LG Dishwasher Not Heating: What Can You Do?

If your lg dishwasher not heating water, then the following internal parts may be to blame: heating elements, sensors, control module

LG dishwasher not heating

Checking temperature sensor and heating elements

Thermal sensor might be checked both with the help of a specialized diagnostic tool and visually. Pay attention to the condition of pins and wires. They should not be burnt or melted.

Use a special tool called multimeter for diagnosing the heater and the temperature sensor.

If you want to check the heater, set the tool in the ohmmeter mode. Pre-calculate the resistance of your heater. To do this, simply divide 48,400 by the power of your heating element indicated in user’s manual.

In the next step, disconnect the device from power supply, get access to the heating element and disconnect the wires, put the tester probes to the heating element terminals. If the value on the display is almost identical to the one you have previously calculated (in our case it was 17.29 Ohms), the element is fine. If it shows 0,1 or indefinite value – the heater has failed and needs to be replaced.

Modern models are often equipped with thermistor which is used as a temperature sensor. This element changes its resistance depending on the temperature. To check this element, set the tester in ohmmeter mode and after connecting to its contacts measure the resistance. Take a pot with a boiling water and place thermal sensor in it – the resistance should significantly increase, if not – the sensor is defective.

Faulty heating element

Manufacturers strongly recommend to add water softener at each wash cycle. If you don’t do that, the heating element will quickly get covered with scale. In addition, the heating element can fail for other reasons such as a spiral burnout or a breakdown of internal insulation (in this case the dishwasher will electrocute).

The heating unit of the dishwasher looks like a cylindrical case with taps for connecting sensors and pipes. The internal parts of the device are protected by a plastic case. If you do not know whether your unit may be dismantled or not, you should inspect it. If you see fasteners on the plastic case, it means that you will be able to disassemble it and replace the heating element alone, if not – you will have to replace the whole unit.

How to replace the heating element in the dishwasher

Okay, let’s start.

  1. Open the dishwasher door and pull out the rack, lay a cloth which absorbs water on the floor in order to protect its surface from moisture.
  2. Disconnect the dishwasher from the power supply, wait for 10–15 minutes (to let the condenser get discharged and protect yourself against electric shock).
  3. Disconnect all hoses.
  4. Find the plastic impeller inside the dishwasher and pull it up to remove.
  5. Pull out the filter.
  6. Remove the nuts holding the hose and the heating unit.
  7. After that, turn the dishwasher upside down.
  8. Depending on the particular model, remove the back cover or pull out the bottom panel (if we are talking about the embedded type of appliance). To remove the bottom panel, disconnect the heating unit from the drain hose and gently pull the panel towards you. At the same time, you will not be able to pull out the panel completely, since you will need to unscrew the fasteners inside the dishwasher itself.
  9. The heater is connected to the drain pump. Take the pump and rotate it clockwise half a turn. After that, pull the pump to the side – it will stay in your hands. After that, unscrew the temperature sensor.
  10. At the bottom, the heater is fixed with rubber fasteners. To remove it, you will need to put your hand under the unit.
  11. Disconnect the fittings and sensors, remove the burnt heater and replace it with a new one.

After that put all the parts back in the reverse order.