English
Fault
Unit does not start up,
indicator light "F" does
not illuminate
+ indicator light (G)
illuminates
Burner does
not ignite or
flame extinguishes
during operation
Flame monitoring
system fault display
(E) lights up
i
Important!
Note!
Switch unit on and off
to unlock the flame
monitoring system
E1
E. Troubleshooting
Possible cause
No power supply to unit.
Safety timer functioning.
Fuse in control circuit (F3)
has burnt out. Fuse is housed
in the control circuit
transformer (T2).
Pressure switch HD or ND
defective.
Timer module (A1) defective.
Thermal sensor (WS) in the
motor or overload
circuit-breaker (F1) has
tripped.
Temperature regulator (B)
set too low.
Unit switch not set to burner.
Water level sensor has
switched off.
Fuel tank empty.
Fuel filter blocked.
Photocell for flame
monitoring system incorrectly
aligned or defective.
No ignition spark (can be
ascertained through the
inspection glass in the burner
cover).
Burner motor is blocked.
Fuel pump or fuel solenoid
valve defective.
Remedy
Check power supply.
Briefly switch off unit with unit switch,
then switch on again.
Insert new fuse; if it blows again,
eliminate cause of overload.
Check pressure switch.
Check connections; if required, replace.
Eliminate cause of overload.
Set temperature regulator higher.
Switch on burner.
Ensure adequate water supply
(at least 1300 l/h). Check unit for leaks.
Clean strainer on the water level sensor.
Fill up with fuel.
Clean fuel filter:
– Unscrew fuel filter,
– Clean fuel filter,
– Screw in fuel filter.
Check that the photocell is correctly
seated.
Check the gap between the electrodes on
the ignition transformer and ignition cable.
Correct the gap or replace defective parts.
If required, clean.
Remove blockage. Remove plug (H)
from the instrument panel and unlock
the overflow circuit-breaker.
Re-insert the plug.
Check and replace defective parts.
5.959-742 A 2009651 (11/04)
HDS 891 / 1291 ST
By whom
Electrician
Operator
Customer
service
Customer
service
Customer
service
Customer
service
Operator
Operator
Operator
Operator
Operator
Operator
Customer
service
Customer
service
Operator