Ferroli PEGASUS F2 51 User manual

INSTALLATION AND
MAINTENANCE INSTRUCTIONS
GAS-FIRED CAST-IRON BOILERS
WITH ELECTRONIC IGNITION
AND FLAME RECTIFICATION MONITORING
PEGASUS F2
Models 51 - 68 - 85 - 102
Appr. nr. A 9503 A - 0085 AQ 0765
cod. 3540724/2 - 04/98

Pegasus F2
2

3
Pegasus F2
Contents
1. General technical data
2. Dimensions and technical data
3. Installation
4. Wiring diagrams
5. Startup and shutdown
6. Gas regulation
7. Conversion
8. Maintenance and cleaning
9. Fault finding

Pegasus F2
4
1. GENERAL TECHNICAL DATA
1.01 Introduction
The Pegasus F2, with CE approval, is designed for use with natural gas (G20) or LPG (G31) for indirect
central heating and hot water.
1.02 Installation requirements
Only CORGI registered installers should fit the Pegasus boilers.
The boiler installation should comply with relevant British Standards Specifications, codes of practice,
and Current Building Regulations, together with any special Regional Requirements of the Local
Authorities, gas supplier and Insurance Companies.
2. DIMENSIONS AND TECHNICAL DATA
2.01 Dimensional data (see fig. 1 and table 2)
Fig. 1
a1 - Return 1" 1/2
a2 - flow 1" 1/2
a3 - Gas inlet 3/4"
a2
C
E
D
a1
a3
222
672
762
900
B
A
1000

5
Pegasus F2
2.02 Technical data
The standard cast-iron PEGASUS F2 boiler is set to operate on natural gas (G20).
The boiler is designed to operate with a flow temperature of 82°C and a maximum ∆t of 20°C.
Table 3
MODEL
GAS FLOW RATE
PILOT
INJECTORS
Ø mm
0,24
0,24
0,24
0,24
G.P.L. G31
No.
OF MAIN
BURNERS
3
4
5
6
GAS SUPPLY
PRESSURE
(mbars)
GAS PRESS. AT
BURNER MANIFOLD
(mbars)
Pegasus F2 51
Pegasus F2 68
Pegasus F2 85
Pegasus F2 102
MODEL
DIMENSIONS CONNECTIONS
Table 2
A
mm
550
640
720
800
B
mm
96,5
96,5
106,5
106,5
C
Ø mm
180
180
200
200
D
mm
43
46
44
42
E
mm
35
38
36
34
RETURN
a1 Ø
1 1/2"
1 1/2"
1 1/2"
1 1/2"
WEIGHT
INCLUDING
PACKAGE
Kg.
Pegasus F2 51
Pegasus F2 68
Pegasus F2 85
Pegasus F2 102
1 1/2"
1 1/2"
1 1/2"
1 1/2"
FLOW
a2 Ø
GAS
a3 Ø
3/4"
3/4"
3/4"
3/4"
MAX
OPERATING
PRESSURE
(bars)
4
4
4
4
WATER
CONTENT
(liter)
22
26
30
34
MODEL
Table 1
Pegasus F2 51
Pegasus F2 68
Pegasus F2 85
Pegasus F2 102
NUMBER OF
SECTIONS
4
5
6
7
HEAT INPUT
(GROSS)
kW
62,2
83
103,8
124,3
HEAT INPUT
(NETT)
kW
56
74,8
93,5
112
HEAT
OUTPUT
kW
51
68
85
102
260
300
350
400
15 to 23
15 to 23
15 to 23
15 to 23
Nat. G20
37
37
37
37
LPG G31
13,3
13,3
13,3
13,3
Nat. G20
36
36
36
36
LPG G31
5,9
7,9
9,9
11,8
Nat. G20
m
3
/h
4,34
5,79
7,24
8,68
LPG G31
kg/h
0,4
0,4
0,4
0,4
Nat. G20
PRINCIPALES
INJECTORS
Ø mm
2,15
2,15
2,15
2,15
G.P.L. G31
3,5
3,5
3,5
3,5
Nat. G20

