Kärcher HDS 9/50 De Tr1 Service Manual page 72

Mode of operation
The water from the high pressure pump enters the interior
heating coil spiral, is heated while flowing through and ex-
its to the bottom from the heating coil spiral.
The fuel is vaporised by the fuel nozzle and ignited by the
spark of the ignition electrodes.
The combustion air from the blower first flows through the
double-walled boiler exterior toward the top, then it flows
downward with the flame and is emitted as exhaust
through the exhaust stack toward the top into the atmos-
phere.
The boiler floor is made of fire-resistant insulating con-
crete. It prevents a radiation of the heat and is used to re-
route the flames.
The adjustment of the burner to good exhaust values is
achieved via the air flap on the blower (air volume) and
with the adjustment screw on the fuel pump (fuel pres-
sure).
The temperature increase with the full water volume is
max.:
with HDS 9/50: 56.5K
–
with HDS 13/35: 60.0K
–
with HDS 17/20: 52.5K
–
with HDS 13/20: 63.0K
–
When the water volume is reduced by the pressure and
volume regulation, the water can be heated to max. 95°C.
An optimal burner performance is only possible if the heat-
ing coil is neither full of soot nor other deposits.
Furthermore, the spark electrodes, the amount of fuel and
the amount of air must be adjusted properly.
72
English 5.906-736.0 Rev. 00 (07/15)