Riello GAS 8 P/M Quick start guide

2915247 (9) - 01/2015
Installation, use and maintenance instructions
Forced draught gas burners
Progressive two-stage or modulating operation
CODE MODEL TYPE
3753883 GAS 8 P/M 538 T80
3753884 GAS 8 P/M 538 T80
3754083 GAS 9 P/M 540 T80
3754084 GAS 9 P/M 540 T80
3754185 GAS 10 P/M 541 T80
3754186 GAS 10 P/M 541 T80
3754187 GAS 10 P/M 541 T80
3754188 GAS 10 P/M 541 T80
GB

2915247
1
Declaration of conformity in accordance with ISO / IEC 17050-1
Manufacturer: RIELLO S.p.A.
Address: Via Pilade Riello, 7
37045 Legnago (VR)
Product: Forced draught gas burners
Model: GAS 8 P/M
GAS 9 P/M
GAS 10 P/M
These products are in compliance with the following Technical Standards:
EN 676
EN 12100
and according to the European Directives:
MD 2006/42/EC Machine Directive
LVD 2006/95/EC Low Voltage Directive
EMC 2004/108/EC Electromagnetic Compatibility
The quality is guaranteed by a quality and management system certified in accordance with UNI EN ISO 9001.
Legnago, 03.09.2014 Executive General Manager
RIELLO S.p.A. - Burner Department Research & Development Director RIELLO S.p.A. - Burner Department
Mr. U. Ferretti Mr. R. Cattaneo

2
CONTENTS
page
1 GENERAL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
1.1 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
1.2 Available models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
1.3 Burner description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
1.4 Packaging - Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
1.5 Max. dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
1.6 Standard equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
1.7 Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
1.8 Firing rates. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
1.9 Test boiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
1.10 Gas pressure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
2 INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
2.1 Boiler plate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
2.2 Blast tube length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
2.3 Securing the burner to the boiler . . . . . . . . . . . . . . . . . . . . .8
2.4 Setting the combustion head. . . . . . . . . . . . . . . . . . . . . . . .8
2.5 Gas line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
2.6 Electrical equipment, factory-set . . . . . . . . . . . . . . . . . . .10
2.7 Electrical equipment, installer-set . . . . . . . . . . . . . . . . . . .10
3 CONTROLS AND CALIBRATIONS BEFORE FIRING . .13
3.1 Boiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
3.2 Gas line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
3.3 Combustion air . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
3.4 Electrical system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
3.5 Burner starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
4 BURNER FIRING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
5 BURNER CALIBRATION . . . . . . . . . . . . . . . . . . . . . . . . .15
5.1 Setting the combustion head. . . . . . . . . . . . . . . . . . . . . . .15
5.2 Setting the servomotor . . . . . . . . . . . . . . . . . . . . . . . . . . .16
5.3 Setting gas pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
5.4 Setting burner output. . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
5.4.1 Setting MAX output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
5.4.2 Setting MIN output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
5.4.3 Setting intermediate outputs . . . . . . . . . . . . . . . . . . . . . . .20
5.5 Setting the air pressure switch . . . . . . . . . . . . . . . . . . . . .20
5.6 Setting maximum gas pressure switch . . . . . . . . . . . . . . .20
5.7 Setting minimum gas pressure switch. . . . . . . . . . . . . . . .20
5.8 Setting combustion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
5.9 Flame present check . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
6 OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
7 FINAL CONTROLS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
8 GAS DELIVERY MEASURED AT METER. . . . . . . . . . . .23
9 THE BURNER DOES NOT OPERATE. . . . . . . . . . . . . . .23
10 MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
11 TABLE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
N.B.
Figures mentioned in the text are identified as follows:
1)(A) = part 1 of figure A, same page as text
1)(A)p.4 = part 1 of figure A, page number 4
1) = Part 1 of last figure mentioned
Warning
These instructions are an integral part of the product and should therefore
never be detached from the plant. The manufacturer will accept no re-
sponsibility whatsoever for damage to persons, animals or property
caused by non-observance of the technical requirements contained in
these instructions.

