Riello RX25 S/PV H Quick start guide

20030020 (4) - 04/2013
Installation, use and maintenance instructions
Instrucciones de instalación, montaje y funcionamiento
Premixed gas burners
Quemadores de gas pre-mezclado
Progressive two-stage or modulating operation
Funcionamiento a dos llamas progresivo o modulante
CODE - CÓDIGO MODEL - MODELO TYPE - TIPO
20030050 RX25 S/PV H 901T3
20026958 RX70 S/PV H 901T2
GB
E

1 20030020
GB
Contents
1 Declaration.................................................................................................................................................................................. 3
2 Information and general warnings............................................................................................................................................ 4
2.1 Information about the instruction manual........................................................................................................................ 4
2.1.1 Introduction..................................................................................................................................................................... 4
2.1.2 General dangers............................................................................................................................................................. 4
2.1.3 Danger: live components................................................................................................................................................ 4
2.2 Guarantee and responsibility .......................................................................................................................................... 5
3 Safety and prevention................................................................................................................................................................ 6
3.1 Introduction..................................................................................................................................................................... 6
3.2 Personnel training........................................................................................................................................................... 6
4 Technical description of the burner......................................................................................................................................... 7
4.1 Models available............................................................................................................................................................. 7
4.2 Technical data ................................................................................................................................................................ 7
4.3 Destination country - Gas category ................................................................................................................................ 7
4.4 Accessories .................................................................................................................................................................... 7
4.4.1 Software diagnostics kit.................................................................................................................................................. 7
4.5 Maximum dimensions..................................................................................................................................................... 8
4.6 Description of the burner ................................................................................................................................................ 8
4.7 Burner equipment ........................................................................................................................................................... 8
5 Installation .................................................................................................................................................................................. 9
5.1 Notes on safety for the installation.................................................................................................................................. 9
5.2 Handling.......................................................................................................................................................................... 9
5.3 Preliminary checks.......................................................................................................................................................... 9
5.4 Generator plate............................................................................................................................................................... 9
5.5 Securing the burner to the generator............................................................................................................................ 10
5.6 Positioning the probe - electrode.................................................................................................................................. 10
5.7 Positioning the diaphragm (LPG operation).................................................................................................................. 10
5.8 Fuel supply ................................................................................................................................................................... 11
5.8.1 Gas train assembly....................................................................................................................................................... 11
5.8.2 Gas valve...................................................................................................................................................................... 11
5.8.3 Testing.......................................................................................................................................................................... 12
5.8.4 Ionisation current .......................................................................................................................................................... 12
6 Operation .................................................................................................................................................................................. 13
6.1 Notes on safety for the first start-up.............................................................................................................................. 13
6.2 Adjustments prior to ignition ......................................................................................................................................... 13
6.3 Burner start-up.............................................................................................................................................................. 13
6.4 Fan adjustment............................................................................................................................................................. 13
6.5 Gas valve adjustment ................................................................................................................................................... 14
6.6 Burner adjustment ........................................................................................................................................................ 14
6.6.1 Second stage output..................................................................................................................................................... 14
6.6.2 First stage output.......................................................................................................................................................... 14
6.6.3 Start-up output.............................................................................................................................................................. 15
6.7 Combustion head.......................................................................................................................................................... 15
6.8 Emissions ..................................................................................................................................................................... 15
6.9 Operating programme................................................................................................................................................... 16
6.9.1 Normal operation .......................................................................................................................................................... 16
6.9.2 Lockout due to ignition failure....................................................................................................................................... 17
6.9.3 Lockout due to a flame or flame simulation detected during pre-purging ..................................................................... 17
6.10 Recycle function if flame goes out during operation..................................................................................................... 17
6.11 Restart function following firing failure.......................................................................................................................... 18
6.12 Control of the motor rpm............................................................................................................................................... 18
6.13 Control box reset (using built-in button)........................................................................................................................ 18

