Riello G20 Quick start guide

20013653(4) - 07/2017
Installation, use and maintenance instructions
安装 , 使用以及维护说明书
Light oil burner
轻油燃烧器
CODE - 编码 MODEL - 型号 TYPE - 类型
20013616 G20 474T1
20137313 G20 474T1
GB
CN
One stage operation
一段火运行

20013653
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INFORMATION ABOUT THE INSTRUCTION MANUAL
INTRODUCTION
The instruction manual supplied with the burner:
- is an integral and essential part of the product and must not be
separated from it; it must therefore be kept carefully for any
necessary consultation and must accompany the burner even if it is
transferred to another owner or user, or to another system. If the
manual is lost or damaged, another copy must be requested from the
Technical Assistance Service of the area;
- is designed for use by qualified personnel;
- offers important indications and instructions relating to the installation
safety, start-up, use and maintenance of the burner.
DELIVERY OF THE SYSTEM AND THE INSTRUCTION
MANUAL
When the system is delivered, it is important that:
- The instruction manual is supplied to the user by the system
manufacturer, with the recommendation to keep it in the room where
the heat generator is to be installed.
- The instruction manual shows:
- the serial number of the burner;
- the address and telephone number of the nearest Assistance
Centre;
- The system supplier carefully informs the user about:
- the use of the system,
- any further tests that may be necessary before the system is
started up,
- maintenance and the need to have the system checked at least
once a year by the manufacturer or another specialised
technician.
To ensure a periodic check, recommends the drawing up
of a Maintenance Contract.
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1 20013653
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TECHNICAL DATA
TYPE 474T1
Thermal power – output 95 – 213 kW – 8 – 18 kg/h
Fuel Light oil, viscosity 4 –6 mm2/s at 20°C
Electrical supply Single phase, 230 V ± 10% ~ 50Hz
Motor Run current 1.4 A – 2750 rpm – 288 rad/s
Capacitor 5 F
Ignition transformer Secondary 8 kV – 16 mA
Pump Pressure 7 – 15 bar
Absorbed electrical power 0.320 kW
Burner with CE marking in conformity with EEC Directives: Electromagnetic Compatibility 2014/30/UE,
Low Voltage 2014/35/UE, Machines 2006/42/EC.
The burner meets protection level of IP 40, EN 60529.
1 – Return line
2 – Suction line
3 – Gauge connection
4 – Pump pressure regulator
5 – Vacuum gauge connection
6 – Screws fixing air-damper
7 – Air-damper
8 – Lock-out lamp and reset button
9 – Flange with insulating gasket
10 – Combustion head adjustment screw
BURNER EQUIPMENT
Quantity Description
2
1
4
1
1
1
Flexible pipes with nipples
Flange with insulating gasket
Screws and nuts for flange
Hinge
Screw with two nuts for flange
Grommet
5
D7179
Fig. 1
1
2
3
4
86
7
9
10
6

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WORKING FIELD
1.8
0
1.2
Pressure in the combustion
chamber – mbar
8 10 12 14 Fuel output - kg/h
90 110 230 Thermal power - kW
D5282 130 150 170 190 210
0.6
16 18 20
OVERALL DIMENSIONS
Flange Burner
350 118 295
160
=
41
45°
ø 125
298
11
230
D5283
=
213
99 99
190
45°
BOILER FIXING
It is necessary that the insulating gasket
(9, fig. 1) is placed between the boiler door
and the burner flange.
This insulating gasket has four holes,
which, if necessary, can be modified as
shown on the drawing on the right.
D5242
Fig. 2
Verify that the installed
burner is lightly leaned
towards the button. 
(See figure 2).
The burner is designed to
allow entry of the flexible
oil-lines on either side of
the burner.
D5572
BURNER FIXING AND
HINGE ASSEMBLY
S7385

