Thermostatic Valve

Disconnect thermostatic valve hoses. Blow through valve. Valve should be closed when temperature is below 110°F (43°C) with on-off and two-port systems and 68°F (20°C) on 900 models and 86°F (30°C) on 9000 model with proportional systems. Valve should be open when engine temperature is above that listed. Replace thermostatic valve if defective.