3
1 - GENERAL
1.1 TECHNICAL DATA
1) Ambient temperature and barometric pressure relating to stated output.
ELECTRICAL DATA
1.2 AVAILABLE MODELS
0 : Motor with direct starting
+ : Motor with star-delta starting
MODEL GAS 8 P/M GAS 9 P/M GAS 10 P/M
Type 538 T80 540 T80 541 T80
Output
20°C - 1000 mbar 1)
stage 2° kW
Mcal/h 1163 - 2326 1000 - 2000 1744 - 3488 1500 - 3000 2441 - 5000 2100 - 4300
stage 1° kW
Mcal/h 581 - 1163 500 - 1000 872 - 1744 750 - 1500 1140 - 2441 980 - 2100
Fuel NATURAL GAS
- Net calorific value kWh/Nm
3
Mcal/Nm
3
8,1 - 10
7 - 8,6 8,1 - 10 7 - 8,6 8,1 - 10 7 - 8,6
- absolute density kg/Nm
3
0,81 - 0,71 0,81 - 0,71 0,81 - 0,71
- max delivery Nm
3
/h 286 - 232 429-348 615-500
- pressure at maximum delivery mbar 27,8-16,5 22,6-13,4 37- 22
Operation
- On-Off (1 stop min each 24 hours) These burners are also fitted for the continuous oper-
ation, if they are equipped with the control box LANDIS type LGK 16.335 A27 (interchange-
able with the burner control box LANDIS LFL 1.335).
- Progressive two-stage (modulating by kit).
Standard applications Boilers: steam - water - diathermic oil
Ambient temperature °C 0 - 40
MODEL GAS 8 P/M GAS 9 P/M GAS 10 P/M GAS 10 P/M
Code 3753883 - 3753884 3754083 - 3754084 3754185 - 3754186 3754187 - 3754188
Electrical supply V
Hz 220V - 380V with neutral ~ +10 - 15%
60 - Three phase
220V - 380V with
neutral ~ +10 - 15%
60 - Three phase
220V - 380V with
neutral ~ +10 - 15%
60 - Three phase
220V - 380V with
neutral ~ +10 - 15%
60 - Three phase
Fan motor IE2 rpm
kW
V
A
3520
4
220/380
14.6/8.5
2920
9.2
220/380
29.1/16.8
2920
15
220/380
46.8/27
2920
15
380/660
26.6/15.4
Ignition transformer V1 - V2
I1 - I2 230 V - 1 x 8 kV 1.8 A - 30 mA
Electrical power consumption kW max 5 12 17 17
Electrical protection IP 40
MODEL GAS 9 P/M GAS 10 P/M GAS 10 P/M
Code 3754083 - 3754084 3754185 - 3754186 3754187 - 3754188
Electrical supply V
Hz 220V - 380V with neutral ~ +10 - 15%
60 - Three phase
220V - 380V with
neutral ~ +10 - 15%
60 - Three phase
220V - 380V with
neutral ~ +10 - 15%
60 - Three phase
Fan motor IE3 rpm
kW
V
A
3540
9.2
220/380
30.5/17.6
3520
15
220/380
49.2/28.4
3520
15
380/660
28.4/16.4
Ignition transformer V1 - V2
I1 - I2 230 V - 1 x 8 kV 1.8 A - 30 mA
Electrical power consumption kW max 10.7 16.9 16.9
Electrical protection IP 40
Code Model Type Motor Electrical supply three phase Blast tube
lenght mm Accessories page 5
V +10 -15 % Hz
3753883 GAS 8 P/M 538 T80 0 220-380N 60 391 A1-B1-C-D1-E-F-G
3753884 GAS 8 P/M 538 T80 0 220-380N 60 501 B2-C-D1-E-F-G
3754083 GAS 9 P/M 540 T80 0 220-380N 60 444 A2-B3-C-D2-E-F-G
3754084 GAS 9 P/M 540 T80 0 220-380N 60 574 B4-C-D2-E-F-G
3754185 GAS 10 P/M 541 T80 + 220 60 476 A3-C-D2-E-F-G
3754186 GAS 10 P/M 541 T80 + 220 60 606 C-D2-E-F-G
3754187 GAS 10 P/M 541 T80 + 380N 60 476 A3-C-D2-E-F-G
3754188 GAS 10 P/M 541 T80 + 380N 60 606 C-D2-E-F-G

