23
2000225231B
6 Commissioning
Diagram 6.3
Diagram 6.4
NOTE:
PILOT SHIELD
REMOVED FOR
CLARITY
SPARK GAP
2 to 4mm
10 to 20mm FLAME LENGTH
4138
VIEWING
WINDOW
SECURING
SCREW (4)
4146
4139
Loosen the main burner pressure test point screw and connect
a suitable pressure gauge, see diagram 6.2.
Make sure that any remote controls are calling for heat.
Switch on/connect the electrical supply to the boiler and heating
system, neon 1 will light.
6.4 Testing - Electrical
Turn the boiler thermostat knob fully clockwise to the maximum
setting, which is about 82
o
C (180
o
F), neon 2 will light.
The lighting sequence is automatic as follows:-
The fan operates
The spark ignition operates
The pilot solenoid opens
The pilot burner lights
The ignition spark stops
The main solenoid opens
and after a short period of time the main burner will light, look
through viewing window, see diagram 6.3.
Very cold weather may delay the operating sequence.
The main burner will stay alight until switched off, either by the
control thermostat or a remote system control.
To make sure that the flame supervision device is working
correctly the following should be done.
1. With the main burner alight, turn the gas service cock “Off”,
see diagram 6.1.
After a short period the main burner and pilot will go out.
2. The correct working of the flame supervision device is shown
by neon 4 going out within 10 seconds and the ignition starting
up.
Neons 1, 2 and 3 should stay alight.
3. If the above does not happen, refer to fault finding Section
9.1.
4. To carry on turn the gas service cock “On”, see diagram 6.1.
When the boiler switches “Off”, both the pilot and main burner
go out. The automatic lighting sequence will work again when
heat is required.
If an external control switches the boiler off, the pump will run on
for a predetermined time.
6.5 Testing - Gas
With the boiler on proceed as follows:-
The whole of the gas installation, including the meter, should be
inspected, tested for soundness and purged in accordance with
the current issue of BS6891 and in IE the current edition of I.S.
813 "Domestic Gas Installations".
Check the main burner gas pressure at least 10 minutes after
the boiler has lit, refer to Data Label.
If necessary adjust the gas pressure to obtain the required
setting turning screw clockwise, to decrease pressure, see
diagram 6.2.
Should any doubt exist about the gas rate, check it using the gas
meter test dial and stop watch, at least 10 minutes after the
burner has lit, making sure that all other gas burning appliances
and pilot lights are off.
Turn the control thermostat knob fully anticlockwise to “Off”.
Remove the pressure gauge from the test point and refit screw,
making sure a gas tight seal is made.
neon 3 will light
neon 4 will light
When the control thermostat is turned to the “Off” position, by
hand, wait at least 30 seconds before turning “On” again.
There may be an initial smell given off from the boiler when new,
this is quite normal and it will disappear after a short period of
time.
Refit the electrical controls box, see diagram 5.8.
NOTE:
The neon indicator lights on the printed circuit board are
an aid to fault finding, for details refer to Section 9.