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Contents
6.14 Control box reset (using remote connection) ................................................................................................................18
7 Maintenance ..............................................................................................................................................................................19
7.1 Notes on safety for the maintenance.............................................................................................................................19
7.2 Maintenance programme ..............................................................................................................................................19
7.2.1 Maintenance frequency .................................................................................................................................................19
7.2.2 Checking and cleaning ..................................................................................................................................................19
8 Faults / Solutions......................................................................................................................................................................20
8.1 Start-up problems..........................................................................................................................................................20
8.2 Operating faults .............................................................................................................................................................21
9 Warnings and safety.................................................................................................................................................................22
9.1 Basic safety rules ..........................................................................................................................................................22
10 Electrical wiring ........................................................................................................................................................................23
10.1 Electrical panel layout ...................................................................................................................................................23

3 20030020
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Declaration
1Declaration
Declaration of conformity in accordance with ISO / IEC 17050-1
Manufacturer: RIELLO S.p.A.
Address: Via Pilade Riello, 7
37045 Legnago (VR)
Product: Pre-mixed gas burner
Model: RX70 S/PV H
These products are in compliance with the following Technical Standards:
EN 12100
EN 676
and according to the European Directives:
GAD 2009/142/EC Gas Devices Directive
MD 2006/42/EC Machine Directive
LVD 2006/95/EC Low Voltage Directive
EMC 2004/108/EC Electromagnetic Compatibility
Such products are marked as follows:
The quality is guaranteed by a quality and management system certified in accordance with UNI EN ISO 9001.
Declaration of Conformity A.R. 8/1/2004 & 17/7/2009 – Belgium
Manufacturer:
RIELLO S.p.A.
37045 Legnago (VR) Italy
Tel. ++39.0442630111
www.rielloburners.com
Distributed by:
RIELLO NV
Ninovesteenweg 198
9320 Erembodegem
Tel. [phone]
Fax. [phone]
e-mail. [email protected]
URL. www.riello.be
This document certifies that the series of devices specified below is in compliance with the model described in the EC Declaration of Conformity and
has been manufactured and distributed in compliance with the requirements defined in the Legislative Decree of January 8th 2004 and July 17th
2009.
Type of product: Pre-mixed gas burners
Model: RX70 S/PV H
Regulation applied: EN 676 e A.R. of January 8th 2004 - July 17th 2009
Values measured: RX70 S/PV H CO max: 20 mg/kWh
NOx max: 58.2 mg/kWh
Controlling organisation:
TÜV Industrie Service GmbH
TÜV SÜD Gruppe
Ridlerstrase, 65
80339 München DEUTSCHLAND
Manufacturer's Declaration
RIELLO S.p.A. declares that the following products comply with the NOx emission limits specified by German standard “1. BImSchV release
26.01.2010”.
Product Type Model Power
Pre-mixed gas burners 901T3 RX25 S/PV H 12 ÷ 25 kW
901T2 RX70 S/PV H 22 ÷ 33 kW
Legnago, 08.04.2013 Executive Director
RIELLO S.p.A. - Burner Department
Research & Development Director
RIELLO S.p.A. - Burner Department
Mr. I. Zinna Mr. R. Cattaneo
RX70 S/PV H CE-0085BR0101

20030020 4
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Information and general warnings
2.1 Information about the instruction manual
2.1.1 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.
Symbols used in the manual
In some parts of the manual you will see triangular DANGER
signs. Pay great attention to these, as they indicate a situation of
potential danger.
2.1.2 General dangers
The dangers can be of 3 levels, as indicated below.
2.1.3 Danger: live components
Other symbols
Abbreviations used
Ch. Chapter
Fig. Figure
Pag. Page
Sec. Section
Tab. Table
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 Assist-
ance 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 special-
ised technician.
To ensure a periodic check, the manufacturer recom-
mends the drawing up of a Maintenance Contract.
2 Information and general warnings
DANGER
Maximum danger level!
This symbol indicates operations which, if not car-
ried out correctly, cause serious injury, death or
long-term health risks.
WARNING
This symbol indicates operations which, if not car-
ried out correctly, may cause serious injury, death
or long-term health risks.
CAUTION
This symbol indicates operations which, if not car-
ried out correctly, may cause damage to the ma-
chine and/or injury to people.
DANGER
This symbol indicates operations which, if not car-
ried out correctly, lead to electric shocks with le-
thal consequences.
ENVIRONMENTAL PROTECTION
This symbol gives indications for the use of the
machine with respect for the environment.
This symbol indicates a list.
.........................................................................................
.........................................................................................
.........................................................................................
.........................................................................................

