Riello 885 T80 Quick start guide

GB
Installation, use and maintenance instructions
Instrucciones de instalación, funcionamiento y mantenimiento
Instruções de Instalação, Funcionamento e Manutenção
Forced draught gas burner
E
Quemador de gas de aire soplado
P
Queimador a gás com ar insuflado
Two-stage progressive operation
Funcionamiento a dos llamas progresivas
Funcionamento a duas chamas progressivas
CODE - CÓDIGO MODEL - MODELO TYPE - TIPO
3789380 RS 64 MZ 885 T80
20033315 (7) - 02/2023

Declaration of Conformity in accordance with ISO / IEC 17050-1
These products are in compliance with the following Technical Standards:
• EN 12100
•EN676
According to the European Directives:
MD 2006/42/EC Machine Directive
LVD 2014/35/EU Low Voltage Directive
EMC 2014/30/EU Electromagnetic Compatibility
The quality is guaranteed by a quality and management system certified in accordance with ISO 9001:2015.

The following symbols are used in this manual:
ATTENTION = for actions requiring special care and adequate preparation.
FORBIDDEN = for actions THAT MUST NOT be performed.
!
IDENTIFICATION
The Identification Plate on the product gives the serial number, model and main technical and perfor-
mance data. If the Identification Plate is tampered with, removed or missing, the product cannot be
clearly identified, thus making any installation or maintenance work potentially dangerous.
GENERAL WARNINGS
The dimension of the boiler’s combustion chamber must respond to specific values, in order to guaran-
tee a combustion with the lowest polluting emissions rate.
You are therefore advised to consult the Technical Assistance Department before choosing this type of
burner for the combination with a boiler.
Qualified personnel are those with the professional and technical requirements indicated by Law no.
46 dated 5 March 1990. The commercial organisation has a widespread network of agencies and tech-
nical offices whose personnel participates periodically in instructional and refresher courses at the
company training centre.
This burner must only be used for the application it was designed for.
The manufacturer cannot accept responsibility for any damage to persons, animals or property due to
errors in installation or in the burner adjustment, or due to improper or unreasonable use or non-obser-
vance of the technical instructions enclosed with the burner, or due to the intervention of unqualified
personnel.
USER INFORMATION
If faults arise in ignition or operations, the burner performs a "safety stop", which is signalled by the
red burner lock out LED. To rearm start-up conditions, press the release button. When the burner
starts up again, the red LED goes out. 
This operation can be repeated for a maximum of 3 times. If the "safety stop" recurs, then the
Technical Assistance Centre must be contacted. 
BASIC SAFETY RULES
Children or inexpert persons must not use the appliance.
Under no circumstances must the intake grids, dissipation grids and ventilation vents in the installa-
tion room be covered up with cloths, paper or any other material.
Unauthorised persons must not attempt to repair the appliance
It is dangerous to pull or twist the electric leads.
Cleaning operations must not be performed if the appliance is not disconnected from the main power
supply.
Do not clean the burner or its parts with inflammable substances (e.g. petrol, alcohol, etc.).
The cover must be cleaned with soapy water.
Do not place anything on the burner.
Do not leave containers and inflammable products in the installation room.

GB
1
CONTENTS
TECHNICAL DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .page 2
Electrical data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Burner description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Packaging - Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Max. dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Standard equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Firing rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Test boiler. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Commercial boilers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Gas pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Boiler plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Blast tube length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Securing the burner to the boiler . . . . . . . . . . . . . . . . . . . . . . . . . 6
Combustion head setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Gas line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Adjustments prior to ignition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Servomotor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Burner starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Burner firing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Burner calibration: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
1 - Firing output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2 - 2nd stage output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3 - 1st stage output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
4 - Intermediate outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
5 - Air pressure switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
6 - Minimum gas pressure switch. . . . . . . . . . . . . . . . . . . . . . . . 12
Flame present check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Burner operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Final checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Safety test - with gas ball valve closed . . . . . . . . . . . . . . . . . 15
Burner start-up cycle diagnostics. . . . . . . . . . . . . . . . . . . . . . . 16
Resetting the control box and using diagnostics. . . . . . . . . . . 16
Fault - Probable cause - Suggested remedy . . . . . . . . . . . . . . . 18
Normal operation / flame detection time. . . . . . . . . . . . . . . . . . . 19
Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Appendix .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Switchboard layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
N.B.
Figures mentioned in the text are identified as follows:
1)(A) =part 1 of figure A, same page as text;
1)(A)p.8 =part 1 of figure A, page number 8.