4
Before installing the burner, check with your
Local Gas Authority that the maximum gas
delivery required by the plant is available and
that mains pressure and type of gas are com-
patible with the data given in Table 1.1
1.3 BURNER DESCRIPTION (A)
1Flame viewer
2Lifting rings
3Slide bars for opening the burner and in-
specting the combustion head (see note)
4Combustion head (two lengths)
5Air gate valve closed to wait for reduction of
loss of heat
6Modulating regulator (optional)
7Air pressure switch
8Gas butterfly valve drive rod
9Motor contact-maker and thermal relay
(GAS 8-9 direct starting)
10 Terminal strip
11 Fair lead (standard equipment)
(installer-set electrical equipment)
12 Control box with lock out pilot light and lock
out reset button
13 Combustion head drive rod
14 Air-gas control servomotor
15 Air setting cam
16 Gas pressure test point to sleeve
17 Max. gas pressure switch
18 Gas butterfly valve (gas input pipework)
19 MIN output gas adjustment disc
20 Sleeve
21 Fan pressure test point
22 Plug-socket on servomotor cable
1.4 PACKAGING-WEIGHT (B)
Approximate measurements.
· The burner stands on a wooden base which
can be lifted by fork-lifts.
Outer dimensions of packaging are indicated
in (B).
· The weight of the burner with the longest
combustion head including packaging is
given in (B).
1.5 MAX. DIMENSIONS (C)
Approximate measurements.
The maximum dimensions of the burner are giv-
en in (C).
Bear in mind that inspection of the combustion
head requires the burner to be opened and the
rear part withdrawn on the slide bars.
The maximum dimensions of the burner when
open are given by measurement I.
1.6 STANDARD EQUIPMENT
· 1 Gas train connection gasket
· 12 Screws
· 4 Fair leads for electrical cables
· 8 Washers
· 2 Extensions (only for long head models)
· 1 Heat shield
· 1 Motor starter (see 1.2)
· 2 Fair leads for electrical connections to
starter
· 1 Instruction booklet
NOTE
Before opening long-headed burners (501-
574-606), fit the two extensions supplied as
standard equipment with the system on slide
bars 3)(A) and support the burner on the
wheel-mounted stand supplied as an extra
unit, fig.(E)p.5, or other sui-table means.
(A)
(B)
mm A B C kg
GAS 8 P/M 1690 880 820 195
GAS 9 P/M 1870 910 920 240
GAS 10 P/M 2040 930 1101 290
mm A B C D E F G H I
GAS 8 P/M 396 755 467 260
DN 80
158 1090 391
501 1541 1644
GAS 9 P/M 447 817 496 295
DN 80
168 1200 444
574 1627 1757
GAS 10 P/M 508 917 525 336
DN 80
203 1320 476
606 1730 1860
(C)
D34
D35
D36
D37

5
1.7 ACCESSORIES (optional)
Table 1.2 shows the accessories available for
each burner
(A) SPACER
Used to reduce the length of the blast tube in
burners with short head 391 - 444 - 476.
L = spacer thickness
L1 = resulting length of blast tube
(B) KIT FOR LPG OPERATION
This kit must be fitted whenever the burner is to
be operated on LPG instead of natural gas.
