26
Adjustment info
fig. 28
A
fig. 31
D
fig. 30
fig. 29
B
1
2
3
1
2
3
Pressure test
nipple ''D''
downstream
gas valve
Plug of max pressure
adjust screew
Maximum pressure
adjust screw ''B''
Pressure
test nipple
upstream
gas valve
2.6
ADJUSTING THE
BURNER
All the instructions below are for the exclusi-
ve use of
qualified technicians.
All the boilers leave the factory calibrated and
tested.
If it is necessary to change the calibration fol-
lowing changes in the type of gas or adapta-
tion to the supply network conditions, it is
necessary to recalibrate the gas valve.
To correctly regulate the gas valve, follow the
steps below:
1) Maximum output adjustment
-
check the value of the supply pressure (see
table NOZZLES - PRESSURES);
-
Unloose the screw
''D''
on the pressure test
nipple downstream the gas valve (fig. 30)
and connect a pressure gauge as shown
in figure 30;
-
set the
''B'
' knob (onto the panel board) to
max. position (fig.35);
-
check that the room thermostat contact
TA is closed
;
-
Switch on the power supply to the boiler
and depress the ''chimney sweeper'' switch
''H
fig. 35
'
' on the panel board: in this way
the boiler will operate at maximum output;
-
when the burner is ignited, check that the
“MAXIMUM” pressure value corresponds
to that indicated on the table “NOZZLES -
PRESSURES”: if it does not, correct it by
removing the screw plug
“A”
(fig. 28) and
by turning screw
“B”
(fig. 29) CLOCKWISE
to increase, and ANTICLOCKWISE to de-
crease
2) Minimum output adjustment
-
Depress a second time the ''chimney swee-
per'' switch
''H
fig. 35
'
' on the panel board:
in this way the boiler will operate at mini-
mum output;
-
when the burner is ignited, check the “MI-
NIMUM” pressure value corresponds to that
indicated in the table “NOZZLES - PRES-
SURES ”;
-
correct the value, if necessary, turning the
MIN GAS potentiometer
2
on the PCB
using a screwdriver (see fig.31).
3) Completion of the basic adjustement
-
check the minimum and maximum pres-
sure values of the gas valve;
-
if necessary make any fine adjustments
-
Disactivate the ''chimney sweeper'' func-
tion switching Off and On again through
the
‘’A’’
switch fig. 35.
-
Remove the plastic pipe from pressure test
nipple and close the inner screw;
-
Using a soapy solution check for gas
leaks.
PRESSURE TEST
NIPPLE
CLOCKWISE
ANTI-
CLOCKWISE
CLOCKWISE
ANTI-
CLOCKWISE
CLOCKWISE
ANTI-
CLOCKWISE
Summary of Contents for RTN 24
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