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6.9.1
6.10
6.11
Detach one of the wires going to modu-
6.12
S E T T I N G C E N T R A L H E A T I N G G A S
lator 104 (Fig. 51) and make the boiler
PRESSURE THE BOILER COMES SET
operate just as was done for checking
AT MID POSITION RATING FOR USE ON
the maximum pressure.
C.H. (table 1/2/3/4)
Observe electrode. It should be about 3-4
from the burner (Fig. 52B).
CHECK THE GAS PRESSURE AT THE
BURNER LPG (G 31) - (G30)
Now check if the maximum gas pressure at
the burner is equal to 35,4 (G31) 0.5
mbar or 27.3 (G30) 0.5 mbar.
When the boiler operates in the C.H. mode
the gas pressure at the burner can be set
between the min. and max. values.
This permits capacity to be adjusted to suit
system demand. If adjustment is required
proceed as follows:
- Remove the casing. Unscrew the two
screws holding the control box and lift
off the cover.
To do this proceed as follows:
Turn off main switch 1 (Fig. 50)
- Set summer/winter switch 1 on summer
- Set control thermostat 5 at its maximum
- Switch summer/winter switch to winter
position.
- Turn control thermostat 4 to maximum
setting (Fig. 50).
- Check all external controls are on and
calling for heat ensure all D.H.W. taps
are off.
setting.
Fit a pressure gauge, using a hose, to
pressure test point 81 (Fig. 51), after
first loosening its close-off screw.
Open one or more hot water taps so
that at least 10+12 litre of water flows
per minute.
The pressure indicated on the pressure
gauge is the maximum operating gas
pressure.
-Check if the minimum pressure corre-
sponds to 9.6 mbar (G31), 6.6 mbar (G30)
for LS 80 (T) or 6.1 mbar (G31), 4.7 mbar
(G30) for LS 100 (T) as is set at the factory.
Detach one of the wires going to modula-
tor 104 (Fig. 51) and make the boiler oper-
ate just as was done for checking the max-
imum pressure.
A D J U S T I N G M I N I M U M A N D M A X I M U M
PRESSURE (Fig. 51) HONEYWELL GAS VALVE
- Remove cap covering modulator to gas
valve.
- Detach one of the cables connected to
the modulator 114.
- With the boiler operating use a 9 mm
spanner to turn the nut 111 clockwise to
increase pressure and anti-clockwise to
decrease pressure.
RECONNECTTHE DETACHED CABLE
Use a screw-driver to hold nut 111 firm a 9
mm spanner and use a 7 mm spanner
wrench to rotate the nut 110 clockwise to
increase the pressure and counter-clock-
wise to decrease it.
After adjustment turn off D.H.W.Taps.
- With boiler operating use a screwdriver
to turn potentiometer (Fig. 48) clock-
wise to increase pressure and anti-
clockwise to decrease pressure.
- To obtain the desired heat value estab-
lish pressure as per (Fig. 52).
- Replace the protective cover.
- Once this pressure is established, mark
it up on data badge with adhesive red
label/arrow burner pressure setting so
that this can be referred to and checked
during future servicing.
RATIO BETWEEN BURNER PRESSURE
AND OUTPUT NATURAL GAS (G 20)
LPG (G30 - G31)
Fig. 52B
IGNITION
ELECTRODE
BURNER
B U R N E R
SENSOR
ELECTRODE
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