L = kit for short head
L1 = kit for long head
(C) OUTPUT MODULATION REGULATOR KIT
Under modulating operation, the burner auto-
matically adapts to one of an infinite number of
firing rates between the low and high flame out-
put positions, thus ensuring stable operating
conditions in terms of temperature or pressure.
Two components should be ordered:
• output regulator to install on the burner;
• probe to install on the boiler.
(D) SOUNDPROOFING
The sound attenuating shroud significantly re-
duces the noise generated by the burner
(– 16/20 dBA). The casing is in steel and sound-
damping material and fully encloses the burner.
The casing is wheel-mounted so that it can be
easily removed for burner inspection.
(E) SUPPORT
The support should be fitted to burners with a
long head (501 - 574 - 606). It is designed to bear
the weight of the burner during head inspection.
For burners with a short head, the support is not
essential although useful.
The 1" 1/2 pipe of the support should be pre-
pared by the installer to a length appropriate to
that of the system.
The base is fitted with a wheels.
(F) KIT POTENTIOMETER
The kit consists of a potentiometer with a scale
of values of 0 - 1000 W equivalent to a travel of
0 - 100 %, with tripolar connection, to be installed
inside servomotor 14)(A)p.4. It is used to signal
the position of the servomotor for indications or
feedback to various instruments.
(G) KIT CONTINUOUS VENTILATION
The kit comprises a small three-way solenoid to
be installed between the air pressure switch
7)(A)p.4 and the fan. It allows the burner to fire
again when it has remained under continuous
ventilation following flame cut-out.
(A)
(C)
(B)
(D)
A1 COD. 3000722 L = 110 L1 = 281 mm • GAS 8 P/M
A2 COD. 3000723 L = 130 L1 = 314 mm • GAS 9 P/M
A3 COD. 3000751 L = 130 L1 = 346 mm • GAS 10 P/M
B1 COD. 3000875 L = 391 mm • GAS 8 P/M
B2 COD. 3010029 L1 = 501 mm • GAS 8 P/M
B3 COD. 3000876 L = 444 mm • GAS 9 P/M
B4 COD. 3010028 L1 = 574 mm • GAS 9 P/M
B5 COD. 3010152 L = 476 mm • GAS 10 P/M
B6 COD. 3010153 L1 = 606 mm • GAS 10 P/M
D1 COD. 3000780 • GAS 8 P/M
D2 COD. 3000781 • GAS 9-10 P/M
(E)
(F) COD. 3010021 • GAS 8-9-10 P/M
(G) COD. 3010030 • GAS 8-9-10 P/M
• GAS 8 - 9 - 10 P/M
Parametro da controllare
Zu überwachender Wert
Parameter to be checked
Paramètre à contrôler
Sonda - Fühler
Probe - Sonde Regolatore - Regler Regulator - Régulateur
Campo - Bereich
Range - Plage
Tipo - Typ
Type Codice Code Tipo - Typ Type Codice Code
Temperatura
Temperatur
Temperature
Température
- 100...+ 500 °C PT 100 3010110
RWF40 3010211
Pressione
Druck
Pressure
Pression
0...2,5 bar
0...16 bar
Sonda con uscita
Fühler mit Ausgang
Probe with output
Sonde avec sortie
4...20 mA
3010213
3010214
mm A B C D HKg
MIN MAX
D1 300 1050 1000 400 990 1660 153
D2 350 1210 1170 450 1150 1820 198
COD. 3000731 • GAS 8-9-10 P/M
D38
D39
D40

6
1.8 FIRING RATES (A)
During operation, burner output varies between:
•MINIMUM OUTPUT in stage 1 and
•MAXIMUM OUTPUT in stage 2.
MINIMUM OUTPUT (MIN) is selected from the
range of values given above the graphs.
Example:
an output of between 581 and 1163 kW (equiva-
lent to 500 and 1000 Mcal/h) may be selected for
GAS 8 P/M.