Pegasus F2
6
1
89
7
2463
5
Control panel
Fig. 2b
Front view of the boiler without front casing
Fig. 2a
Key
1. Temperature-pressure gauge
2. Boiler control thermostat
3. Ignition lockout re-set botton
4. Boiler on/off switch
5. Flue gas safety thermostat
6. Limit thermostat reset botton
7. Ignition PCB
8. Electronic panel (not available UK)
1 2
4
13
14
10
12
9
816
11
15
6 3
75
2.03 Main components
9. Control panel
10. Gas valve
11. Pilot burner assembly
12. Gas burner manifold
13. Gas pressure test point
14. Automatic air vent
15. Drain cock
16. Flue gas sampling point

7
Pegasus F2
Fig. 3
2.04 Characteristic pressure drop curve
Water pressure drop in all models is shown in fig.
3. The following diagram shows the pressure drop
in the boiler as a function of the water flow rate.
12345678910
10
20
30
40
50
60
70
80
90
4 EL.
100
5 EL.
6 EL.
7 EL.
∆P mbar
Flow rate
200
2.05 Safe discharge of combustion products
The boiler comes with a FLUE GAS SAFETY THERMOSTAT, which provides a high level of safety and
control over the discharge of combustion products. This thermostat cuts off the supply of gas to the
burner in the event of a faulty flue draft.
If the FLUE GAS SAFETY THERMOSTAT has been activated, you should unscrew the protection cover
(part no. 5 in fig. 2a and 2b) and manually
“reset” the thermostat. After that, the boiler
will return to normal operation.
If the FLUE GAS SAFETY THERMOSTAT
needs to be replaced, use original
manufacturer’s parts only and make sure
the electric connections and positioning of
the bulb (see fig. 4) are correct; NEVER
UNDER ANY CIRCUMSTANCES LEAVE
THE FLUE GAS SAFETY THERMOSTAT
DISCONNECTED FROM THE ELECTRIC
CIRCUIT.
In case of frequent tripping of the thermo-
static switch, contact qualified personnel
only.
During cleaning of the draft diverter, be
careful not to damage the thermostat phial.
Flue gas safety
thermostat phial
Boiler rear view
Fig. 4

Pegasus F2
8
3. BOILER INSTALLATION
(To be performed by qualified personnel only)
3.01 General warnings
The boiler should be installed according to current regulations (see para 1.02).
We suggest fitting isolating valves between the boiler and the heating system to isolate the boiler from
the system if necessary.
The rise in temperature of the heating water (the difference between the water flow and return
temperatures) should not exceed 20°C. This is so as to prevent possible damage caused by
condensation forming in the boiler.
Combustion products should be discharged through a flue with a cross section in accordance with
current standards and not less than the boiler flue outlet connection.
Connect the gas to the boiler in accordance with current regulations. The diameter of the boiler gas
inlet gas pipe does not dictate the choice of diameter for the pipe between the boiler and the gas meter
should be calculated based upon its length and pressure drop.
3.02 Boiler water characteristics
When the water supply has a hardness of more than 25 - 30 Fr., it should be treated before entering
the heating system to prevent both scaling (caused by hard water) and corrosion (caused by aggressive
water) in the boiler. Please remember that because of their low thermal conductivity, even small scales
just a few millimetres thick cause the boiler walls to overheat considerably with serious consequences.
You must treat the water used for the heating system in the following cases:
A) Very large systems (with large volumes of water).
B) Systems where partial or complete draining - and water refilling - are frequent.

9
Pegasus F2
4. WIRING AND CONNECTION DIAGRAMS
4.01 Electrical connections
- Electrical connections should be performed according to the diagrams shown here.
- Connect the boiler to a single-phase, phase neutral, 230 V ~ 50 Hz power supply through a standard
terminal block or outlet with 2A max. fuses connected between the boiler and the power support.
Remember that the boiler should always be provided with good earthing.
IMPORTANT: If on use a 230 V room thermostat, it must be in II class.
The manufacturer disclaims any liability for damage to property or persons caused by
failure to earth the boiler correctly.
General wiring diagram for mod. 51-68
Key
24 Spark electrode
25 Pilot burner
32 Pump (not supplied)
49 Limit thermostat (manual reset)
63 Boiler control thermostat
82 Ionization probe
83 Ignition PCB
92 Flue gas thermostat
98 Boiler on/off switch
114 Water flow pressure switch (not supplied)
116 Gas pressure switch
117 Main gas valve
118 Pilot light gas valve
129 Ignition lockout re-set botton
144 Timer
160 Auxiliary contact
169 Suppression filter
Fig. 5a
Note:
• Dotted lines indicate connections to be performed during installation.
• Terminals L1, N1, 6 are reserved for connecting an electronic compensator (not available in UK)
• Main burner lighting is delayed.
4
5
N1
L1
L
131
230V
50Hz
98
N
2
3
42
6
123
144
22
20
23
32
18
17
16
4
169
21
3
78
12
11
13
10
9
114
116
3
1
4
2
129
83
2
53 713 1S 4561 B
HONEYWELL
616
118
117
19
21
17
X6
X5
X4
X3
924
92
82
1
C
160
63
2
15
14
49
14 25