5 20030020
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Information and general warnings
2.2 Guarantee and responsibility
The manufacturer guarantees its new products from the installa-
tion date, in accordance with the regulations in force and/or the
sales contract. At the moment of the first start-up, check that the
burner is integral and complete.
In particular, the rights to the guarantee and the responsibility will
no longer be valid, in the event of damage to things or injury to
people, if such damage/injury was due to any of the following
causes:
incorrect installation, start-up, use and maintenance of the
burner;
improper, incorrect or unreasonable use of the burner;
intervention of unqualified personnel;
carrying out of non authorised modifications on the equip-
ment;
use of the burner with safety devices that are faulty, incor-
rectly applied and/or not working;
installation of untested supplementary components on the
burner;
powering of the burner with unsuitable fuels;
faults in the fuel power supply system;
use of the burner even following an error and/or an irregular-
ity;
repairs and/or overhauls incorrectly carried out;
modification of the combustion chamber with inserts that
prevent the regular development of the flame, as structurally
established;
insufficient and inappropriate surveillance and care of those
burner components most subject to wear and tear;
use of non-original components, including spare parts, kits,
accessories and optionals;
force majeure.
The manufacturer furthermore declines any and every re-
sponsibility for the failure to observe the contents of this
manual.
WARNING
Failure to observe the information given in this
manual, operating negligence, incorrect installa-
tion and the carrying out of non authorised modifi-
cations will result in the annulment by the
manufacturer of the guarantee that it supplies with
the burner.

20030020 6
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Safety and prevention
3.1 Introduction
The burners have been designed and built in compliance with
current regulations and directives, applying the known technical
rules of safety and envisaging all the potential danger situations.
It is necessary, however, to bear in mind that the imprudent and
clumsy use of the equipment may lead to situations of death risk
for the user or third parties, as well as the damaging of the burner
or other items. Inattention, thoughtlessness and excessive confi-
dence often cause accidents; the same applies to tiredness and
sleepiness.
It is a good idea to remember the following:
The burner must only be used as expressly described. Any
other use should be considered improper and therefore dan-
gerous.
In particular:
it can be applied to boilers operating with water, steam, diather-
mic oil, and to other users expressly named by the manufacturer;
the type and pressure of the fuel, the voltage and frequency of the
electrical power supply, the minimum and maximum deliveries for
which the burner has been regulated, the pressurisation of the
combustion chamber, the dimensions of the combustion cham-
ber and the room temperature must all be within the values indi-
cated in the instruction manual.
Modification of the burner to alter its performance and desti-
nations is not allowed.
The burner must be used in exemplary technical safety con-
ditions. Any disturbances that could compromise safety must
be quickly eliminated.
Opening or tampering with the burner components is not
allowed, apart from the parts requiring maintenance.
Only those parts envisaged by the manufacturer can be
replaced.
3.2 Personnel training
The user is the person, body or company that has acquired the
machine and intends to use it for the specific purpose. He is re-
sponsible for the machine and for the training of the people work-
ing around it.
The user:
undertakes to entrust the machine exclusively to suitably
trained and qualified personnel;
must take all the measures necessary to prevent unauthor-
ised people gaining access to the machine;
undertakes to inform his personnel in a suitable way about
the application and observance of the safety instructions.
With that aim, he undertakes to ensure that everyone knows
the use and safety instructions for his own duties;
must inform the manufacturer if faults or malfunctioning of
the accident prevention systems are noticed, along with any
presumed danger situation.
Personnel must always use the personal protective equip-
ment envisaged by legislation and follow the indications
given in this manual.
Personnel must follow all the danger and caution indications
shown on the machine.
Personnel must not carry out, on their own initiative, opera-
tions or interventions that are not within their province.
Personnel are obliged to inform their superiors of every
problem or dangerous situation that may arise.
The assembly of parts of other makes, or any modifications,
can alter the characteristics of the machine and hence com-
promise operating safety. The manufacturer therefore
declines any and all responsibility for any damage that may
be caused by the use of non-original parts.
3 Safety and prevention

