How Do Air Heaters Work
When the unit is switched on the dosing pump feeds fuel from the vehicle's fuel tank to the heater. Here the fuel is automatically ignited by means of a glow plug. If combustion does not occur immediately the unit automatically repeats the start-up procedure. In the combustion chamber a flame is lit which heats up the heat exchanger. The unit takes air in from outside of the vehicle for combustion purposes and the combusted exhaust air is discharged back outside. During heating, the integrated fan sucks in the air to be heated through the inlet and feeds it through the unit. As the air flows through the heat exchanger it is heated up and is then distributed through the outlet.
The connected hot air ducting spreads the air evenly throughout the vehicle interior. Due to the unit's separation of the combustion cycle from the heating cycle there is no quality impairment of the hot air. A temperature sensor constantly measures the interior temperature and adapts the heating level by automatically adjusting the amount of air passing through the unit. In this way, the temperature selected by the user is rapidly reached and maintained at a constant level. After the unit has been switched off, the combustion process is terminated in a controlled manner. For this purpose the unit briefly goes into re-run mode to cool itself down. It is then immediately ready for restarting.
The following image gives you a brief idea on what happens inside the air heater.
- Click picture to enlarge