Pegasus F2
10
Electrical connections diagram for mod. 51-68
Fig. 5b
Key
24 Spark electrode
25 Pilot burner
32 Pump (not supplied)
49 Limit thermostat (manual reset)
63 Boiler control thermostat
82 Ionization probe
83 Ignition PCB
92 Flue gas thermostat
98 Boiler on/off switch
114 Water pressure switch (not supplied)
116 Gas pressure switch
117 Main gas valve
118 Pilot light gas valve
129 Ignition lockout reset botton
144 Timer
160 Auxiliary contact
230V
50Hz
S 4561 B
HONEYWELL 25 82
24
X6
X5
X4
X3
39 1714256711316
129
2
4
1
3
21
C
63
3514220191817161514131211987610
N1
L1
LN LN
NL
117
118
2221 2423
49
116 160114 32
1
4
2
3
98
3
24
1
169
83
92
123
144
Note:
• Dotted lines indicate connections to be performed during installation.
• Terminals L1, N1, 6 are reserved for connecting an electronic compensator (not available in UK)
• Main burner lighting is delayed.

11
Pegasus F2
12
11
10
9
C
78
13
114
116
160
24
X6
X5
9
253713
3
1
4
2
129 163
2
92
15
14
49
2
3
42
6
31
L
1
230V
50Hz
25
20
X3
X4
14
83
61617
1
19
22
118
21
117
S 4561 B
HONEYWELL 82
32
18
17
16
4
5N1
L1
98
4
169
21
3
N
General wiring diagram for mod. 85-102
Key
24 Spark electrode
25 Pilot burner
32 Pump (not supplied)
49 Limit thermostat (manual reset)
63 Boiler control thermostat
82 Ionization probe
83 Ignition PCB
92 Flue gas thermostat
98 Boiler on/off switch
114 Water flow pressure switch (not supplied)
116 Gas pressure switch
117 Main gas valve
118 Pilot light gas valve
129 Ignition lockout re-set botton
160 Auxiliary contact
169 Suppression filter
Fig. 5c
Note: Dotted lines indicate connections to be performed during installation.
Terminals L1, N1, 6 are reserved for connecting an electronic compensator (not available in
UK)

Pegasus F2
12
Electrical connections diagram for mod. 85-102
S 4561 B
HONEYWELL
117
118
LNNL
32
49
3514220191817161514131211 2221987610
116 160
114
N1L1
LN
230V
50Hz
2
4
1
3
129
92
X4
X5
X6
X3 25 82
24
1714 1613
3
24
1
21
C
63
3925671
83
169
1
4
2
3
98
Fig. 5d
Key
24 Spark electrode
25 Pilot burner
32 Pump (not supplied)
49 Limit thermostat (manual reset)
63 Boiler control thermostat
82 Ionization probe
83 Ignition PCB
92 Flue gas thermostat
98 Boiler on/off switch
114 Water pressure switch (not supplied)
116 Gas pressure switch
117 Main gas valve
118 Pilot light gas valve
129 Ignition lockout reset botton
160 Auxiliary contact
Note: Dotted lines indicate connections to be performed during installation.
Terminals L1, N1, 6 are reserved for connecting an electronic compensator (not avbailable in
UK)

