INSTALLATION
mini HE
--- Installation & Servicing
27
27 TO ADJUST PRESSURES
Nomenclature of the parts on the gas valve
A Modulation operator’s electric connectors
B Minimum gas pressure adjustment
C Maximum gas pressure adjustment
D Gas valve inlet pressure test point
E Burner pressure test point
A
E
D
B
C
1 Remove the front panel of the case.
2 Open the gas valve inlet pressure test point D at the valve
input, connect a suitable pressure gauge and check the
gas pressure of the supply network.
3 Remove the gauge and close the pressure test point D.
4 Open the burner pressure test point E and connect the
gauge.
5 Remove the protection cap from the mechanical pressure
adjustment components (B and C)
6 Start the boiler at its maximum power.
Operate the boiler in DHW mode or ensure that the boiler
is not range rated if the test is carried out in CH mode.
Maximum valve setting
7 If necessary, rotate the
maximum
gas pressure
adjustment C using a spanner until you obtain the
required pressure as indicated on Table 1 at page 4
(burner pressure).
By rotating clockwise the pressure increases.
Minimum valve setting
8 Disconnect one of the two connectors A.
9 If necessary, rotate the
minimum
gas pressure adjustment
B using a pozidrive screwdriver until you obtain the
required pressure as indicated on Table 1 at page 4
(burner pressure).
By rotating clockwise the pressure increases.
10 Turn the boiler off and re---connect the wire to the
modulating operator.
11 Start the boiler and check again the maximum gas
pressure setting.
12 Turn the boiler off and disconnect the gauge and close the
gas valve outlet pressure test point E
Important: after the gas pressure checks and any
adjustment operations, all of the test points must be
sealed.
Ignition rate adjustment
1 Turn on the boiler.
2 Check that the boiler lights up uniformly and adjust the
ignition gas pressure, if necessary.
To adjust the ignition gas pressure:
3 Open the gas valve outlet pressure test point E and
connect the gauge.
4 Loosen the screws F and remove the service panel
F
Service panel
5 set dip---switch ”3” to the OFF position and adjust
potentiometer marked “ACC” with a screwdriver until
correct ignition gas pressure is obtained.
2
3 4
OFF
ON
1
ACC
+
Suggested ignition pressures:
Natural gas G20 --- 6 (2,4) mbar (in w.g.)
Propane G31 --- 13 (5,3) mbar (in w.g.)
IN
S
T
A
L
L
A
T
IO
N