Riello 908T4 Quick start guide

20160576 (2) - 02/2020
Installation, use and maintenance instructions
Premix gas burners
Modulating operation with pilot flame ignition
CODE MODEL TYPE
20160021 RX 180 S/PV 908T4
20160022 RX 250 S/PV 903T4
GB

Translation of the original instructions

1 20160576
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Contents
1 Declarations................................................................................................................................................................................ 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 Other symbols................................................................................................................................................................. 4
2.1.4 Delivery of the system and the instruction manual ......................................................................................................... 5
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 Burner categories - Countries of destination .................................................................................................................. 7
4.3 Burner equipment ........................................................................................................................................................... 7
4.4 Technical data ................................................................................................................................................................ 8
4.5 Electrical data ................................................................................................................................................................. 8
4.6 Maximum dimensions ..................................................................................................................................................... 9
4.7 Burner description......................................................................................................................................................... 10
4.8 Combustion head.......................................................................................................................................................... 10
4.9 Firing rates (version TC) ............................................................................................................................................... 11
4.10 Test boiler ..................................................................................................................................................................... 11
4.11 Delivered output (version TC)....................................................................................................................................... 12
4.12 Adjustment pilot ............................................................................................................................................................ 13
4.13 Burner controls (LME71... with PME71.901...) ............................................................................................................. 15
4.13.1 Indication of the diagnostic mode ................................................................................................................................. 20
5 Installation ................................................................................................................................................................................ 21
5.1 Notes on safety for the installation................................................................................................................................ 21
5.2 Handling........................................................................................................................................................................ 21
5.3 Preliminary checks........................................................................................................................................................ 21
5.4 Operating position......................................................................................................................................................... 22
5.5 Preparing the boiler ...................................................................................................................................................... 22
5.5.1 Boring the boiler plate................................................................................................................................................... 22
5.5.2 Head length .................................................................................................................................................................. 22
5.6 Fixing of the combustion head, electrodes assembly and the gas valve (version TC) ................................................. 23
5.7 Securing the burner to the boiler .................................................................................................................................. 24
5.8 Fuel supply ................................................................................................................................................................... 25
5.8.1 Air/gas mixer................................................................................................................................................................. 25
5.8.2 Gas train ....................................................................................................................................................................... 26
5.9 Electrical wiring............................................................................................................................................................. 27
5.9.1 Supply cables and external connections passage........................................................................................................ 27
5.9.2 Opening sequence of the fuse-holder........................................................................................................................... 28
6 Calibration and operation........................................................................................................................................................ 29
6.1 Operator panel with LCD AZL 21... display for control box LME 71... with PME 71.901... ........................................... 29
6.2 Operator panel with LCD display.................................................................................................................................. 30
6.3 Visualisation and programming modes......................................................................................................................... 31
6.3.1 Operation ...................................................................................................................................................................... 31
6.3.2 Displaying the operating position.................................................................................................................................. 32
6.3.3 Fault messages, display errors and information ........................................................................................................... 32
6.4 Info level ....................................................................................................................................................................... 33
6.4.1 Displaying the Info level................................................................................................................................................ 33
6.5 Displaying the Info values............................................................................................................................................. 34
6.5.1 Identification date.......................................................................................................................................................... 34

