10
TO LIGHT THE APPLIANCE
Check that the water valves to the central heating circuit are open.
On sealed systems check that the grey needle on the pressure
gauge is not below the required pressure.
Switch on the mains electricity. The green power on indicator
will light. Set the room thermostat, if fitted, to maximum. Turn the
central heating temperature control knob to ‘MAX’. The red central
heating demand indicator will light.
The burner will light and the red flame detection indicator will light.
Set the central heating and hot water temperature control knobs
and the room thermostat, if fitted, to the desired temperature.
TO STOP THE APPLIANCE
For Short Periods
Turn the central heating temperature control knob fully anti-
clockwise to the ‘O’ position.
For Long Periods
Turn the operating switch to the ‘O’ position. Switch off the
mains electricity. A facia mounted electronic programmer
will retain its settings for about two
weeks, after which it will return to the
factory set programme. The display will
disappear after approximately 12 hours.
A facia mounted mechanical
programmer will require resetting once
the operating switch has been set to ‘O’,
or the mains supply has been
disconnected.
ELECTRICITY SUPPLY
FAILURE
If the electricity supply fails the
appliance will not operate. Once the
supply is restored the appliance will
return to normal operation. If a
programmer is fitted, check that the
settings have been maintained.
OVERHEAT CUT-OFF
THERMOSTAT
The appliance will enter a lockout
condition in the event of overheating.
An overheat cut-off thermostat is
fitted to the appliance which will
interrupt the electricity supply to the
gas valve.
If the overheat cut-off has
operated, both the central heating and
the hot water demand indicators will
flash together.
TO LIGHT AND STOP THE
APPLIANCE
Fig. 3. Si with front casing removed.
Inner
case
cover
Facia panel
fixing screws
(2)
Facia
Fixing screws
(4)
Gas valve
Pump
Flow
switch
Air
pressure
switch
