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pressure of the water that goes to the heating tube coil. When the machine is not
set to deliver the maximum pressure, the extra pressure runs back to the waterin-
letpipe through a return mains. For example when low pressure is needed, or
when the start/ stop trigger is not squeezed when the machine is running.
In the heating tube coil, the water is heated by an oilburner. A thermostat (No. 3)
placed at the end of the tube coil, constantly checks the watertemperature and
compares this to the temperature which has been set at the thermostat at the front
of the machine. When temperature is too low, the burner starts, when the water
has reached it's temperature, the burner stops.
The tube coil is two times protected agains overheating:
1.
thermostat knob (No. 3): when the right temperature is reached, the fuel circuit
is closed by an electric valve.
2.
microswitch: this switch is set to the pressure regulator. When the pressure is
set too low, (less then aprox. 30 bar/420 psi) the microswitch closes the fuel
circuit by an electric valve.
The oilburner operates as follows: The burnermotor controls both airfan and fuel
pump. By means of an electric valve, the fuel is pumped into the burner. Here the
fuel gets vaporized and set to fire by two sparks. To achieve a high efficiency level,
the flames and hot smoke gasses are blown through the tube coil to an optimum.
This causes a minimum of lost heat through the funnel. Ignition is continuously, so
that hardly any smoke occurs at starting the burner.
If the machine runs out of fuel, this is indicated by a pilot lamp (does not apply to
the HD 600-100).
8.0 POSSIBILITIES OF FAILURE
1 Machine does not function:
*
blown fuse
- renew fuse.
*
thermal failure
- turn on the main switch (No. 1) (if it fails
repeatedly: see point 2).
2 Thermal relay (main switch) keeps failing:
*
blown fuse
- renew.
*
pressure too high
- lower pressure, clean nozzle.
*
too low tension current
- remove too thin or too long extension cords.
*
defective motor
- replace or repair.
3 The burner does not work:
*
thermostat not on
- switch on (No. 3).