2
TECHNICAL DATA
(1) Reference conditions: Ambient temperature 20°C - Gas temperature 15°C - Barometric pressure 1013 mbar - Altitude 0 m s.l.m.
(2) Pressure at test point 7)(A)p.3, with zero pressure in the combustion chambre, an maximum burner output.
(2) Sound pressure measured in manufacturer's combustion laboratory, with burner operating on test boiler and at maximum rated output. The sound power is mea-
sured with the “Free Field” method, as per EN 15036, and according to an “Accuracy: Category 3” measuring accuracy, as set out in EN ISO 3746.
VARIANTS
Blast tube lenght mm 250 - 385
ELECTRICAL DATA
Model RS 64 MZ
Type 885 T80
Output (1) Max. kW 400 - 850
345 - 730
Mcal/h
Min. kW 150
130
Mcal/h
Fuel Gas natural: G20 - G21 - G22 - G23 - G25
G20 G25
- Net calorific value kWh/Sm3
Mcal/Sm3
9.45
8.2
8.13
7.0
- Absolute density kg/Sm30.71 0.78
- Max. delivery Sm3/h 90 104.5
- Pressure at max. delivery (2) mbar 10.7 16.1
Operation • On-Off (1 stop min each 24 hours).
• Two-stage (high and low flame) and single-stage (all - nothing)
Standard applications Boilers: water, steam, diathermic oil
Ambient temperature °C 0 - 40
Combustion air temperature °C max 60
Noise levels (3) Sound pressure
Sound power dBA 76 87
Model RS 64 MZ
Type 885 T80
Electrical supply V
Hz
220 - 380 with neutral ~ +/-10%
60 - three-phase
Electric motor IE3 rpm
kW
V
A
3490
1,1
230/380
4.2 - 2.4
Ignition transformer V1 - V2
I1 - I2
230 V - 1x15 kV
1 A - 25 mA
Electrical power consumption kW max 1.5
Electrical protection (EN 60529) IP 40
GB

3
DESCRIPTION (A)
1 Combustion head
2 Ignition electrode
3 Screw for combustion head adjustment
4Sleeve
5 Minimum air pressure switch
(differential operating type)
6 Flame sensor probe
7 Air pressure test point
8 Gas pressure test point and head fixing
screw
9 Screw securing fan to sleeve
10 Slide bars for opening the burner and
inspecting the combustion head
11 Servomotor controlling the gas butterfly
valve and air gate valve (by means of a vari-
able profile cam mechanism).
When the burner is stopped the air gate valve
will be completely closed to reduce to a mini-
mum heat loss due to the flue draught: the lat-
ter tends to draw air from the fan suction inlet.
12 Plate with 4 hole knock-outs for electrical
cable routing
13 Air inlet to fan
14 Gas input pipework
15 Gas butterfly valve
16 Boiler mounting flange
17 Flame stability disk
18 Flame inspection window
19 Control box with lock-out pilot light and lock-
out reset button
20 Power switch for different operations:
automatic - manual - off
Button for:
power increase - power reduction.
21 Plugs for electrical connections
22 Air gate valve
23 Plug-socket on ionisation probe cable
24 Motor contact maker and thermal cutout with
reset button
25 Engine protection
Two types of burner failure may occur:
•CONTROL BOX LOCK-OUT: 
if the control box 19)(A) pushbutton lights up,
it indicates that the burner is in lock-out.
To reset, press the pushbutton.
• MOTOR LOCKOUT:
three-phase electrical supply; to unblock,
press the thermal cutout switch 24)(A).
PACKAGING - WEIGHT (B) - Approximate
measurements
• The burners are shipped in cardboard boxes
with the maximum dimensions shown in table
(B).
• The weight of the burner complete with pack-
aging is indicated in table (B).
MAX. DIMENSIONS (C) -Approximate mea-
surements
The maximum dimensions of the burner are
given in (C).
Note that if you need to examine the combustion
head, the burner must be pulled backward on
the slide bars and turned upward.
The maximum dimension of the burner, without
the cover, when open is give by measurement
H.
STANDARD EQUIPMENT
1 - Gas train flange
1 - Flange gasket
4 - Flange fixing screws M 10 x 35
1 - Thermal insulation screen
4 - Screws to secure the burner flange to the
boiler: M 12 x 35
5 - Fairleads for electrical connections
1-Engine protection (with fixing screws)
1-Plugs unit
1 - Instruction booklet
1 - Spare parts list
D7837
(B)
A
D
H
I
M
V
E
O
N
L F
B
mm ABCkg
RS 64 MZ 1200 520 580 42
(1) Blast tube: short-long
mm A B D E F (1) HILONVM
RS 64 MZ 533 300 490 640 250 - 385 179 352 222 870 134 221 2”
(C)
D88
D3906
D3900
(A)
D7628