20160576 2
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Contents
6.5.2 Identification number .....................................................................................................................................................34
6.5.3 Burner identification.......................................................................................................................................................35
6.5.4 Number of resettable start-ups......................................................................................................................................35
6.5.5 Total number of start-ups ..............................................................................................................................................36
6.5.6 End of the Info level.......................................................................................................................................................36
6.6 Service level ..................................................................................................................................................................37
6.6.1 Displaying the Service values .......................................................................................................................................38
6.7 Parameters level ...........................................................................................................................................................39
6.7.1 Entering the password...................................................................................................................................................40
6.7.2 Backup ..........................................................................................................................................................................41
6.7.3 Restore..........................................................................................................................................................................42
6.8 Parameter modes of operation......................................................................................................................................44
6.8.1 Parameters without index, with direct display ...............................................................................................................44
6.8.2 Parameters without index, without direct display ..........................................................................................................45
6.8.3 Parameters with index, with or without direct display ....................................................................................................47
7 Start-up, calibration and operation of the burner ..................................................................................................................49
7.1 Notes on safety for the first start-up ..............................................................................................................................49
7.2 Adjustments prior to ignition ..........................................................................................................................................49
7.3 Fan adjustment..............................................................................................................................................................49
7.4 Pre-setting of the points P0 (ignition), P1 (minimum) and P2 (maximum).....................................................................49
7.5 Burner start-up ..............................................................................................................................................................50
7.5.1 First burner start-up (manual operation)........................................................................................................................50
7.5.2 Checking the modulating operation (automatic operation)............................................................................................51
7.6 Combustion head ..........................................................................................................................................................52
7.7 Burner adjustment .........................................................................................................................................................52
7.7.1 Indicative calibration values ..........................................................................................................................................52
7.7.2 Emissions ......................................................................................................................................................................52
7.8 Switching off the burner.................................................................................................................................................53
7.9 Load controller inputs ....................................................................................................................................................53
7.10 Final checks (with burner operating) .............................................................................................................................53
8 Maintenance ..............................................................................................................................................................................54
8.1 Notes on safety for the maintenance.............................................................................................................................54
8.2 Maintenance programme ..............................................................................................................................................54
8.2.1 Maintenance frequency .................................................................................................................................................54
8.2.2 Safety test - with gas feeding closed.............................................................................................................................54
8.2.3 Checking and cleaning ..................................................................................................................................................54
8.2.4 Safety components........................................................................................................................................................55
8.3 Opening and closing the burner ....................................................................................................................................55
8.4 Recommended preventive maintenance programme ...................................................................................................56
9 Operation, indications, diagnostic ..........................................................................................................................................57
9.1 Control sequence in the event of a fault ........................................................................................................................57
9.2 List of error codes with operation using AZL21 Display ... ............................................................................................58
9.3 Resetting of burner control ............................................................................................................................................59
9.3.1 Diagnostics of the cause of the fault .............................................................................................................................59
9.3.2 Before starting with a new program module or when the program module is replaced.................................................60
9.4 Manual reset..................................................................................................................................................................61
9.4.1 Error during the reset process.......................................................................................................................................62
9.4.2 Reset .............................................................................................................................................................................62
10 List of parameters PME71.901... ..............................................................................................................................................63
A Appendix - Accessories ...........................................................................................................................................................66
B Appendix - Electrical panel layout...........................................................................................................................................67

3 20160576
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Declarations
1 Declarations
Declaration of Conformity in accordance with ISO / IEC 17050-1
Manufacturer: RIELLO S.p.A.
Address: Via Pilade Riello, 7
37045 Legnago (VR)
Product: Premix gas burners
Model and type RX 180 S/PV 908T4
RX 250 S/PV 903T4
These products are in compliance with the following Technical Standards:
EN 676
EN 12100
and according to the European Directives:
GAR 2016/426/EU Gas Appliances Regulation
MD 2006/42/CE Machine Directive
LVD 2014/35/EU Low Voltage Directive
EMC 2014/30/EU Electromagnetic Compatibility
The products are marked as follows:
The quality is guaranteed by a quality and management system certified in accordance with ISO 9001:2015.
Legnago, 21.04.2018 Executive General Manager
RIELLO S.p.A. - Burner Department
Research & Development Director
RIELLO S.p.A. - Burner Department
Mr. U. Ferretti Mr. F. Comencini
CE-0123CT1618 Classe 3 (EN 676)

