Thermostat: Testing and Inspection
THERMOSTATINSPECTION
1. INSPECT THERMOSTAT
HINT: 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 of the thermostat.
Valve opening temperature: 80 to 84°C (176 to 183°F)
HINT: If the valve opening temperature is not as specified, replace the thermostat.
c. Check the valve lift.
Valve lift: 10 mm (0.394 inch) or more at 95°C (203°F).
HINT: If the valve lift is not as specified, replace the thermostat.
d. Check that the valve is fully closed when the thermostat temperature is low (below 77°C (171°F)).
HINT: If not closed, replace the thermostat.