7 20030020
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Technical description of the burner
4.1 Models available
4.2 Technical data
4.3 Destination country - Gas category
NOTES:
The requested protection level must be reached on the
application.
Temperature and operation of the burner from 0° C to 60° C.
4.4 Accessories
4.4.1 Software diagnostics kit
There is a special kit available that reports the life of the burner
by means of an optical link with the PC, indicating hours of oper-
ation, number and type of lockouts, serial number of control box
and motor rpm.
To view diagnostics, proceed as follows:
Connect the kit supplied separately to the relevant control
box socket.
Reading of the information begins once the software pro-
gram included in the kit starts running.
4 Technical description of the burner
Designation Voltage Code
RX25 S/PV H 230V/50-60Hz 20030050
RX70 S/PV H 230V/50-60Hz 20026958
Model RX25 S/PV H RX70 S/PV H
Thermal power kW
Kcal/h
12 - 25 kW
10,320 - 21,500 Kcal/h
22 - 33 kW
18,900 - 34,400 Kcal/h
Natural gas - (Family 2) G20 Ncv: 9.45 kWh/Sm3 = 8,100 kcal/Sm3- Pressure 10 - 30 mbar
G25 Ncv: 8.125 kWh/Sm3 = 7,000 kcal/Sm3- Pressure 10 - 30 mbar
LPG - (Family 3) G31 Ncv: 24.44 kWh/Sm3 = 21,000 kcal/Sm3- Pressure 10 - 30 mbar
Electrical supply Single-phase, 230V ~±10% , 50 Hz
Motor Max 6,840 rpm - 50/60 Hz
Ignition transformer Primary 220V/240 - 50/60Hz– Secondary 15 kV - 25 mA
(1) Reference conditions:
Air temperature 20°C - Gas temperature 15°C - Barometric pressure 1013 mbar - Altitude 0 m a.s.l.
Country
AT - CH - CZ - DK - EE - ES
FI - GB - GR - IE - IT - LT - LV
NO - PT - SE
BE - DE - DK - ES - FI - FR
GB - GR - IE - IT - LU - NO
PT - SE
AT - BE - CH - CZ - DE - ES
FR - GB - GR - IE - IT - PT
Gas category I2H I2R I3P
Gas pressure 20mbar 20/25mbar 29mbar
Country DE BE LU - PL FR
Gas category I2ELL I2E(R)B I2E I2Er
Gas pressure 20mbar 20/25mbar 20mbar 20/25mbar

20030020 8
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Technical description of the burner
4.5 Maximum dimensions
The maximum dimensions of the burner and flange are shown in
Fig. 1.
4.6 Description of the burner
1 Reset button with lockout signal
2 Control box
3 Gas valve
4 Air/gas mixer in intake circuit
5 Flange
6 Motor/Fan
7 Combustion head with metal mesh
8 Ignition transformer
9 Adjustment No. of fan turns
10 7 pole socket
11 Terminal board
12 Manifold
13 Ignition electrode
14 Flame detection probe
4.7 Burner equipment
Gas valve fitting + screws . . . . . . . . . . . . . . . . . . . . . . . . . No. 1
Insulating gasket . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . No. 1
7 pin plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . No. 1
Screws and nuts for fixing the flange to the boiler . . . . . . . No. 4
Suction line. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . No. 1
Diaphragm for LPG operation . . . . . . . . . . . . . . . . . . . . . . No. 1
Instruction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . No. 1
Spare parts list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . No. 1
Fig. 1
54
212
125
537
316
305
320
D10754
Fig. 2
RESET
ALARM
1
2
5
78911
3
4
6
10
12
D10755

