How to Test Dryer Thermostats That Overheat With a Continuity Tester

Several different parts might cause a dryer to overheat. Determining how to test a dryer thermostat that overheats is the first step in analyzing the problem. Newer dryers have a thermal-fuse or hi-limit thermostat that will shut the heating element off if the dryer gets too hot. Most overheating problems are the result of a bad heating element, not the thermostat.

Things You'll Need

• Screwdriver
• Needle nose pliers
• Continuity tester

Instructions

1. Disconnect the dryer from the electrical supply by unplugging it from the wall outlet. Move the dryer away from the wall so that you can access the rear of the dryer.

2. Remove the rear panel of the dryer. Use a screwdriver to remove the securing screws, and place the rear panel out of the way.

3. Locate the can that holds the heating element. The high-limit thermostat and the cycling thermostat are located on the side of the can.

4. Remove the two wires that are connected to the thermostat. Use a pair of needle nose pliers, and grasp the wire at the lead to pull them off the terminals.

5. Set the continuity tester scale to the RX1 position. Touch one probe to each terminal on the thermostat. A reading of zero should be present. Any other reading, and the thermostat needs to be replaced. If the reading is good, proceed to the hi-limit thermostat.

6. Reconnect the wires to the cycling thermostat by pushing the leads back over the terminals.

7. Disconnect the wires from the hi-limit thermostat just as you did for the cycling thermostat. Zero the continuity tester, and test the thermostat. Any reading other than zero indicates a need to replace the thermostat.

8. Test the heating element if both thermostats test correctly. Dryers will most often overheat due to a heating element grounding out.

9. Remove the wires from the heating element, and lift the heating element out of the can.

10. Touch a probe to each of the heating element terminals. If you receive back a reading of infinite resistance, the heating element needs to be replaced.

Tips & Warnings

• Always unplug electrical appliances before attempting repairs or service.

References

• Part Select: Test Dryer Thermostat
• Tpub: Test Hi-Limit Thermostat
• Part Select: Test Heating Element

Resources

• Meter Testing