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Thermostat: Testing and Inspection

Thermostat Test

Replace the thermostat if it is in the open position at room temperature.

To test a closed thermostat:

1. Suspend the thermostat (A) in a container of water. Do not let the thermometer (B) touch the bottom of the hot container.





2. Heat the water, and check the temperature with the thermometer. Check the temperature at which the thermostat first opens, and at which it is fully open.
3. Measure the lift height of the thermostat when it is fully open.

Standard Thermostat
Lift Height: Above 8.0 mm (0.31 in.)
Starts Opening: 169 - 176°F (76 - 80°C)
Fully Open: 194°F (90°C)