Immerse the thermostat in water and gradually heat water.

Check the valve opening temperature.

Valve opening temperature : 82°C (177°F)

Full opening temperature : 95°C (205°F)

If the valve opening temperature is not as specified, replace the thermostat.

Check the valve lift.

Valve lift : Min. 10mm (0.4in.) at 95°C (205°F)

If the valve lift is not as specified, replace the thermostat.