LG WM0742H Series Training Manual page 49

TRAINING MANUAL WM0742HGA
The steam generator heater is shown on the previous page. The heater operates on
120 V @ 1,100 Watts. The amperage is approximately 9 amps. The wiring shows a
AC
gray wire (L1) and a red wire (Neutral.)
When STEAM is selected or a TUB CLEAN cycle is selected, the control board will verify
a high water level, add water via the cold valve if needed, and then energize the heater.
After several minutes steam is produced.
Serviceability is limited to testing component functions and available voltages or
amperages. If any component fails, the steam generator must be replaced as an assembly.
The thermistor is a NTC (Negative Temperature Coefficient) device; as temperature goes
up, resistance goes down. The ohm value at room temperature is approximately 60KΩ
and the voltage measured across the sensor is approximately 3.6 V At 212º the ohm
DC.
value is approximately 3.3 KΩ and the voltage measured across the sensor is 0.88 V
DC.
In the test mode, the heater will be ON for 1.5 seconds and the temperature for the
steam generator will be displayed in degrees Celsius. While in the test mode, with the
thermistor open or disconnected, the heater will not heat and the display will show 0. In
a steam cycle, the heater will be OFF if the sensor is open or disconnected.
WM0742HGA Page 47 TRAINING MANUAL