Thermostat: Testing and Inspection
THERMOSTATINSPECTION
1. INSPECT THERMOSTAT
a. Inspect the thermostat
HINT: The valve opening temperature is stamped on the thermostat.
b. Immerse the thermostat in water and gradually heat the water.
c. Check the valve opening temperature.
Valve opening temperature: 80 to 84°C (176 to 183°F)
If the valve opening temperature is not as specified, replace the thermostat.
d. Check the valve lift.
Valve lift: 10 mm (0.39 inch) or more at 95°C (203°F)
If the valve lift is not as specified, replace the thermostat.
e. Check that the valve is fully closed when the thermostat is at low temperatures (below 77°C (171°F)).
If not closed, replace the thermostat.