01/2005 - Art. Nr. 13 010 553B
50
Troubleshooting
Defect
Causes
Remedies
The burner does not function.
Nothing happens.
Normal gas pressure
Thermostatic chain.
Too low gas pressure.
Gas pressure switch misadjusted or defective.
Foreign matter present in the pressure tap
channel
Thermostats defective or misadjusted.
Adjust the feed pressure.
Clean the filter.
Check the gas pressure switch or replace it.
Clean the pressure tap tubes (without
pressurised fluid).
Adjust the thermostats or replace them.
The burner does not start after closing of the
thermostatic circuit.
The control and safety unit does not indicate
any defect.
Supply voltage drop or absence.
Unit defective.
Check the origin of voltage drop or absence.
Replace the unit.
The burner starts when the voltage is applied
and functions during a short period of time,
then it stops and delivers this signal:
x x V y y y
-
y y y y y
The control and safety unit has been switched
off purposely.
Reset the unit.
Unit energised
y y V x x x
Air pressure switch: the contact is stuck.
Replace the pressure switch.
Unit energised
x x x V y y
x x x x V y
Air pressure switch: the contact does not
close.
Air pressure switch: the contact opens on
start-up or in service.
Check the pressure tap (foreign matter) and
the wiring.
Adjust the pressure switch or replace it.
Unit energised
x x V y y y
Stray light during prefiring.
Check tightness of the valve and/or replace it.
Unit energised
x V y y y y
No flame at the end of the safety time delay:
Unsuitable gas flow rate.
Flame monitoring circuit defective.
No firing arc:
Firing electrode(s) short-circuited.
Firing wire(s) damaged or defective.
Firing transformer defective.
Control and safety unit.
Electromagnetic valves do not open.
Valves mechanically jammed.
Adjust the gas flow rate.
Check the condition and position of the
ionisation probe relative to ground.
Check the condition and connections of the
ionisation circuit (cable and measuring bridge).
Adjust, clean or replace the electrode(s).
Connect or replace the firing wires.
Connect the cables or replace them.
Replace the transformer. Replace the control
unit.
Check the wiring between the unit, the
servomotor and the ground.
Check the coil or replace it.
Replace the valve.
Unit energised
y y y y V x
Flame extinguishing when in service
Check the ionisation probe circuit.
Check the control and safety unit or replace it.
In case of failure one must check:
·
that the voltage is ON,
·
the gas supply (valve pressure and
opening),
·
the control elements,
·
the switch position on the control
board.
If the failure persists:
·
Read the luminous signals delivered
by the control and safety unit and
their meaning on the table below.
Special appliances are available which
can be adapted on SG xxx units to
make it possible to understand any
other pieces of information provided by
the control and safety unit.
All the safety components must not be
repaired but only replaced by identical
components.
m
Use only
the manufacturer’s
original parts.
Remarks:
After work has been carried out one
must:
·
Check the combustion under
operating conditions (doors closed,
cover in position, etc.) and the
circuit tightness.
·
Record the results on the relevant
documents.
Summary of Contents for 13 009 306
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