9 20030020
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Installation
5.1 Notes on safety for the installation
After carefully cleaning all around the area where the burner will
be installed, and arranging the correct lighting of the environ-
ment, proceed with the installation operations.
5.2 Handling
The packaging of the burner includes a wooden platform, so it is
possible to move the burner (still packaged) with a transpallet
truck or fork lift truck.
5.3 Preliminary checks
Checking the consignment
Checking the characteristics of the burner
Check the identification label of the burner, showing:
the model A)(Fig. 3) and type of burner B);
the year of manufacture, in cryptographic form C);
the serial number D);
the electrical supply data E);
the electrical power consumption F);
the types of fuel used and the relative supply pressures G);
the data of the burner's minimum and maximum output pos-
sibilities H).
5.4 Generator plate
Pierce the closing plate of the combustion chamber, as in Fig. 4.
The position of the threaded holes may be marked using the gas-
ket joint supplied with the burner.
5 Installation
DANGER
All the installation, maintenance and disassembly
operations must be carried out with the electricity
supply disconnected.
WARNING
The installation of the burner must be carried out
by qualified personnel, as indicated in this manual
and in compliance with the standards and regula-
tions of the laws in force.
WARNING
The handling operations for the burner can be
highly dangerous if not carried out with the great-
est attention: keep any unauthorised people at a
distance; check the integrity and suitableness of
the available means of handling.
Check also that the area in which you are working
is empty and that there is an adequate escape
area (i.e. a free, safe area to which you can quick-
ly move if the burner should fall).
When handling, keep the load at not more than
20-25 cm from the ground.
CAUTION
After positioning the burner near the installation
point, correctly dispose of all residual packaging,
separating the various types of material.
Before proceeding with the installation operations,
carefully clean all around the area where the burn-
er will be installed.
CAUTION
After removing all the packaging, check the integ-
rity of the contents. In the event of doubt, do not
use the burner; contact the supplier.
The packaging elements (wooden cage or card-
board box, nails, clips, plastic bags, etc.) must not
be abandoned as they are potential sources of
danger and pollution; they should be collected
and disposed of in the appropriate places.
WARNING
The burner output must be within the boiler's firing
rate;
WARNING
A burner label that has been tampered with, re-
moved or is missing, along with anything else that
prevents the definite identification of the burner
and makes any installation or maintenance work
difficult.
A
R.B.L.
BC
DEF
GAS
GAZ G
G
X
....
I
2R
H
H
RIELLOS.p.A. I-37045 Legnago(VR)
I
3P
Fig. 3
D10487
Fig. 4
150 130
45
98
11
D10792

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Installation
5.5 Securing the burner to the generator
For the installation proceed as follows:
Fix the burner 1)(Fig. 5) to the generatore door 2) using the
4 screws and (if necessary) the 4 nuts supplied to the stand-
ard equipment, interposing the insulating gasket 3).
5.6 Positioning the probe - electrode
Before installing the burner on the generator, make sure the
probe and electrode are placed correctly as in Fig. 6.
5.7 Positioning the diaphragm (LPG operation)
The burner is supplied to operate with methane gas (G20)
A diaphragm 4)(Fig. 7) (RX25 = mm 6 e RX70 = mm 5.7) sup-
plied with the kit, allows burners to operate on LPG (G31) if fitted
to the gas valve 1).
The diaphragm must be installed in compliance with local laws
and regulations. .
To carry out the modification:
cut off the electrical supply;
close the fuel interception tap;
disassemble the gas valve 1) from the Venturi unit 2) by
removing the screws 3);
house the diaphragm 4) supplied with the kit in the
gasket 5);
reassemble the gas valve and carry out all the adjustment
operations described above.
1
23
Fig. 5
D10761
WARNING
Do not turn the electrode: position it as illustrated.
Placing the electrode near the ionisation probe
may result in the control box amplifier being dam-
aged.
137
151
15
±1
4.5
+0.5
0
Fig. 6
D7236
1
2
3
4
5
D8564
Fig. 7