20160576 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 Ser-
vice 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 Other symbols
Abbreviations used
Ch. Chapter
Fig. Figure
Page Page
Sec. Section
Tab. Table
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
DANGER: LIVE COMPONENTS
This symbol indicates operations which, if not car-
ried out correctly, lead to electric shocks with le-
thal consequences.
DANGER: FLAMMABLE MATERIAL
This symbol indicates the presence of flammable
materials.
DANGER: BURNING
This symbol indicates the risks of burns due to
high temperatures.
DANGER: CRUSHING OF LIMBS
This symbol indicates the presence of moving
parts: danger of crushing of limbs.
WARNING: MOVING PARTS
This symbol indicates that you must keep limbs
away from moving mechanical parts; danger of
crushing.
DANGER: EXPLOSION
This symbol signals places where an explosive at-
mosphere may be present. An explosive atmos-
phere is defined as a mixture - under atmospheric
conditions - of air and flammable substances in
the form of gases, vapours, mist or dust in which,
after ignition has occurred, combustion spreads to
the entire unburned mixture.
PERSONAL PROTECTION EQUIPMENT
These symbols indicate the equipment that must
be worn and kept by the operator for protection
against threats against safety and/or health while
at work.
OBLIGATION TO ASSEMBLE THE COVER
AND ALL THE SAFETY AND PROTECTION DE-
VICES
This symbol signals the obligation to reassemble
the cover and all the safety and protection devices
of the burner after any maintenance, cleaning or
checking operations.
ENVIRONMENTAL PROTECTION
This symbol gives indications for the use of the
machine with respect for the environment.
IMPORTANT INFORMATION
This symbol indicates important information that
you must bear in mind.
This symbol indicates a list.

5 20160576
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Information and general warnings
2.1.4 Delivery of the system and the instruction
manual
When the system is delivered, it is important that:
the instruction manual is delivered 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 Assis-
tance Centre
The system supplier must carefully inform the user about:
– the use of the system;
– any further tests that may be required before activating
the system;
– maintenance, and the need to have the system checked
at least once a year by a representative of the manufac-
turer or another specialised technician.
To ensure a periodic check, the manufacturer recom-
mends the drawing up of a Maintenance Contract.
2.2 Guarantee and responsibility
The manufacturer guarantees its new products from the date of
installation, 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 unauthorised modifications on the equipment;
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 supply system;
continuation of use of the burner when a fault has occurred;
repairs and/or overhauls incorrectly carried out;
modification of the combustion chamber with inserts that
prevent the regular development of the structurally estab-
lished flame;
insufficient and inappropriate surveillance and care of those
burner components most likely to be subject to wear and
tear;
use of non-original components, including spare parts, kits,
accessories and optional;
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 carrying out of non authorised modifica-
tions will result in the annulment by the
manufacturer of the guarantee that it supplies with
the burner.

20160576 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 uses expressly foreseen by the manufactur-
er;
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;
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;
Personnel must observe all the danger and caution indica-
tions shown on the machine.
Personnel must not carry out, on their own initiative, opera-
tions or interventions that are not within their province.
Personnel must 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 every responsibility for any damage that
may be caused by the use of non-original parts.
In addition:
3 Safety and prevention
WARNING
The manufacturer guarantees safety and proper
functioning only if all burner components are intact
and positioned correctly.
must take all the measures necessary to pre-
vent unauthorised people gaining access to
the machine;
the user must inform the manufacturer if
faults or malfunctioning of the accident pre-
vention systems are noticed, along with any
presumed danger situation;
personnel must always use the personal pro-
tective equipment envisaged by legislation
and follow the indications given in this man-
ual.

7 20160576
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Technical description of the burner
4.1 Models available
4.2 Burner categories - Countries of destination
Tab. A
4.3 Burner equipment
Flange for gas train . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . No. 1
Air intake . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . No. 1
Gas pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . No. 1
Screws M 5 x 16 for securing the valve . . . . . . . . . . . . . . . No. 4
Insulating screen and gasket . . . . . . . . . . . . . . . . . . . . . . . No. 1
Gas valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . No. 1
2-pin plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . No. 1
4-pin plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . No. 1
7-pin plug. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . No. 1
Small parts unit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . No. 1
Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . No. 1
Spare parts list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . No. 1
Hardware for burner assembly:
8 x 50 zinc-plated nuts (with or without tip). . . . . . . . . . . . . No. 4
Zinc-plated washers Ø 8. . . . . . . . . . . . . . . . . . . . . . . . . . . No. 4
Zinc-plated toothed washers Ø 8 . . . . . . . . . . . . . . . . . . . . No. 4
M8 Zinc-plated nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . No. 4
4 Technical description of the burner
Designation Voltage Code
RX 180 S/PV 230V - 50-60 Hz 20160021
RX 250 S/PV 230V - 50-60 Hz 20160022
Country of destination Gas category
AT - CH - CZ - ES - FR - GB - GR - HR - IE - IS - IT - LT - PT - RO - SI - SK II2H3P
DE - PL I2E, I3P
NL II2EK3P
HU I2H, I3P
BE I2E(R), I3P
LU I2E
BG - DK - EE - FI - LV - NO - SE I2H
CY - MT I3P
WARNING
The burner is supplied with combustion head and
electrodes assembled.

