Unit Inspection

Suspected Cause	Correction
Inspect water pump impeller	Replace water pump
Inspect for foreign materials and status of thermostat valve	Inspect unit after removing foreign materials
Inspect for stuck thermostat valve Immerse thermostat in water heated to over 95°C (203°F), then heat for at least 3 minutes to check valve lift NOTE: Do not use water below 95°C (203°F) Do not directly heat unit as this will damage thermostat	Check valve lift - Replace thermostat if valve lift is below specification or valve is stuck