13
Pegasus F2
4.03 Exploded view of the control panel (fig. 6)
4.02 Access to the control panel internal components
For access to the terminal block and the internal components of the control panel, proceed as follows:
a - Shut off the power supply to the boiler.
b - Lift off the boiler cover (held in place by slot pins).
c - Unscrew the two screws that hold the plastic panel against the side of the boiler .
d - Rotate the panel all the way round to its locked position.
e - Carry out the work and reassemble in reverse order.
Caution: Handle the flame control electronic board (part 4 in fig. 6) and its connections with
particular care.
Key
1. Control panel
2. Wiring harness protection plate
3. Terminal block
4. Ignition PCB
5. Boiler control thermostat
6. Limit thermostat (manual reset)
7. Flue gas thermostat
8. Boiler on/off switch
9. Ignition lockout reset
10. Combined temperature and pressure gauge
Fig. 6
1
2
6
9
8
10
5
7
4
3

Pegasus F2
14
5. STARTUP AND SHUTDOWN
5.01 Checks to be carried out at first startup
It is good practice to check the following at first startup: that the cutoff valves between the boiler and
heating system are open; that all is well pressurized and vented; that there are no gas or water leaks
from the water system or boiler; that the electrical connections are correct and the earthing cable
connected to a good earthing system; that there are no inflammable liquids or materials in the
immediate vicinity of the boiler and that the flue is not blocked.
5.02 Startup procedure
- Set the boiler control thermostat knob to the desired temperature (not below 50°C).
- Open the gas cock upstream from the boiler.
- Vent gas supply pipework.
- Switch on boiler.
At this point the electronic control unit takes over and after a preset pause sends a command to the pilot
valve to open and triggers off the discharge to the spark electrodes, igniting the pilot burner.
The pilot burner flame, ionizing the detection electrode, sends a signal to the electronic control unit
which in turn sends a command to the main valve to open, igniting the main burner.
Theboilernowfunctionsautomatically,controlledbytheboilercontrolthermostatand/orbyanyother
command/control devices (room thermostat, electronic thermostat board, etc.).
Note: If after having closely followed the startup procedure the burners fail to light and the reset button
warning light on the electronic control unit is lit, it means that the board has locked out and you
should wait about 10 seconds before pressing the reset button.
After resetting, the board repeats the startup cycle.
If the burners still fail to light after the second attempt, read paragraph 9, “Fault finding”.
In the event of the electric power supply to the boiler being cut off, the burners shut down and
light up again automatically when the power returns.
5.03 Temporary shutdown
To turn the boiler off temporarily, simply switch off the power supply to the boiler. The electrical
components will be without power and the main and pilot burners will remain off.
5.04 Long-term boiler shutdown
Turn off inlet gas cock to the boiler and switch off the power supply.
Caution: If the boiler remains unused for long periods during the winter, in order to avoid frost
damages you should pour a suitable anti-freeze into the system or drain it completely.
5.05 Inspections and controls after startup
At first startup:
- Make sure the gas supply is perfectly leakproof.
- Make sure the pilot light is adequate and well adjusted.
- Test boiler ignition by starting it and turning it off using the control thermostat.
- Check that no flue products escapes from the boiler draft diverter indicating that either the flue is
blocked or the draft is insufficient.

15
Pegasus F2
- Check the efficiency of the flue while the boiler is working.
- Check that there are no leaks from the points where the boiler/flue connects to the boiler and the
flue.
- Check that gas consumption, measured by the gas meter, matches the figure indicated in the
technical data table.
- Check that the water is circulating properly between the boiler and heating units.
- Make sure that when the pilot flame is extinguished, the safety devices are activated, shutting off
the main gas burners.
6. REGULATING
As described above, the boiler is set up to operate on natural gas (G20); gas pressure has been tested
and calibrated by the manufacturer.
However, due to possible differences in pressure in the gas supply system, at first startup you should
check and if necessary adjust the pressure at the injectors to match the pressure level shown in table
3 (paragraph 2.02) of the technical data.

Pegasus F2
16
Key:
1. Inlet pressure test point
2. Outlet pressure test point
3. Gas pressure switch
4. Pilot coil electric connections
5. Main burner coil electric connections
6. Pilot burner supply
7. Main burner gas pressure adjustment screw
Fig. 7
6.02 Gas pressure adjustment with the “BM 762-014” valve in models 54 - 68
Adjust the supply pressure at the main burners by turning the stabilizer screw 7 (fig. 7).
To increase the pressure, turn the screw clockwise. To decrease the pressure, turn the screw
anticlockwise.
The pilot light requires no adjustment.
Caution: Pressure measured at pressure test points 1 and 2 (fig. 7) is displayed 30 seconds or more
after making the adjustment.
6
7
5
4
2
1
1
3
2

17
Pegasus F2
6.03 Gas pressure adjustment with the “DUNGS MBDLE 407 BO1” valve in model 85 - 102
Pe
Pa
1
3
4
5
6
8
72
9
Fig. 8
Key:
1. Inlet gas pressure test point
(Burner pressure is measured at test point on burner manifold)
2. Pilot burner supply
3. Integral gas pressure switch
4. Gas pressure switch connector (grey)
5. V1-V2 gas valve power connector (black)
6. Gas governor
7. Gas flow rate regulator (valve V2)
8. Slow startup regulator (under the cover)
9. Cover protecting the incoming gas filter.

