Operation Manual

8.
COMMON PROBLEMS AND FAULT CODES
8.1
Common
problems
Hot water temperature at the taps is reduced. This may be because the temperature
of
the mains cold water supply is colder during the winter period.
The gas supply to the boiler has run out,
or
is
about to run out. Near empty propane
gas bottles will supply enough gas to run low power appliances such as cookers and
gas fires, but will fail to supply high powered appliances such as the combination
boiler.
During busy periods, the mains cold water supply to the boiler may be subjected to
variations
in
pressure, this will result
in
fluctuations
in
the hot water temperature at
the hot water outlet.
If the mains power supply to the boiler has been interrupted
or
turned off, then the
time clock/programmer (if fitted) must be reset to the correct time, if the boiler is to
be operated
in
the timed sequence
in
central heating mode.
8.2 Fault
Codes
The Marco 24 CPM and 30 CPM Boilers have a self diagnostic system built into their
printed circuit board. Should a fault for safety related
or
other reasons occur, then the
boiler will failsafe by locking out, which
is
indicated by the
red
LED
on
the control panel.
The fault can be identified by the code
in
the LCD display. The electronic failsafe
is
also
backed by a mechanical means
of
protection, should the electronics fail to detect a fault.
These mechanical forms
of
protection will protect and ensure the safe shut down of the
boiler. The software protection built into the P.C.B. will
run
a system check
on
components
which are essential to the safe operation of the boiler. This occurs before any ignition
sequence takes place, if any component
is
found to
be
faulty or out of a predetermined
range, the boiler will lockout with the fault code displayed
on
the LCD screen. Each Fault
will comprise a number.
NOTE: The red LED stays on constantly until the reset button
is pressed.
Fault conditions can be divided
in
2 groups:
1. Lockout Conditions
Lockout flue gas over heat
Lockout boiler over heat
No flame signal
Flame loss
Flame simulation
Failure flow-return supervision
Failure gas valve circuit
V1N2
Failure fan speed
34