A
(A)
(B)
200 mm MAX
RS 64 MZ
D497
D1079
(C)
D3903
A
(A)
(B)
200 mm MAX
RS 64 MZ
D497
D1079
(C)
D3903
pressure mbar
Combustion chamber
Combustion chamber
length m
4
FIRING RATE (A)
During operation, burner output varies between:
•aMAXIMUM OUTPUT, selected within area A,
•and a MINIMUM OUTPUT, which must not be
lower than the minimum limit in the diagram.
Important
the FIRING RATE area values have been
obtained considering a surrounding temperature
of 20 °C, and an atmospheric pressure of 1013
mbar (approx. 0 m above sea level) and with the
combustion head adjusted as shown on page 7.
TEST BOILER (B)
The firing rates were set in relation to special
test boilers, according to EN 676 regulations.
Figure (B) indicates the diameter and length of
the test combustion chamber.
Example
Output 350 Mcal/h:
diameter = 50 cm, length = 1.5 m.
COMMERCIAL BOILERS (C)
The burner/boiler combination does not pose
any problems if the boiler is CE approved and its
combustion chamber dimensions are similar to
those indicated in diagram (B).
If the burner must be combined with a commer-
cial boiler that has not been CE approved and/or
its combustion chamber dimensions are clearly
smaller than those indicated in diagram (B),
consult the manufacturer.
In addition, for inversion boilers you are advised
to check the length of the combustion head, as
indicated by the boiler manufacturer.
The maximum thickness of the boiler’s front door
must not exceed 200 mm (see fig. C).

(A)
2
VS VR
R
3
1
F
RS 64 MZ p (mbar)
kW 1 2
3
3970144
3970197
3970180
3970198
3970181
3970182
3970221
3970225
400 2.0 0.3 14.1 7.4 5.2 3.8
450 2.8 0.4 17.0 8.8 6.1 4.0
475 3.3 0.5 18.4 9.4 6.6 4.1
500 3.7 0.5 19.9 10.1 7.0 4.2
550 4.5 0.6 23.2 11.6 8.2 4.4
600 5.4 0.7 26.7 13.2 9.5 4.6
625 5.8 0.8 28.5 13.9 10.1 4.7
650 6.3 0.9 30.3 14.7 10.8 4.9
700 7.4 1.0 34.0 16.4 12.1 5.1
750 8.5 1.2 37.7 18.0 13.4 5.4
800 9.6 1.3 41.5 19.9 14.8 5.8
850 10.7 1.5 45.3 21.8 16.3 6.2
(B)
D3790
2 3 4 51
D3928
(C)
The data of thermal output and combustion head gas pressure are related
to full open (90°) gas butterfly valve.
5
GAS PRESSURE
The adjacent tables show minimum pressure
losses along the gas supply line depending on
the maximum burner output operation.
Column 1
Pressure loss at combustion head.
Gas pressure measured at test point 1)(B), with:
combustion chamber at 0 mbar.
Column 2
Pressure loss at gas butterfly valve 2)(B) with
maximum opening: 90°.
Column 3
Pressure loss of gas train 3)(B) includes: adjust-
ment valve VR, safety valve VS (both fully
open), pressure governor R, filter F.
The values shown in the various tables refer to:
natural gas G 20 PCI 9.45 kWh/Sm3 (8.2 Mcal/
Sm3)
With:
natural gas G 25 PCI 8.13 kWh/Sm3 (7.0 Mcal/
Sm3)
multiply tabulated values:
- column 1 - 2: by 1.5
- column 3:by 1.35
Calculate the approximate maximum output of
the burner thus:
- subtract the combustion chamber pressure
from the gas pressure measured at test point
1)(B).
- Find the nearest pressure value to your result
in column 1 of the table for the burner.
- Read off the corresponding output on the left.
Example:
• Maximum output operation
• Natural gas G 20 PCI 9.45 kWh/Sm3
• Gas pressure at test point 1)(B) =6.7 mbar
• Pressure in combustion chamber = 3 mbar
6.7 - 3 =3.7 mbar
A maximum output of 500 kW shown in Table
RS 64 MZ corresponds to 5 mbar pressure, col-
umn 1.
This value serves as a rough guide, the effective
delivery must be measured at the gas meter.
To ca lculate the required gas pressure at test
point 1)(B), set the maximim output required
from the burner operation:
- find the nearest output value in the table for
the burner in question.
- Read off the pressure at test point 1)(B) on
the right in column 1.
- Add this value to the estimated pressure in
the combustion chamber.
Example:
• Required burner maximum output operation:
500 kW
• Natural gas G 20 PCI 9.45 kWh/Sm3
• Gas pressure at burner output of 500 kW, taken
from table RS 64 MZ, column 1 = 3.7 mbar
• Pressure in combustion chamber = 3 mbar
3.7 + 3=6.7 mbar
pressure required at test point 1)(B).
INSTALLATION
!
THE BURNER MUST BE INSTALLED
IN CONFORMITY WITH LEGISLATION
AND LOCAL STANDARDS.
WORKING POSITION (C)
!
The burner is designed to work only in
the positions 1, 2, 3 and 4. 
Installation 1is preferable, as it is the on-
ly one that allows the maintenance operations
as described in this manual. Installations 2, 3
and 4 allow the working, but make the opera-
tions of maintenance and checking of the com-
bustion head more difficult page 14.
Any other position could compromise the
correct working of the appliance. 
Installation 5is forbidden, for safety rea-
sons.

