User Manual

37
4000123944-2
Overheat thermostat reset button
Refer to Section 20.11 to locate the overheat thermostat
reset button.
Depress the button to reset.
9826
OVERHEAT
THERMOSTAT
RESET
BUTTON
Diagram 18.1
18 Fault Finding
Before trying to operate the boiler make sure that :
• All gas supply cocks are open and that the gas supply has
been purged of air.
• The heating system pressure is at least 1 bar.
• There is a permanent mains supply to the boiler and that the
polarity is correct.
• The fuse on the PCB is intact.
WARNING. Always isolate the boiler from the electrical
supply before carrying out any electrical replacement work.
Always check for gas soundness after any service work.
Should there be any doubt about the voltage supply to any of
the components, it is possible to carry out a simple electrical
test to ensure all is operational in that area.
IMPORTANT: On completion of the fault finding task which
has required the breaking or remaking of the electrical
connections, the continuity, polarity, short circuit and
resistance to earth checks must be repeated using a suitable
multimeter.
TYPE OF FAULT CHECK
No display on control panel • 230V supply
• PCB fuse
• Connection between PCBs
No domestic hot water • Loose connections on control board (PCB)
No central heating • Connections on air pressure switch (electrical or tubes)
(warning light of fault code disconnected
displayed on control panel) • Faulty control or interface board (PCB's)
• Water pressure, flashing pressure
• Shortage of air or gas
• Faulty temperature sensor
• Overheating