Method for starting the combustion operation of a fuel-powered vehicle heater

A method for starting the combustion operation of a fuel-powered vehicle heater, the vehicle heater including a combustion chamber assembly to be supplied with fuel and combustion air, a fuel conveying device for conveying fuel into a combustion chamber of the combustion chamber assembly, a combustion air conveying device for conveying combustion air into the combustion chamber, wherein the combustion air conveying device includes at least one impeller wheel configured to be driven for rotation for conveying combustion air, the method comprising:

• a) in an ignition phase after generating a start command for starting the combustion operation, operating the combustion air conveying device for conveying combustion air into the combustion chamber at an ignition phase speed assigned to the ignition phase, and operating the fuel conveying device for conveying fuel into the combustion chamber at an ignition phase delivery rate assigned to the ignition phase for providing an ignitable fuel/combustion air mixture;
• b) in a first speed adaptation phase following the ignition phase, changing a speed of the combustion air conveying device to a flame stabilization phase speed which does not lead to the generation of a combustion resonance in the combustion chamber assembly;
• c) in a flame stabilization phase following the first speed adaptation phase, operating the combustion air conveying device at the flame stabilization phase speed;
• d) in a second speed adaptation phase following the flame stabilization phase, reducing the speed of the combustion air conveying device to a combustion operation speed;
• and,
• e) in combustion operation following the second speed adaptation phase, operating the combustion air conveying device at the combustion operation speed.