11 20030020
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Installation
5.8 Fuel supply
The burners are teamed with one-piece pneumatic proportioning
gas valves, via which the amount of gas delivered, and hence the
output produced, can be modulated.
A signal reporting pressure detected in the air circuit is carried to
the pneumatic gas valve, which delivers an amount of gas in pro-
portion to the airflow produced by the fan.
To optimise the bulk, the gas train is assembled directly on the
body of the burner.
5.8.1 Gas train assembly
The connection valve-manifold allows compensating the acci-
dental occlusion of the suction line through the distributed gas re-
duction.
Air/gas mixer
Gas and combustive air are mixed inside the purging circuit (mix-
er), starting from the intake inlet.
Through the gas train, fuel is introduced into the intake air current
and optimal mixing commences with the aid of a mixer.
5.8.2 Gas valve
GAS TRAIN ASSEMBLY
D7375
D7155 D7380
Air/gas mixer
in the suction line circuit
Gas supply
Gas pressure downline
test point (P1)
Gas pressure downline
test point (P2)
Flange Gas valve
Minimum gas flow
adjustment (V1)
Minimum gas flow
adjustment on the stabiliser (V2)
D7376
Gas compensation pipe
Fig. 8
Valve model Honeywell VK4125V 2003 4
Mixer model Honeywell 45.900.444-001B
Gas line connection 1/2” inlet
Working temperature -15°C/70°C
Max. working pressure 30 mbar
Min. working pressure 15 mbar
Max. inlet pressure 60 mbar
Valve class B + B
Electrical supply 220-240 V
Protection level IP 40 according to IEC 529

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Installation
5.8.3 Testing
Check the standby of the burner by opening the thermostats (TL);
check that the burner is blocked while is working by opening
the connector (CN)inserted in the probe red wire and located out-
side the control box.
5.8.4 Ionisation current
The minimum current necessary for the control box operation is
5 µA. The burner normally supplies a higher current value, so that
no check is needed.
Anyway, if you want to measure the ionisation current, you need
to open the connector (CN1) fitted on the red wire and insert a
microammeter.
Optimum calibration values
MIN. output MAX. output
CO2(%) O2(%) CO2(%) O2(%)
METHANE 8 6.6 9 4.9
LPG 9.5 6.4 10 5.6
Probe
Connector
Control box
D5006
Fig. 9

13 20030020
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Operation
6.1 Notes on safety for the first start-up
6.2 Adjustments prior to ignition
The following adjustments must be carried out:
Open manual valves upline from the gas train.
Bleed the air from the gas line using the screw on the socket
START.
Check the trimmer settings on the control box (Fig. 10).
6.3 Burner start-up
Close the thermostat and switch on the burner's power.
The burner starts up under pre-purging conditions to the START
and the ignition occurs.
If the fan starts up, but no flame appears by the end of the safety
time, the control box allows the start-up programme to be repeat-
ed up to 3 times.
If ignition does not occur upon the third attempt, the burner goes
into lockout mode. Reset and wait for a new start-up attempt.
If ignition is still not achieved, it may be that gas is not reaching
the combustion head within the safety time period of 5 seconds.
Turn the screw V1 on the gas valve mixer slightly anticlockwise.
Once the burner has ignited, proceed with the global adjustment
of the burner.
6.4 Fan adjustment
Modulation is based on variable-speed technology.
Combustion air delivery can be adjusted by varying the motor's
speed (rpm).
The proportioning gas train delivers the right amount of fuel, de-
pending on the pressure detected in the purging circuit.
Hence the output delivered is adjusted by varying the motor's
speed of rotation.
The speed of the motor can be adjusted by means of three “Trim-
mers” (Fig. 10).
6 Operation
WARNING
The first start-up of the burner must be carried out
by qualified personnel, as indicated in this manual
and in compliance with the standards and regula-
tions of the laws in force.
WARNING
Check the correct working of the adjustment, com-
mand and safety devices.
Fig. 10
D10762