20160576 8
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Technical description of the burner
4.4 Technical data
Tab. B
(1) Reference conditions: Ambient temperature 20°C - Gas temperature 15°C - Barometric pressure 1,013 mbar - Altitude 0 m a.s.l.
(2) Input gas pressure 8)(Fig. 3) with zero pressure in combustion chamber and at maximum burner output.
(3) Sound pressure measured in manufacturer's combustion laboratory, with burner operating on test boiler, at maximum, average and minimum mod-
ulation output. The sound power is measured with the “Free Field” method, as per EN 15036, and according to an accurate “Accuracy: Category 3”
measurement, as described in EN ISO 3746.
4.5 Electrical data
Tab. C
Model RX 180 S/PV RX 250 S/PV
Type 908T4 903T4
Output (1)
Delivery (1) min - max
min - max
kW
Mcal/h
GAS LPG GAS LPG
30 ÷ 180
26 ÷ 155
36 ÷ 180
31 ÷ 155
42 ÷ 250
36 ÷ 215
50 ÷ 250
43 ÷ 215
Fuel Natural gas: G20 (Natural gas), G25 - LPG: (G31)
Supply pressure (2) mbar 15 ÷ 100 (G20)
29 ÷ 100 (G31)
Diameter gas valve inlet 1”
Operation – Intermittent (min. 1 stop in 24 hours).
– Modulating.
Standard applications Boilers: water, steam, diathermic oil
Ambient temperature °C 0 - 50
Combustion air temperature °C max 60
Weight kg 30
Noise level (3) Sound pressure
Sound power dB(A) 39.7 51.6
72.8
84.7
Model RX 180 S/PV RX 250 S/PV
Type 908T4 903T4
Auxiliary circuit electrical supply 1N~ 230V~ +/-10% 50/60 Hz
Electrical supply 1N~ 230V~ +/-10% 50/60 Hz
Fan motor rpm
kW
V
A
5830
0.36
230 V 50/60 Hz
1.6
Ignition transformer V1 - V2
I1 - I2
230 V - 2 x 10 kV
0.3 A - 50/60 Hz - 40 mA
Absorbed electrical power kW max 0.53
Protection level IP40

9 20160576
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Technical description of the burner
4.6 Maximum dimensions
The maximum dimensions of the burner and flange are shown in
Fig. 1.
Tab. D
Tab. E
Fig. 1
L
H
T
TX
D
E
P
20160386
mm H L P T TX D E
RX 180-250 S/PV 390 640 503 465 320 119 306
mm A B C
RX 180-250 S/PV 1218 564 485
D88
Fig. 2

20160576 10
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Technical description of the burner
4.7 Burner description
4.8 Combustion head
1 Ignition electrode
2 Flame sensor probe
3 Gas valve
4 Air/gas mixer in the suction line circuit
5 Gas pressure test point
6 Gas valve conduit - Venturi
7 Gas input
8 Boiler fixing flange
9Fan
10 Air passage in fan
11 Control box
12 Programming card
13 Plug-socket on ionisation probe cable
14 Gas train pilot
15 Transformer
16 Plate with four hole knock-outs for electrical cable routing
17 Reset button
18 7 pin plug
19 Fuses
20 4 pin plug
21 6 pin plug
22 Display
23 Timers
Burner lockout may occur.
control box lockout:
if the control box 13)(Fig. 3) push-button lights up, it indicates
that the burner is in lockout.to reset, press the push-button.
15 18
24
13
6
4
8
719 16 21 17
12
9
23 10 14
22
3
12
11
5
20
Fig. 3
20160380

