Thermostat: Testing and Inspection

1. Inspect thermostat.

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

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





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





(c) Check the valve lift.
Valve lift: 10.0 mm (0.394 inch) or more at 95° C (203° F)
If the valve lift is not as specified, replace the thermostat.
(d) 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.