The pressure in the combustion chamber need
not be known in stage 1.
MAXIMUM OUTPUT (MAX) is selected from the
range given in the graphs to the side.
This range is referred to as the FIRING RATE
and provides maximum burner output as a func-
tion of combustion chamber pressure.
The operating point is given by plotting a vertical
from the required output and a horizontal from
the corresponding combustion chamber pres-
sure. The meeting point between the two lines
gives the operating point, which must lie within
the FIRING RATE.
Example:
for GAS 8 P/M the range is defined by:
· the 1163 - 2326 kW output axis
· the 0 +14 mbar comb. chamber pressure axis
· the maximum pressure in combustion chamber
curve.
If the burner generates an output of 2000 kW at
a combustion chamber pressure of 6 mbar, the
operating point is found on the maximum pres-
sure curve. This curve incorporates margins of
safety and therefore the entire FIRING RATE
range may be used.
Important:
the FIRING RATES have been obtained at an
ambient temperature of 20°C and a barometric
pressure of 1000 mbar.
· Burner output should be adapted to boiler out-
put in the maximum setting range, i.e. within the
FIRING RATE.
· The burner can also operate when there is a
negative pressure in the combustion chamber.
1.9 TEST BOILER (B)
Firing rates (A) were set in relation to special test
boilers in accordance with the methods defined
in DIN 4788 and UNI 8042 standards.
Figure (B) indicates the diameter and length of
the test combustion chamber.
Example: output 1500 Mcal/hour:
diameter = 80 cm; length = 2.5 m.
Whenever the burner is operated in a much
smaller commercially-available combustion
chamber, a preliminary test should be per-
formed.
1.10 GAS PRESSURE
Gas pressure in relation to maximum burner out-
put is indicated by the curves in figure (A)p.7.
They represent the drop in pressure of the com-
bustion head. Curves:
1 = Natural gas PCI10 kWh/Nm
3
-8,60 Mcal/Nm
3
absolute density - 0,71kg/Nm3
2 = Natural gas PCI8,1 kWh/Nm
3
-7,00 Mcal/Nm
3
absolute density - 0,81kg/Nm
3
Curves were calculated under the following con-
ditions:
• Pressure measured at test point 16)(A)p.4
• Combustion chamber at 0 mbar
• Combustion head set as per 2.4 and 5.1
• Burner operating at maximum output
(servomotor at end of travel: 130°)
(A)
kW
Mcal/h
Comb. chamber pressure
mbar
D41
GAS 8 P/M
GAS 9 P/M
kW
Mcal/h
Comb. chamber pressure
mbar
D351
(B)
GAS 10 P/M
kW
Mcal/h
D352
Comb. chamber pressure
mbar
Comb. chamber length
m
kW
Mcal/h
D44

7
If the approximate maximum output at which the
burner is operating must be known, record the
type of gas which was used, its pressure at test
point 16)(A)p.4 and the pressure in the combus-
tion chamber and then proceed as follows:
subtract combustion chamber pressure from gas
pressure and then refer to graph relating to the
considered burner.
Example:
· Burner GAS 9 P/M
· Natural gas PCI 10 kWh/Nm3 (curve 1)
· Gas pressure at test point 16)(4A) =13 mbar
· Pressure in combustion chamber=3 mbar
13 + 3 =10mbar
which corresponds, for GAS 9, to a maximum
output of 2900 kW.
This reading is an initial approximation.
Effective delivery should be read at the meter.
If instead the gas pressure required at test point
16)(A)p.4 must be known, set the maximum out-
put at which the burner is to operate, record the
type of gas used and chamber pressure and then
proceed as follows:
add the pressure in the combustion chamber to
the pressure indicated in graph (A); both pres-
sures correspond to maximum burner output.