Pegasus F2
18
Gas pressure adjustment:
- Move the protective cover by turning it on its hinges.
- Using a small screwdriver (no. 3), turn the regulating screw to
set the required pressure.
Note: The pilot light requires no adjustments.
Fig. 8a
Slow startup adjustment
- Unscrew the black plastic cap
- Using the cap as a tool turn the pin under it to the desired
setting.
- Screw the plastic cap back.
Fig. 8c
Main gas flow rate adjustment (valve V2)
- Loosen the securing screw using a screwdriver.
- Turn the knob to the required setting, then re-tighten the
securing screw.
Note: Pressure measured at pressure test points is displayed 30
seconds or more after performing the adjustment.
Fig. 8b

19
Pegasus F2
7. FUEL CONVERSION (from natural to L.P.G. Gas)
7.01 Replacing the main and pilot burner injectors
To replace the main and pilot injectors proceed as follows:
- Turn off the gas and switch off the power supply to the boiler.
- Remove the main gas burners.
- Disassemble the pilot burner (fig. 8).
- Remove the main burners from manifold.
- Replace the main and pilot injectors taking care not to spoil the main injector sealing gaskets. If they
have been damaged, replace them.
- Re-assemble with care.
- Carefully screw in fully the pressure regulating screw 7 (fig. 7) on the “BM 762-014” gas valve in
models 51-68 and the screws (fig. 8a and 8b) on the “DUNGS MBDLE 407 BO1” valve in model
85-102.
- Check that the boiler functions correctly and that there are no gas leaks.
REMEMBER: The L.P.G. injector kit may be obtained from our Commercial boiler sales department.
6.04 Pilot burner unit (fig. 9)
Key
1 Combustion chamber cover plate
2 Inspection window
3 Pilot burner
4 Ignition electrode
5. Flame rectification probe
6 Pilot injector
7. Ht lead
8. Pilot gas supply
3
3 ÷4 mm
5
8
4
Fig. 9

Pegasus F2
20
8. MAINTENANCE AND CLEANING
The following operations are to be performed by qualified personnel only.
8.01 Seasonal inspection of the boiler and flue
Before the beginning of winter you should perform a general inspection of the boiler, heating system
and flue. The inspection should verify:
That the boiler flueways, burner and flue are clean.
That the water in the system is at the correct pressure – or correct level in the case of an open system.
That all control and safety devices operate properly.
That the probeand spark electrode are free of carbon deposits.
That the pilot flame correctly aligns with the probe.
That circulation pumps are free running.
That there are no gas leaks.
That the gas flow rate and pressure are correct.
That the pressure in the expansion vessel is as indicated in table 3 (paragraph 2.02).
8.02 Cleaning the boiler and the flue
To clean the boiler and the flue, remove the burner bars from the combustion chamber.
For access to the cast-iron exchanger, proceed as follows (fig. 10): Remove the cover of the casing
secured by slot pins; pull out the insulation covering the draft diverter, remove the smoke-box
inspection cover 2 and its insulation, secured with self-threading screws 1.
Now you may clean all the smoke passages in the boiler using a pipe brush 3. Remember you should
check and if necessary clean the flue and its connection to the boiler. Be careful not to damage the Flue
gas safety thermostat phial or capillary.
Important - Do not clean the burners with chemicals or a steel
brush, as these might change the air-gas mixture outlet holes.
When cleaning is complete, re-assemble carefully and in the
correct position. Then check the seal along the gas and smoke
circuits, functioning of the control and safety devices and gas
pressure and rate of flow.
Key
1Securing screws
2Inspection cover with insulation
3Flue cleaning brush
4Flue gas sampling point
Fig. 10
1
2
4
3