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Operation
6.5 Gas valve adjustment
The adjustment of the output of gas is achieved by using the two
screws V1 and V2 (Fig. 11).
To alter the maximum output of gas act on the screw V1.
– To increase the output: turn the screw V1 anticlockwise (un-
screw).
– To reduce the output: turn the screw clockwise (tighten).
To alter the minimum output of gas act on the screw V2 on the
gas valve. Remove the protection screw and act on the intern
screws with a hex key.
– To increase the output: turn the screw clockwise (tighten)
– To reduce the output: turn the screw anticlockwise (unscrew)
Definition of the adjustment for the fan:
The adjustments are carried out means on three potentiometers
on board of the motor control box.
START determine the air during the start
MIN determine the minimum modulation
MAX determine the maximum modulation
The adjustment of “MIN” takes place outright at finishing the pre-
purging outlined by the valve opening and by the presence of the
discharge.
The authorisation to the maximum modulation with “MAX” occurs
about 10 sec by the valve opening.
6.6 Burner adjustment
To achieve optimal burner adjustment, the flue gases produced
by combustion must be analysed as they leave the generator. In
conformity with Efficiency Directive 92/42/EEC, the burner must
be applied to the generator, adjusted and tested in compliance
with the instruction manual of the generator in question, including
checking of CO and CO2concentration in flue gases and their
temperature.
Check in this order:
– second stage output
– first stage output
– start-up output.
6.6.1 Second stage output
The second stage output power should coincide with that re-
quested by the generator used.
To increase or decrease its value, adjust trimmer MAX on the
control box.
Measure the gas delivery on the contactor to precisely establish
the burnt output.
Using a smoke analyser measure the value of the CO2or the O2
in order to optimise the burner calibration.
The correct values are:
To correct these values act on the gas valve in the following way:
– to increase the gas delivery and the CO2: turn the V1 screw
anticlockwise (loosen).
– to reduce the gas delivery and the CO2: turn the V1 screw
clockwise (tighten).
6.6.2 First stage output
The first stage output power should coincide with that requested
by the generator used.
To increase or decrease its value, adjust trimmer MIN on the con-
trol box.
Measure the gas delivery on the contactor to precisely establish
the burnt output.
Using a smoke analyser, measure the value of the CO2or the O2
in order to optimise the burner calibration.
The correct values are:
To correct these values act on thee gas valve in the following
way:
– to increase the gas delivery and the CO2: turn the screw V2
in a clockwise direction (screw up).
– to reduce the gas delivery and the CO2: turn the screw V2 in
an anticlockwise direction (unscrew).
Fig. 11
D7375
Minimum gas flow adjustment
Maximum gas flow adjustment (V1)
on the stabiliser (V2)
CO2O2
G20 (methane) 8 - 9% 5 - 5.5%
G31 (LPG) 10 - 10.7% 5.7 - 6.2 %
CO2O2
G20 (methane) 8 - 9% 5 - 5.5%
G31 (LPG) 10 - 10.7% 5.7 - 6.2 %

15 20030020
GB
Operation
6.6.3 Start-up output
The start-up output can be varied by means of the START trim-
mer located on the equipment.
The table below gives the possible settings for a generator.
6.7 Combustion head
The combustion head comprises a highly thermal resistant cylin-
der whose surface features numerous holes, encased in a metal
"mesh" (Fig. 12).
The air-gas mixture is pushed inside the cylinder and out of the
head through the holes in the perimeter.
Combustion starts when the air-gas mixture is ignited by a spark
generated by the electrode.
The metal "mesh" is the combustion head's most essential ele-
ment since it improves burner performance considerably.
The flame developed on the surface of the head is perfectly re-
tained and adheres to the mesh when operating at the maximum
setting.
This allows modulating ratios as high as 6:1, avoiding the danger
of flashback when modulating is at its minimum.
The flame features an extremely compact geometry, meaning
that there is no risk of contact between the flame and parts of the
generator, consequently eliminating the possible problem of poor
combustion.
The flame's structure means that smaller combustion chambers
can be developed, designed to exploit this particular feature.
6.8 Emissions
The emission values of the burners are much lower than the limits
laid down by the strictest standards.
The flame's distribution and its spread over a large surface
means that the burner manages to limit the formation of ther-
mal NOx, the main causes of pollutant emission.
Stage Output (kW) Min. speed
(rpm) CO2(%) Trimmer setting
RX25 RX70 RX25 RX70 RX25 RX70 RX25 RX70
Second 25 33 5200 4600 8 - 9% 4,5 3
First 12 18 2250 2650 8 - 9% 3,5 4,5
Start 14 33 2700 4550 8 - 9% 2 10
Fig. 12
D9714
mg/kWh
NOx CO
NOx
CO
CLASS 3 LIMIT = 80 mg/kWh
70
60
50
40
30
20
10
0
Fig. 13
Minimum
modulation 7 kW Maximum modulation 35 kW