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Technical description of the burner
4.9 Firing rates (version TC)
The MAXIMUM OUTPUT must not be greater than the maximum
limit of the diagram.
RX 180 S/PV = 180 KW G20 - G25 - G31
RX 250 S/PV = 250 KW G20 - G25 - G31
The MINIMUM OUTPUT must not be lower than the minimum
limit of the diagram.
RX 180 S/PV = 30 KW G20 - G25
= 35 KW G31
RX 250 S/PV = 42 KW G20 - G25
= 50 KW G31
The IGNITION OUTPUT must be selected within:
– area A for gas G20 - G25;
– area B for gas G30 - G31.
4.10 Test boiler
The firing rates were set in relation to special test boilers, accord-
ing to EN 676 regulations.
The burner-boiler combination does not pose any problems if the
boiler is EC type-approved.
If, however, the burner is to be used with a commercial boiler that
has not been EC approved and/or its combustion chamber di-
mensions are distinctly smaller, consult the manufacturer.
It is not advisable to use this burner for boilers with a frontal cir-
culation of the flue gases.
WARNING
The firing rate (Fig. 4) has been obtained at an
ambient temperature of 20°C, at a barometric
pressure of 1013 mbar (about 0 m a.s.l.).
A
A
B
B
Heat output - kW
RX 180 S/PV
RX 250 S/PV
Firing rate G20-G25 Firing rate G31
Firing rate G20-G25 Firing rate G31
20160389
Heat output - kW
Fig. 4
Pressure in
combustion chamber - mbar
Pressure in
combustion chamber - mbar

20160576 12
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Technical description of the burner
4.11 Delivered output (version TC)
The diagrams opposite allow you to set the power output either
using the number of fan revs or using the pressure downstream
of the gas valve (point 1).
Example:
• operation with Premix RX 250 S/PV;
• natural gas G20 NCV 9.45 kWh/Sm3;
• pressure on point 1 = -21 mbar.
The burnt output corresponds to 200 kW.
Going vertically up the diagram, to intersect the dotted line, you
can estimate the value of the number of revs on the left hand y-
axis: in this case 4750 rpm. For an exact reading of the number
of revs there is a kit for interfacing with the control box.
NOTE:
A different adjustment of the gas valve is required for LPG
operation.
RX180S/ PV G20- G25
RX180S/ PV G30- G31
RX250S/ PV G20- G25
RX250S/ PV G30- G31
No. of motor turns/min.
No. of motor turns/min.
No. of motor turns/min.
No. of motor turns/min.
Heat output – kW
Heat output – kW
Heat output – kW
Heat output – kW
Pressure outlet gas valve - mbarPressure outlet gas valve - mbar
Pressure outlet gas valve - mbar
RX 180 S/PV G20 - G25
RX 180 S/PV G31
RX 250 S/PV G20 - G25
RX 250 S/PV G31
Pressure outlet gas valve - mbar
D7814
No. revs
Pressure
Fig. 5

13 20160576
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Technical description of the burner
4.12 Adjustment pilot
The diagrams allow to choose the optimal gas pressure at the pi-
lot according to the revolutions at the ignition (PO) and the CO2
to which you want to calibrate it.
The pressure test point to be used is shown in Fig. 6.
S9796
Fig. 6
Pilot
pressure
test point
Pressure
adjuster
20160391
RX 180/PV G20
RX 180/PV GPL
RX 180/PV G25
Pressure outlet gas pilot - mbar
No. of motor turns/min.
Pressure outlet gas pilot - mbarPressure outlet gas pilot - mbar
No. of motor turns/min.
No. of motor turns/min. Fig. 7

20160576 14
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Technical description of the burner
RX 250/PV GPL
RX 250/PV G25
Pressure outlet gas pilot - mbar
No. of motor turns/min.
Pressure outlet gas pilot - mbarPressure outlet gas pilot - mbar
No. of motor turns/min.
No. of motor turns/min.
RX 250/PV G20 20160394
Fig. 8

