HDS Middle Range / HDS Premium Range
Unit Function
Service Manual 04.2008
Page 11 / 127
2.1
Control panel
Functions of the LED displays in operating mode
Symbol
Activity
Meaning / Action
1 x flashing
LED No.
0
2 x flashing
3 x flashing
4 x flashing
1 x flashing
light up
1
1 x flashing
2
light up
3
light up
4
1 x flashing
5
2 x flashing
3 x flashing
4 x flashing
1 x flashing
6
2 x flashing
3 x flashing
light up
7
Insufficient oil. Check/top up the oil level of the high-pressure
pump.
Leakage. Check high-pressure system for leaks.
Dry running. Check water inlet/ensure water supply.
Reed switch sticks. Check safety block/repair reed switch.
Motor rotates in the wrong direction. Switch off the unit and
rotate the phase inverter in the unit plug through 180°.
Unit is ready for operation.
Unit was either in continuous operation for 30 minutes or
was in standby operation for 30 minutes.
Fuel tank is empty. Add more fuel.
Cleaning agent tank 1 is empty. Add more cleaning agent
(HDS 12/18 only).
Fault in the motor contactor (motor current below 1.5 A for
3 seconds although contactor connected). Check/replace
contactor.
Motor thermal contact is open/defective. Determine/remove
cause. Replace the motor
Current asymmetry or undervoltage or overvoltage. Check
mains connection.
Current consumption too high. Check mechanics for
resistance. Check mains connection.
Exhaust thermostat is open. Check exhaust temperature/
replace thermostat. Perform burner maintenance.
.
Flame sensor signals burner fault. Clean and check burner,
ignition and fuel system.
RFID read-write electronics are defective - replace.
Service work is due.
4 x flashing
Temperature sensor fault. Cable break (temperature below
-5 °C, although burner is on) or short-circuit (temperature
above 220 °C for a lengthy period).