Thermostat: Testing and Inspection

OPENING TEMPERATURE

NOTE: The thermostat is numbered with the valve, opening temperature.





1. Immerse the thermostat in water and gradually heat the water.
2. Check the valve opening temperature. Valve opening temperature: 80-84° C (176-183° F).
3. If the valve opening temperature is not as specified, replace the thermostat.





VALVE LIFT
1. Measure the valve lift.
Valve lift: At 95° C (203° F) 10 mm (0.39 inch) or more.
2. If the valve lift is not as specified, replace the thermostat.
3. Check that the valve is fully closed when the thermostat is at low temperatures (below 40° C (104° F)).
- If not closed, replace the thermostat.