulled out. If a foreign object becomes caught between the drum and tub, it can sometimes be removed through the heater opening using a hooked wire after removing the heater.

The wash heater thermistor can be tested at its connector or at the connector on the main board. Its rubber gasket is a pressure fit in the hole next to the heater. See the section on thermistors. The round object on the right is the ECO. This is the sensor that determines water hardness and detergent concentration. This works in conjunction with the wash optimizer, which helps determine water levels and numbers of rinses needed. Do NOT confuse the two, and their functions are entirely different. NOTE! Older models had a thermistor that was not a part of the heater assembly. The thermistor mounted in the hole occupied by the ECO sensor on newer models. If replacing a heater assembly with one that has the thermistor included, the wiring harness will not reach. The official LG Factory repair method is to replace the wiring harness when replacing the heater with the newer style. Most people will use a couple of short pieces of wire, crimp connectors, and heat shrink tubing to effect the repair. The thermistor is not polarity sensitive, so it doesn't matter which wire connects to which terminal on the thermistor. LEAVE THE ORIGINAL THERMISTOR IN THE RUBBER GROMMET! It will keep water from leaking there. It is now disconnected and will not affect the operation of the machine.

This photo shows the heater element in its holder in the sump of the tub. Insert it carefully and tighten to prevent leaks.

Questions? Comments! Concerns? Report an error?
Let us know!
An e-mail should solve the problem.

© 2017 Reliable Parts