CONTROL METHOD FOR THE STARTUP FUNCTION OF A HEATING DEVICE WHICH USES FUEL

In a control method for the switch-on function sequence of a fuel-operated heating device, this comprises the following time periods: a pre-run phase (VPh) beginning with the switching on of the heating device, during which only outside air but no fuel is supplied to the combustor chamber for purging and which is ended after a predeterminable time period by the start (S) of combustion, a transition phase (ÜPh) immediately following the start (S) of combustion, and a settled steady operating state (BBZ) following the transition phase (ÜPh), during which an air mass with a value m Lnormal required for achieving the target lambda value and a corresponding fuel quantity are supplied to the combustor chamber. To improve the exhaust gas emission of such a heating device, it is provided that a reduced air mass is supplied to the combustor chamber at least during a portion of the transition phase (ÜPh), whose value m LÜbergang is smaller than the value m Lnormal of the air mass supplied to the combustor chamber during the settled steady operating state (BBZ).