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HYDRAULIC SYSTEMS
Warning: before starting the burner make sure that the return pipe-line is not clogged: any obstruction
would cause the pump seals to break.
The pump vacuum should not exceed a
maximum of 0.4 bar (30 cm Hg).
Beyond this limit gas is released from
the oil.
Oil lines must be completely airtight.
The return line should terminate in
the oil tank at the same level as the
suction line; in this case a non-return
valve is not required.
When the return line arrives over the
fuel level, a non-return valve must be
used. This solution however is less safe
than previous one, due to the possibility
of leakage of the valve.
PRIMING THE PUMP
Start the burner and wait for the priming.
Should lock-out occur prior to the arrival
of the fuel, await at least 20 seconds
before repeating the operation.
A filter must be installed on the suction fuel line.
H
meters
L meters
I. D.
8 mm
I.D.
10 mm
0.5
1
1.5
2
10
20
40
60
20
40
80
100
WARNING
The pump is supplied for use with a two pipe system. 
For use on a one pipe system, it is necessary to remove the by-pass
screw (A), (see figure).
A
H
meters
L meters
I. D.
8 mm
I.D.
10 mm
0
0.5
1
1.5
2
3
3.5
35
30
25
20
15
8
6
100
100
100
90
70
30
20
H max. 4 m
H
H
max. 4 m
min. 0.1 m
D5219
D5220
D5199
H=Difference of level.
L=Max. length of the 
suction line.
I.D.=Internal diameter of the
oil pipes.
PRIMING THE PUMP
Loosen the plug of the vacuum gauge (5, fig. 1,
page 1) and wait until the fuel flows out.

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ELECTRICAL WIRING
S7029
Brown
White (50V)
Blue
Motor
Capacitor
Regulating thermostat
Neutral
Switch with fuse
6A max.
NL
M
~
Black
NOTES
–Wires of 1 mm
2 section.
– The electrical wiring carried out by the installer
must be in compliance with the rules in force in
the Country.
– To remove the control-box from the burner,
loosen screw (A) (see figure) and pull towards
the arrow.
– The flame sensor is fitted directly into the control-
box (underneath the ignition-transformer) on a
plug-in support.
TESTING
Check the shut-down of the burner by opening the
thermostats.
WARNING
Do not exchange the neutral with the phase.
230V ~50Hz
NL
Limit thermostat
with manual resetting
Remote lock-out lamp
(230V - 0.5A max.), if required
123456789
Blue
Brown
Terminal block of
control-box 530SE*
Valve
T
T
RUN OF THE ELECTRICAL CABLE
1 - Grommet N - Neutral
2 - Cable-clamp L - Phase
3 - Terminal block - Burner-earth
ATTENTION
Do not connect burner’s grounding, to
failure indicator terminal . This may
result the destroy of the control box.
D5228
Black
CARRIED-OUT BY THE INSTALLER
CARRIED-OUT IN THE FACTORY

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COMBUSTION ADJUSTMENT
In conformity with EN267 the application of the burner on the boiler, adjustment and testing must be
carried out observing the instruction manual of the boiler, including verification of the CO and CO2
concentration in the flue gases, their temperatures and the average temperature of the water in the
boiler.
To suit the required appliance output, fit the nozzle then adjust the pump pressure, the setting of the
combustion head and the air damper opening in accordance with the following schedule.
The values shown in the table are measured on a CEN boiler (as per EN 267).
They refer to 12.5% CO2 at sea level and with light oil and room temperature of 20 °C.
Nozzle
1
Pump pressure
2
Burner output Comb. head
adjustment
3
Air damper
adjustment
4
GPH Angle bar kg/h ± 4% Set-point Set-point
2,00 60° 12 8,0 1 3
2,25 60° 12 9,0 1,5 3,2
2,50 60° 12 10,0 23,5
3,00 60° 12 12,0 2,5 4,3
3,50 60° 12 14,0 3,5 5,5
4,00 60° / 45° 12 16,1 56,5
4,50 60° / 45° 12 18,0 6 7
1
NOZZLES RECOMMENDED: Monarch type R - PLP ; Delavan type B - W
Steinen type S - SS ; Danfoss type S - B
Angle:60° :in most cases. Particularly suited to avoid flame-
detachment during ignition.
45° : for narrow and long combustion-chambers.
2
PRESSURE: 12 bar : the pump leaves the factory set at this value
14 bar : improves flame retention; it is therefore suitable for ignitions at
low temperatures.
3
COMBUSTION HEAD SETTING:This is done when fitting the nozzle, with the blast tube
removed. It depends on the output of the burner and is
carried out by rotating the regulating rod, till the terminal
plane of the blast tube is level with the set-point, as indicated
in the schedule.
D5284
In the sketch on the left, the combustion
head is set for an output of 3.50 GPH at
12 bar, while the shutter is level with set-
point 3.5, as required by the above
schedule.
Blast tube
Regulating rod
Shutter
Terminal plane of the blast tube
2
135