Example:
· Burner GAS 9 P/M
· Max required output 2900 kW
· Natural gas PCI 10 kWh/Nm3 (curve 1)
· Gas pressure at output of 2900 kW,
GAS 9 P/M graph = 10 mbar
· Pressure in combustion chamber = 3 mbar
10 + 3 = 13 mbar
is the pressure required at test point 16)(4A).
2 - INSTALLATION
Installation should only be performed by qualified
personnel in conformity with the standards and
regulations in force where the burner is to be in-
stalled.
• Remove the packaging and make sure the
burner is in good condition. If there is any
doubt, inform the distributor.
• Collect all packaging elements and store them
in a suitable place.
2.1 BOILER PLATE (B)
Drill the combustion chamber locking plate as
shown in (B). The position of the threaded holes
can be marked using the thermal screen sup-
plied with the burner.
2.2 BLAST TUBE LENGTH
The length of the blast tube should be selected in
relation to indications provided by the boiler
manufacturer and, in any case, should be great-
er than the thickness of the boiler door complete
with refractory material.
Three different blast tube lengths are available:
• Long head (see 1.2);
• Short head (see 1.2);
• Short head plus spacer (see 1.7).
For boilers with front flue passes as shown in
15)(A)p.8 or a flame inversion chamber, the
space between the front plate quarl 17) and the
burner blast tube must be properly sealed with
an appropriate refractory material 16). After-
wards, it must still be possible to pull out the blast
tube.
(A)
mm A B C D
GAS 8 P/M 265 260 260 M16
GAS 9 P/M 300 260 260 M18
GAS 10 P/M 350 310 310 M20
D46
(B)
(C)
PROBE ELECTRODE
D101
D45

8
2.3 SECURING THE BURNER TO THE
BOILER (A)
- Detach the combustion head, as follows:
- Remove screws 5)(A) from the two slide bars
6).
- Detach head drive rod 11) by removing pin
2).
- Detach the gas throttle valve control rod 4) by
removing screw 3).
- Remove screws 7), which secure the fan
housing to the combustion head.
- Withdraw the burner by about 100-120 mm.
- Detach drive fork 8) by removing screws 12).
- At this stage, slide the burner fully out from
slide bars 6); the gas pipe 9) will also slide
out of elbow 10) together with the burner.
- Before securing the combustion head to the
boiler, make sure the probe and the electrode
are correctly positioned, as shown in (7C). If
positioning is incorrect, disassemble elbow
10)(A) from sleeve 13).
Do not rotate the probe but leave it in position as
shown in (C)p.7; positioning the probe near the
firing electrode could damage the control box
amplifier.
- Secure the blast tube to the boiler plate (B)p.7,
installing the burner heat shield 14)(A) sup-
plied as standard equipment. To do this, use
the four standard-issue screws, having first
protected the threads with an anti-grip product
(high tempera-ture grease, compounds,
graphite).
The burner-boiler installation must be hermet-
ically sealed.
- Adjust the combustion head as described in
2.4.
- Mount the fan housing on to slide bars 6)(A)
and gas pipe 9) onto elbow 10).
- Leave the burner open by about 100-120 mm.
- Refit fork 8) securing it with screws 12).
- Close the burner
- Tighten screws 7) which secure the fan hous-
ing to the combustion head
- Fit stops to slide bars 6) with screws 5)
- Re-connect push-rods 4) and 11).
2.4 SETTING THE COMBUSTION HEAD
Combustion head adjustment depends solely on
the MIN and MAX output provided by the burner.
Therefore, before setting the combustion head,
these two values must be set.
If preset MIN and MAX outputs become slightly
varied during final commissioning, the head does
not require adjustment.
Two head adjustments are required:
· a fixed gas setting, performed with the burner
open while it is being mounted on the boiler
(see 2.3).
· a variable setting of both gas and air, per-
formed with the burner closed (See 5.1 for de-
scription)
Fixed gas adjustment (B - C)
- Slacken screw 1)(B).
- Turn lock ring 2) so that indicator 3) lines up
with the required notch 4).
- Lock screw 1).