15 20160576
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Technical description of the burner
4.13 Burner controls (LME71... with PME71.901...)
Warnings
All the operations (assembly, installation, maintenance, etc.)
should be carried out by qualified personnel.
Before modifying the wiring in the connection area, fully dis-
connect the system from the power supply (omnipolar sepa-
ration). Check the system is not powered and cannot be
inadvertently restarted. Failure to do this will lead to the risk
of electrocution.
Ensure protection against the risks of electrocution by pro-
viding adequate protection at the terminal connection of the
burner (for example, using blind terminals for the inputs and
the unused outputs). Failure to do this will lead to the risk of
electrocution.
The space where the program module is placed (Fig. 10) is
defined as a connection area and is therefore protected
against accidental contact when the module is not present.
If the housing or the area next to the operator panel is dam-
aged, the unit should be immediately switched off. Failure to
do this will lead to the risk of electrocution.
Press the operator panel buttons only with your hands, with-
out using any equipment or pointed objects. Damage to the
operator panel fill leads to the risk of electrocution.
To ensure the safety and reliability of the LME71... system, the
following instructions must also be followed:
– Avoid conditions which may promote condensation and hu-
midity.
Otherwise, before switching on again, make sure that the en-
tire control box is perfectly dry! Failure to do this will lead to
the risk of electrocution.
– Static charges must be avoided since they can damage the
control box’s electronic components when touched.
Program module
Assembly notes
Make sure that the relevant national safety standards are
respected
The standard LME7 unit should be fixed with M4 (UNC32) or
M5 (UNC24) fixing screws, respecting a maximum tightening
torque of 1.8 Nm and using all 3 fixing points.
The additional assembly surfaces of the housing have the
purpose of improving the mechanical stability.
The should rest on the assembly surface to which the unit is
fixed.
The planarity of the assembly surface should be within a tol-
erance range of 0.3 mm.
WARNING
To avoid accidents, material or environmental
damage, observe the following instructions!
The LME71... are safety devices! Avoid opening
or modifying it, or forcing its operation.
Riello S.p.A. cannot assume any responsibility for
damage resulting from unauthorised interven-
tions! Also the safety notes contained in other
chapters of this document must be respected!
WARNING
The installation and operation of the machine
should be carried out only by qualified personnel.
For the purposes of the safety notes in this docu-
ment, by qualified personnel is meant people au-
thorised to commission, ground and identify
electric devices, systems circuits conforming to
safety practices and norms.
WARNING
The formation of condensation, ice and the infiltra-
tion of water must absolutely be avoided!
Otherwise, the safety functions could be compro-
mise leading to a risk of electrocution.
S8593
Fig. 9
S8673
Fig. 10

20160576 16
GB
Technical description of the burner
Installation notes
Arrange the high voltage ignition cables separately, as far as
possible from the control box and the other cables.
Do not confuse the powered conductors with the neutral
ones.
Install the switches, fuses and grounding in compliance with
local regulations.
The connection diagrams show the burner controls with
grounded neutral conductor.
Make sure that the maximum admissible current of the termi-
nal connections is not exceeded.
Make sure the cable grommets of the connected cables
comply with the relevant standards.
Do not supply mains voltage to the control box outputs. Dur-
ing the testing of the devices controlled from the burner con-
trol (fuel valve, etc), the LME71… should not be connected
to the units.
The mechanical connection between the actuators and the
fuel and air control elements, or any other type, should be
rigid.
Make sure there are no short-circuits on the air pressure
switch connection lines.
Electrical wiring to the flame detectors
It is important for signal transmission to be practically free of any
disturbances or loss:
Always separate the detector cables from the other cables:
– the capacitive reactance of the line reduces the magnitude
of the flame signal;
– use a separate cable.
Respect the permitted lengths for the cables of the detectors
(see Technical Data).
The ionisation probe powered from the mains is not pro-
tected from the risk of electric shocks.
Position the ignition electrode and the ionisation probe so
that the ignition spark cannot form an arc on the probe (risk
of electric overload) and that it cannot negatively effect the
supervision of the ionisation.
Description of displays and buttons
Tab. F
Button Function
Button A
– Displaying default output
– In lockout position: output value at the time of
the fault
Enter and Info button
The reset button (info button) is the key element
for resetting the burner control and activating/de-
activating the diagnostic functions.
Button -
– Displaying flame 2 signal current or display-
ing phases
– In lockout position: MMI phase at the time of
the fault
Button +
– Displaying flame 1 signal current or display-
ing phases
– In lockout position: MMI phase at the time of
the fault
Warning light with 3 colours
The warning light with three colours (red - yellow
- green) is the key indicator of the visual diagnos-
tics.
Button + and -: escape function
Press the + and - buttons at the same time!
– No adoption of value
– Access to a higher menu level
– Keep pressed for >1 second for the backup/
reset function
nfo
+
-
A
S8595
Fig. 11
A
nfo
-
+
- +
and

