07/2009 - Art. Nr. 13 022 182A
21
Troubleshooting
Fuel oil operation
Malfunction diagnosis and repair
In the event of a malfunction, first check
that the prerequisites for correct
operation are fulfilled:
1.
Is there any current?
2.
Is there fuel oil in the tank?
3.
Are all shut-off valves open?
4.
Are all control and safety devices,
such as the boiler thermostat, low
water detector, limit switches, etc.
correctly set?
If the malfunction is still present, refer to
the table below.
Important safety components must not
be repaired; these components must be
replaced by parts with the same part
number.
Only use original spare parts.
Switch off the power supply
before carrying out
maintenance or cleaning.
Note:
After any work on the system:
• Under normal operating conditions
(doors closed, cover fitted, etc.),
check combustion and check the
individual lines for leaks.
• Record the results in the relevant
documents.
Observation
Cause
Corrective action
The thermostat no longer starts the
burner.
No heat requested by thermostats
Defective control unit.
Check/replace the thermostat.
Replace the control unit.
The burner starts up briefly when
the power supply is switched on and
then stops
Control unit has been locked
intentionally
Unlock the unit.
The burner starts then stops after
pre-ventilation
Unauthorised flame is detected
during the pre-ventilation/pre-
ignition period
Check for the ignition spark/adjust the electrodes/replace
Check/replace the fuel oil solenoid valve
The burner starts and stops after the
solenoid valves have opened
No flame at the end of the safety
time.
Check fuel oil level in tank.
Top tank up as required.
Open the valves.
Check the fuel oil pressure and the operation of the pump,
coupling, filter and solenoid valve.
Check the ignition circuit, the electrodes and their settings.
Clean the electrodes.
Clean/replace the flame detection cell.
Replace the following items as required:
ignition electrodes/ignition cables/igniter/nozzle/pump/
solenoid valve/control unit.
Flame failure during operation.
The flame goes out during operation
en
Summary of Contents for NC12 B117
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