Selection of the required notch should be made
on graph (C) on the basis of the MAX output at
which the burner is expected to operate.
Example:
GAS 8 MAX heat output 1.500 Mcal/h.
NOTCH: 3.5
(B)
(A)
D48
D49
(C) NOTCHES ON LOCK RING 2)(B)
D50

9
2.5 GAS LINE
·
The gas meter must have a delivery greater
than that of the burner(s).
· The pipework between the meter and the
burner must have a cross-section appropriate
to the maximum throughput required. Be-
tween burner OFF and burner ON conditions,
there should not be a difference in pressure
greater than 0,5 mbar measured in P1.
· Pipework and couplings, which are internally
protected against corrosion, must be checked
and cleaned prior to their installation.
· Gas solenoids 8)-9)(A) must be as close as
possible to the burner to ensure gas reaches
the combustion head within the safety time
range of 2 s.
· The gas train must be held by a special sup-
port unit to avoid it being exposed to or exert-
ing mechanical stresses.
· It must also be possible to disconnect the gas
train at one point to allow the boiler hatch to be
opened.
· The gas train may be installed to the left or
right of the burner.
· When several burners are fed in parallel by the
same gas line, every gas train must be fitted
with its own pressure governor.
· All gas train components must comply with
legislation in force.
· Components carrying gas should be installed
in relation to the flow-direction arrow marked
on each component.
· No unnecessary fittings should be installed in
the gas pipework, particularly down-line from
filter 5)(A).
GAS TRAIN (A)
Supplied on request by Riello (part L)
To UNI-CIG 8042 standards.
Key (A)
1 - Gas input pipe
2 - Manual valve
3 - Vibration damping joint
4 - Pressure gauge with pushbutton cock
(as required by DIN 4788 standards)
Fitted by installer.
5 - Filter
6 - Pressure governor (vertical)
7 - Minimum gas pressure switch
8 - Safety solenoid VS (vertical)
9 - Adjustment solenoid VR (vertical)
Two adjustments:
- ignition delivery (fast-acting)
- maximum delivery (slow-acting)
10 - Standard issue burner gasket
11 - Gas adjustment butterfly valve
12 - Burner sleeve 20)(A)p.4
13 - Gasvalve8)-9)leakdetectioncontroldevice
14 - Maximum gas pressure switch
(supplied with the burner)
P1 - Mains pressure measurement
P2 - Adjustment pressure measurement
P3 - Combustion head pressure measurement
L - Optional gas train
L1 - Gas train fitted by installer
(A)
D51
BUTTERFLY VALVE 11)(A) PRESSURE LOSS in mbar,
with maximum opening and 2 types of gas:
1 = Natural gas PCI 10 kWh/Nm
3
- 8,60 Mcal/Nm
3
absolute density - 0,71 Mcal/Nm
3
1 = Natural gas PCI 8,1 kWh/Nm
3
- 7,00 Mcal/Nm
3
absolute density - 0,81 Mcal/Nm
3
GAS 8 P/M
kW 1 2
1150
1300
1450
1600
1750
1900
2050
2200
2350
0,59
0,75
0,93
1,14
1,36
1,60
1,86
2,15
2,45
0,99
1,26
1,56
1,92
2,28
2,69
3,12
3,61
4,12
GAS 9 P/M
kW 1 2
1800
2000
2200
2400
2600
2800
3000
3200
3400
3500
1,41
1,74
2,11
2,51
2,94
3,42
3,92
4,46
5,04
5,33
2,37
2,92
3,54
4,22
4,94
5,75
6,59
7,49
8,46
8,96
GAS 10 P/M
kW 1 2
2500
2800
3100
3400
3700
4000
4300
4600
4900
5000
1,08
1,35
1,65
1,99
2,35
2,75
3,18
3,64
4,13
4,30
1,81
2,27
2,77
3,34
3,95
4,62
5,34
6,11
6,94
7,22