20030020 16
GB
Operation
6.9 Operating programme
6.9.1 Normal operation
Operating times
Time expressed in seconds
ts
t3t2
tw t1 tm
TL
M
I
V
SO
LED
P
M
SO
.
tf
D10632
Red (LED signalling)
No signal needs to be received
Fig. 14
Key
I– Ignition transformer
LED – Reset button LED indicating operating status
M–Fanmotor
SO – Ionisation probe
TL – Limit thermostat
V– Gas valve
Lockout
Flame loss during the operation
and lockout due to ignition failure
ta tf tl tm ts tw t1 t2 t3 t8
20140105 -403 510
ta Time for checking motor turns:
if the number of turns is lower than 900 rpm, after ta will
be carried out a lockout. tw Stabilisation time motor turns.
tf Response time after the flame disappearance. t1 Pre-purging time:
by the signal of heat request to the end of the ignition.
tl Flame or flame simulation detected during pre-purging:
immediate lockout. t2 Transformer pre-ignition time: ignition before the valve closing.
tm Stabilisation time:
the modulation occurs after this time. t3 Transformer ignition time: the transformer remains on during the safety time.
ts Safety time: if at the end of the time ts a flame is not present, tpp is
carried out. After 3 times follows a lockout. t8
Post-purging time:
Additional purging when the heat request is completed,
or in case of flame failure during the operation or in
case of ignition failure.

17 20030020
GB
Operation
6.9.2 Lockout due to ignition failure
6.9.3 Lockout due to a flame or flame simulation detected during pre-purging
Lockout types and triggering times in case of burner mal-
function
6.10 Recycle function if flame goes out during operation
The control box allows recycling, i.e. the complete repetition of
the start/up program.
If after the safety time since the last recycle the flame does not
appear, the burner carries out a lockout.
D7253
ts
t3
t1
t2
tw
TL
M
I
V
SO
LED
P
M
.
D10631
Lockout at 3th
re-ignition
Red (LED signalling)
Fig. 15
ts
t1tw
TL
M
I
V
SO
LED
P
M
.
Key
I– Ignition transformer
LED – Reset button LED indicating operating
status
M–Fanmotor
SO – Ionisation probe
TL – Limit thermostat
V– Gas valve
Red (LED signalling)
D10633
Lockout
Fig. 16
Description of types of faults Lockout
Presence of flame in pre-purging “t1” At the end of the time of “t1”
No ignition at end of safety time “ts” After max. 3 repeats, within 1 second
Flame goes out during operation After max. 1 repetition, if there is no flame at the end of ts
Not correct No. of turns of the fan motor (< 900 rpm) After max. 20 seconds
Fault at the valve circuit At the end of the time of “t1”

20030020 18
GB
Operation
6.11 Restart function following firing failure
The control box allows the start-up programme to be repeated,
making up to 3 attempts, if no flame is formed by the end of the
safety time.
If the flame still fails to appear after the fourth ignition attempt, the
burner locks out at the end of the safety time.
6.12 Control of the motor rpm
Check of the motor operation if the rotation number per minimum
minute exceeds (900 rpm).
If the motor does not exceed the number of minimum turns, it
stops after 20 seconds.
6.13 Control box reset (using built-in button)
To carry out the control box reset, proceed as follows:
Press and hold the reset button for 1-2 seconds.
In case the burner does not restart it is necessary to check if
the limit thermostat (TL) is closed.
6.14 Control box reset (using remote connection)
The terminal board XMB has an input RS provided for the remote
resetting of the control box.