What Causes a Diesel Heater to Fail to Ignite?
1 Answers
Vehicle diesel heaters fail to ignite due to thermostat issues, water pump impeller failure, or engine cooling system malfunctions. Below is a detailed analysis of these problems: Thermostat Issues: If the thermostat is stuck open or opens too early, the cooling system prematurely enters a large circulation cycle. When the external temperature is very low, especially while driving, cold air quickly cools the antifreeze, preventing the engine water temperature from rising and resulting in no warm air. Water Pump Impeller Failure: A damaged or slipping water pump impeller reduces the flow rate through the heater core, preventing sufficient heat transfer. Engine Cooling System Malfunction: Air pockets in the engine cooling system can disrupt circulation, leading to high water temperature and ineffective heating. If air constantly enters the cooling system, it may indicate a damaged cylinder head gasket allowing gas into the system. If the inlet pipe of the heater core is hot while the outlet pipe remains cool, the heater core is likely clogged and requires replacement.