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 and/or injury caused by unqualified
and unauthorised persons tampering with the unit.
Turning on TEST mode
Press the heating buttons (details 3 and 4 - ) together for fig. 15 seconds to activate
the TEST mode. The boiler lights at the maximum heating power set as described in the
following section.
The heating symbol (detail 24 - fig. 1) and DHW symbol (detail 12 - fig. 1) flash on the
display.
fig. 16 - TEST mode
To deactivate the TEST mode, repeat the activation sequence.
The TEST mode is automatically disabled in any case after 15 minutes.
Heating system output adjustment
On PEGASUS D LN boilers, the firebox heating power and therefore the heat output de-
livered to the heating water can only be adjusted by means of the main burner through
the gas valve, (see fig. 18). The diagrams given in the section cap. 5.2 indicate the var-
iation in heat output delivered to the water according to the change in burner operating
pressure. Being able to adjust boiler output to the actual heating requirements means
above all reducing heat losses, and therefore obtaining fuel saving. Also, with the varia-
tion in output, also regulated by the provisions, the boilers keep their efficiency levels and
combustion characteristics practically unchanged
This operation is carried out with the boiler working and the water storage tank heated.
1.
Using a small screwdriver, remove the secondary operator protection cap 5 of the
gas valve of fig. 18.
2.
Connect a manometer to the pressure point 2 (fig. 18) located below the gas valve,
and turn the boiler thermostat knob to the maximum value.
3.
Adjust the pressure to the required value by means of the screw 6 (fig. 18), referring
to the diagrams given in section cap. 5.2.
4.
Then turn the burner on and off 2 or 3 times by means of the control thermostat and
check that the pressure value is that just set; otherwise, another adjustment must
be made to bring the pressure to the correct value.
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 on the data-
plate. Whenever a different gas to that for which the unit is arranged has to be used, a
conversion kit will be required, proceeding as follows:
1.
Replace the nozzles at the main burner and pilot burner, fitting the nozzles specified
in the technical data table on cap. 5.3, according to the type of gas used
2.
Remove the small protection cap 3 (fig. 18) from the gas valve. Using a small screw-
driver, adjust the ignition step for the required gas (G20-G25 position Dfig. 18 or
G30-G31 position E fig. 18); then refit the cap.
3.
Adjust the gas pressure at the burner, setting the values given in the technical data
table for the type of gas used.
4.
Apply the sticker contained in the conversion kit, near the dataplate as proof of the
conversion.
B
To convert the boiler from Natural Gas to LPG it is necessary to remove the
gas baffle located between the valve and the manifold pipe (ref. 1 - fig. 17).
To convert the boiler from LPG to Natural Gas it is necessary to fit the gas baf-
fle (ref. 1 - fig. 17). The correct gas baffle for each boiler model is specified in
the technical data table on sec. 5.3.
32
EN
bar
cod. 3540U012 - 02/2010 (Rev. 00)
fig. 17 - Gas baffle
Key fig. 17
1. Gas baffle
2. Seal
fig. 18 - Pressure adjustment
Key fig. 18
A
Gas valve
B
Decrease pressure
C
Increase pressure
D
Ignition step adjustment for NATURAL gas G20-G25
E
Ignition step adjustment for LIQUEFIED gas G30-G31
1
Pressure point upstream
2
Pressure point downstream
3
Protection cap
5
Protection cap
6
Pressure adjustment screw
PEGASUS D LN
1 2