Preliminary Operations; Connection To The Flue - Ferroli PEGASUS 2S Série Mode D'emploi

Accessing the electrical terminal block and components inside the control panel
To access the electrical components inside the control panel, follow the sequence in
fig. 2. The layout of the terminals for the various connections is given in the wiring dia-
grams in the technical data section.
fig. 2 - Accessing the terminal block
Key
A Undo the 2 self-tapping screws securing the boiler cover.
B Lift by pressing upwards and remove the cover held to the sides of the boiler by
pins.
C Undo and remove the two screws and the two plates holding the control panel.
D Turn the control panel forwards.
Any additional sensitive elements of the system's control and safety devices, tempera-
ture probe, pressure switch, thermostat bulb, etc., must be located on the delivery pipe
within 40 cm of the boiler casing rear wall (see fig. 3).
Key
A System delivery
B System return
C 40 cm max.
A
C
B
fig. 3 - Delivery and return

3.6 Connection to the flue

The flue connection pipe diameter must not be less than that of the connection on the
anti-backflow device. Starting from the anti-backflow device it must have a vertical sec-
tion at least 50 cm long. Comply with the current regulations regarding installation and
sizes of the flues and connection pipe.
The diameters of the anti-backflow device collars are given in table 1.
4. SERVICE AND MAINTENANCE
4.1 Adjustments
All adjustment and conversion operations must be carried out by Qualified Personnel.
The manufacturer declines any liability for damage or injury caused by unqualified and
unauthorised people tampering with the unit.
Burner gas pressure adjustment
The boilers PEGASUS 67 ÷ 107 2S are arranged to run on natural or liquefied gas. The
pressure setting and test are performed in the factory.
However, at first lighting, as there may be supply pressure variations, check and if nec-
essary adjust the pressure at the nozzles, respecting the values given in the technical
data table in sec. 5.3.
Pressure adjustment operations must be carried out with the boiler working, using the
pressure regulator on the 2-stage gas valves (see fig. 4)
30
EN
PEGASUS 67 ÷ 107 2S

Preliminary operations:

1. Light the boiler and turn the control thermostat knob to minimum.
2. Connect a pressure gauge to the pressure point on the gas manifold pipe of the
burner assembly (see part 14 of fig. 12).
3. Remove the protection cap of the pressure regulator 4 of fig. 4.
Minimum power (1st stage) adjustment
1. Turn the control thermostat knob slowly clockwise to the 1st click; the gas valve will
thus be supplied only on connections A and B (see fig. 4).
2. Turn the screw 6 of fig. 4, checking that the pressure matches the values given in
the technical data table in sec. 5.3.
Maximum power (2nd stage) adjustment
1. Turn the control thermostat knob to maximum; the gas valve will now be supplied
only on connections A, B and C (see fig. 4).
2. Turn the screw 5 of fig. 4, checking that the pressure matches the values given in
the technical data table in sec. 5.3.
The adjustment operations must be performed uniformly on the pressure regulators of
all the valves.
The gas pressures measured at the burner
B
gas manifold must be read at least 30 sec-
onds after making the adjustments, i.e. when
the flame has stabilised.
On completing the adjustment operations, turn the burner on and off 2 - 3 times with the
control thermostat and check that the pressure values are those just set; otherwise, it is
necessary to make another adjustment to bring the pressures to the correct values.
Gas conversion
The unit can work with Natural gas (G20-G25) or liquefied gas (G30-G31) and is factory-
set for use with one of the two gases, as clearly shown on the packing and dataplate.
Whenever the unit has to be used with a different gas, a conversion kit will be required,
proceeding as follows.
From natural to liquefied gas
1. Replace the nozzles at the main burner and pilot burner, fitting the nozzles specified
in the technical data table in sec. 5.3.
2. Remove the small cap 3 (fig. 4) from the gas valve, screw the ignition "STEP" regu-
lator 2 (contained in the conversion kit) onto the valve and refit the cap 3 on the reg-
ulator.
3. Adjust the burner gas pressures for minimum and maximum power as described in
the previous section, setting the values given in the technical data table of section
sec. 5.3.
4. Operations 2 and 3 must be performed on all the valves.
5. Apply the sticker contained in the conversion kit, near the dataplate as proof of the
conversion.
From liquefied to natural gas
Carry out the same operations described above, making sure to remove the ignition
"STEP" regulator 2 of fig. 4 of the gas valve; the cap 3 of fig. 4 must be fitted directly on
the valve.
cod. 3540S434 - Rev. 00 - 10/2020
V
5
fig. 4 - Gas conversion
8
9
6
4