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Combustion head settings indicated in the schedule are valid for most cases.
The setting of the fan output according to the installation should normally be done only through the air
damper. Should one subsequently want to retouch also the setting of the combustion head, with the
burner running, operate on the rod (1) with a 6 mm spanner (2) as follows:
TURN TO THE RIGHT: (sign +)
In order to increase the volume of air entering the combustion chamber and thus diminishing its
pressure. There is a reduction of CO2 and the adhesion of the flame to the air diffuser disc improves. 
(Setting advisable for ignitions at low temperatures).
TURN TO THE LEFT: (sign –)
In order to reduce the volume of air entering the combustion chamber and thus increasing its pressure.
The CO2 improves and the adhesion of the flame to the diffuser tends to reduce. 
(This setting is not advisable for ignitions at low temperatures).
In any case do not bring the combustion head setting more than one point away from that indicated in
the schedule. One set-point corresponds to 3 turns of the rod; a hole (3) at its end facilitates counting
the number of turns.
1
2 3
6
D5285
1
2
D5231
4
AIR DAMPER ADJUSTMENT
The regulation of the air-rate is made by adjusting the air damper (1), after loosing the screws (2). 
When the optimal regulation is reached, screw tight the screws (2).
The settings indicated in the schedule are purely indicative.
Each installation however, has its own unpredictable working conditions: actual nozzle output;
positive or negative pressure in the combustion-chamber, the need of excess air, etc. All these
conditions may require a different air-damper setting.

PANEL
D7178
7 20013653
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It is important to take account of the fact that the air
output of the fan differs according to whether the
burner has its metal cover fitted or not.
Therefore we recommended to proceed as follows:
– adjust the air damper as indicated in the schedule (4);
– mount the cover, simply by means of the upper
screw;
– check smoke number;
– should it become necessary to modify the air output,
remove the cover by loosening the screw, adjust the
air damper, remount the cover and finally recheck the
smoke number.
NOTE: When the burner works at a firing rate
higher than 17 kg/h remove the panel fitted
inside the metal cover. (See figure).
ELECTRODE SETTING
Attention:
Before assembling or removing the nozzle, loosen
the screw (A) and move the electrodes ahead.
4± 0.3 mm
D5288 A6.5 ± 0.5 mm
MOVE THE ELECTRODE
HOLDER BACKWARDS TO
THE END
BURNER START-UP CYCLE
Normal Lock-out, due to light-failure
Thermostat
Motor
Ignition transformer
Valve
Flame
Lock-out lamp
~ 12s D5229 ~ 12s ~ 5s

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ADJUSTMENTS, TO AVOID FLAME - DETACHMENT, AT BURNER - IGNITION
1) CORRECT POSITIONING OF THE ELECTRODES
4± 0.3 mm
D5288 A6.5 ± 0.5 mm
MOVE THE ELECTRODE
HOLDER BACKWARDS TO
THE END
2) NOZZLE: ATOMIZING ANGLE
Choose 60° nozzle.
3) PUMP - SETTING
The pump is factory set, at a pressure of 12 bar.
When the temperature of the gas-oil decreases below + 5 °C, increase the pressure to 14 bar.
4) COMBUSTION-HEAD SETTING
Regulate the combustion-head one set-point further ahead than indicated in the instructions.
Example: the instructions require to set the combustion-head on set-point 3.5.
Instead, the setting is made on set-point 4.5.
5) FAN - AIR DAMPER ADJUSTMENT
Adjust the damper, reducing the excess air until the Bacharach number is not near 1.
(i.e. a combustion with the lowest possible excess-air).