17 20160576
GB
Technical description of the burner
Technical data
Tab. G
Burner controls
LME71...
Mains voltage AC 230 V
Mains frequency 50 / 60 Hz +- 6%
Power absorption <10 W, normally
Primary external fuse Max. 6.3 A (slow)
Safety class I, with components in compliance with II and III, ac-
cording to DIN EN 60730-1
“Input” terminals
values
Voltage UMains 230 V
• If the mains voltage drops, the is a safety shut-
down from the operating position
• Restarting occurs when the mains voltage exceeds
< AC 165 V
> AC 195 V
Input currents and voltages
– UeMax
–UeMin
–IeMax
–IeMin
UN +10%
UN -15%
peak 1 mA (peak value)
peak 0.5 mA (peak value)
Voltage detection
–ON
–OFF
> AC 120 V
< AC 80 V
“Output” terminals
Values
Total load on the contacts:
Nominal voltage
Input current X3-04 unit (safety loop) from:
– fan motor contact maker
– ignition transformer
– fuel valves
AC 230 V - 50/60 Hz
Max. 5 A
Individual contact rating:
Fan motor contact maker X2-01 foot 3
– Nominal voltage
– Nominal current
– Power factor
AC 230 V 50/60 Hz
2 A (15A max. 0.5 s)
Cos0.4
Alarm output X2-03/3
– Nominal voltage
– Nominal current
– Power factor
AC 230 V 50/60 Hz
1A
Cos> 0.6
Ignition transformer X4-02 foot 3
– Nominal voltage
– Nominal current
– Power factor
AC 230 V 50/60 Hz
2A
Cos> 0.4
Auxiliary output
– Nominal voltage
– Nominal current
– Power factor
AC 230 V 50/60 Hz
1A
Cos> 0.6
Output relay contact 2 foot 2 X2-09 foot 7
– Nominal voltage
– Nominal current
– Power factor
AC 230 V 50/60 Hz
1A
Cos> 0.4
Fuel valve/pilot valve X7-01 foot 3
– Nominal voltage
– Nominal current
– Power factor
AC 230 V 50/60 Hz
1A
Cos> 0.4
Safety valve X6-03 foot 3
– Nominal voltage
– Nominal current
– Power factor
AC 230 V 50/60 Hz
1.5 A
Cos> 0.6
Cable length Power supply line from the mains Max. 100 m (100 pF / m)
Sections The sections of the mains power supply lines (L, N, and PE) and, if necessary, the safety loop (safety limit
thermostat, lack of water, etc.) should be sized for the nominal currents according to the external primary fuse
selected. The sections of the other cables should be sized based on the fuse of the internal unit (max. 6.3 AT).
Environmental
conditions
Operation
Climatic conditions
Mechanical conditions
Temperature range
Humidity
DIN EN 60721-3-3
Class 3K3
Class 3M2
-40...+60°C
< 95% RH

20160576 18
GB
Technical description of the burner
Program sequence
M
Z
PV
V1+V2
AL
X2-02 Pin 3
Speed points
P2 (high-re)
P0 (ignition load)
P1 (low-re)
0 (no-load speed)
R
LR-OPEN
LR-CLOSE
Optional (LP)
if P235=1
Pmin
P LT
ION / QRA
Not active
X3-04 Pin 5
Relay
contact Function/inputs
Operating unit parameter number
LED permanent
LED ashing
tw t11 t10 t12 t3 t3n t4
Standby Startup
t1 TSA
432752622062522952
Relay
contact Function/outputs
SK
X3-04 Pin 1
X5-03 Pin 1
X5-03 Pin 3
X65 Pin 1
X5-03 Pin 2
X65 Pin 1
X3-02 Pin 1
X5-01 Pin 2
X2-02 Pin 4
X9-04 Pin 2
PWM
X6-03 Pin 3
X2-01 Pin 3
X4-02 Pin 3
X2-03 Pin 3
Phase number
0147274424048363030322422212 oP: xx (actual load in %) 74
224
t11 t8
POC
POC
Stand-by
speed
Prepurge speed
Ignition load speed
High-re speed
Modulation range
Low-re speed
Postpurge speed
240240240240240240
*1
*2
Operation Shutdown
S9220
Fig. 12