PEGASUS 67 ÷ 107 2S
27
EN
3.3 Plumbing connections
Important
The heating capacity of the unit must be previously established by calculating the build-
ing's heat requirement according to the current regulations. To ensure proper operation
and long boiler life, the plumbing system must be adequately sized and complete with all
the necessary accessories.
If the delivery and return pipes follow a path where air pockets can form in certain places,
it is advisable to install vent valves at these points. Also, install a discharge device at the
lowest point in the system to allow its complete emptying.
If the boiler is installed at a lower level than the system, it is advisable to provide a flow-
stop valve to prevent the natural circulation of water in the system.
The temperature drop between the delivery manifold and the return to the boiler should
not exceed 20°C.
B
Do not use the water system pipes to earth electrical appliances.
Before installation, carefully wash all the pipes of the system to remove any residuals or
impurities that could affect proper operation of the unit.
Carry out the relevant connections as indicated in fig. 13.
It is advisable to install shutoff valves between the boiler and heating system, allowing
the boiler to be isolated from the system if necessary.
B
Make the boiler connection in such a way that its internal pipes are free of
stress.
Water system characteristics
In the presence of water harder than 25° Fr, it is advisable to use suitably treated water,
in order to avoid possible scaling in the boiler caused by hard water, or corrosion pro-
duced by aggressive water. Due to its low thermal conductivity, scaling even just a few
mm thick causes significant overheating of the boiler walls with consequent serious prob-
lems.
Water treatment is indispensable in case of very large systems (containing large
amounts of water) or with frequent introduction of replenishing water in the system. If par-
tial or total emptying of the system becomes necessary in these cases, it is advisable to
refill with treated water.
Filling boiler and system
The filling pressure with system cold system must be approx. 1 bar. If, during operation,
the system pressure falls (due to the evaporation of gases dissolved in the water) to val-
ues below the minimum described above, the user must bring it to the initial value. For
correct operation of the boiler, when hot, its pressure must be approx. 1.5-2 bar.
3.4 Gas connection
B
Before carrying out the connection, make sure the unit is arranged for using the
type of fuel available and carefully clean all the pipes of the gas system to re-
move any residues that could affect proper boiler operation.
The gas must be connected to the relevant connection (see fig. 13) in conformity with
current standards, with a rigid metal pipe or with a continuous surface flexible s/steel
tube, installing a gas cock between the system and boiler. Make sure all the gas connec-
tions are tight.
The capacity of the gas meter must be sufficient for the simultaneous use of all equip-
ment connected to it. The diameter of the gas pipe leaving the boiler does not determine
the diameter of the pipe between the unit and the meter; it must be chosen according to
its length and pressure losses, in conformity with the current regulations.
B
Do not use the gas pipes to earth electrical appliances.
3.5 Electrical connections
Connection to the power supply
The boiler must be connected to a single-phase, 230 Volt-50 Hz electric line.
B
The unit's electrical safety is guaranteed only when it is correctly connected to
an efficient earthing system in conformity with the current safety regulations.
Have the efficiency and suitability of the earthing system checked by profes-
sionally qualified personnel; the Manufacturer declines any liability for damage
caused by failure to earth the system. Also make sure the electrical system is
adequate for the maximum power absorbed by the unit, as specified on the boil-
er dataplate, in particular ensuring that the section of the system's cables is
suitable for the input.
The boiler is prewired and supplied with a connector located inside the control panel, ar-
ranged for connection to an electronic thermostatic controller (see wiring diagrams in
sec. 5.5). It is also equipped with a three-core cable for connection to the electric line.
The connections to the power supply must be made with a permanent connection and
equipped with a double-pole switch with contact gap of at least 3 mm, interposing fuses
of max. 3A between the boiler and line. It is important to respect the polarities (LINE:
brown wire / NEUTRAL: blue wire / EARTH : yellow/green wire) when making the con-
nections to the electric line.
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.
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 unauthor-
ised 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 necessary ad-
just 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)
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 as-
sembly (see part 14 of fig. 14).
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 tech-
nical data table in sec. 5.3.
A
B
C
2.6 Air/fume ducts
The diameter of the connecting pipe to the flue must not be less than that of the connec-
tion on the anti-backflow device. Starting from the anti-backflow device it must have a
vertical section at least 50 cm long. The current regulations must be respected regarding
the dimensioning and installation of the flues and connection pipe.
The boiler is a
B11BS
type equipped with a safety device (fume thermostat) that stops
the supply of gas and shuts down the unit in case of poor draught or disturbance in the
fume exhaust. Unit shutdown is indicated on the display with the code
F04
(ref. cap. 3.4).
Restarting of the unit occurs automatically 20 minutes after the end of the fault that
caused the problem. In case of repeated intervention of the device, contact qualified per-
sonnel to check the flue and chimney and eliminate the fume evacuation fault.
B
This safety device must never be tampered with or deactivated. Any operation
on the device, or its replacement, must only be carried out by qualified person-
nel using the manufacturer's original replacement parts. A functional test must
be carried out after any operation on the device.
cod. 3540S433 - Rev. 02 - 04/2018