4
3
1
2
mm A B C
RS 64 MZ 185 275 - 325 M 12
(B)
(D)
(C)
D455
D613
D3904
(E)
(A)
D3984
PROBE ELECTRODE
D7648
!
6
BEFORE ASSEMBLING THE CASING,
IT IS NECESSARY TO FIX THE
ENGINE PROTECTION SUPPLIED
(1)(A) ONTO THE BRACKET (2)(A), USING
THE APPROPRIATE SCREWS (3)(A) WITH A
NUT AND A WASHER. FIX THE BRACKET TO
THE FRONT SHIELD OF THE BURNER,
USING THE SCREWS (4)(A).
BOILER PLATE (B)
Drill the combustion chamber locking plate as
shown in (B). The position of the threaded holes
can be marked using the thermal screen sup-
plied with the burner.
BLAST TUBE LENGTH (C)
The length of the blast tube must be greater
than the thickness of the boiler door complete
with its fettling. The lengths, L (mm), are:
Blast tube 10):
• short 250
• long 385
For boilers with front flue passes 15) or flame
inversion chambers, protective fettling in refrac-
tory material 11), must be inserted between the
boiler fettling 12) and the blast tube 10).
This protective fettling must not compromise the
extraction of the blast tube.
For boilers having a water-cooled front the refrac-
tory fettling 11)-12) is not required unless it is
expressly requested by the boiler manufacturer.
SECURING THE BURNER TO THE
BOILER (D)
Before securing the burner to the boiler, check
through the blast tube opening to make sure
that the flame sensor probe and the ignition
electrode are correctly set in position, as shown
in (D).
Now detach the combustion head from the
burner, fig. (C):
- Remove screw 13) and withdraw the cover
14).
-Disengage the articulated coupling 4) from the
graduated sector 5).
- Remove the screws 2) from the slide bars 3).
- Remove screw 1) and pull the burner back on
slide bars 3) by about 100 mm.
- Disconnect the wires from the probe and the
electrode and then pull the burner completely
off the slide bars, after removing the split pin
from the slide bar 3).
Secure the flange 9)(C) to the boiler plate, inter-
posing the thermal insulating screen 6)(C) sup-
plied with the burner. Use the 4 screws, also
supplied with the unit, after first protecting the
thread with an anti-locking product.
The seal between burner and boiler must be air-
tight.
If you noticed any irregularities in the positions
of the probe or ignition electrode during the
check mentioned above, remove screw 1)(E),
extract the internal part 2)(E) of the head and
proceed to set up the two components correctly.
Do not attempt to turn the probe. Leave it in the
position shown in (D) since if it is located too
close to the ignition electrode the control box
amplifier may be damaged.

(B)
(C)
Notches (Air=Gas)
Max burner output
D3905
D3909
D3985
(A)
7
COMBUSTION HEAD SETTING
Installation operations are now at the stage
where the blast tube and sleeve are secured to
the boiler as shown in fig. (A). It is now a very
simple matter to set up the combustion head, as
this depends solely on the MAX output devel-
oped by the burner.
It is therefore essential to establish this value
before proceeding to set up the combustion
head.
Adjustment of the head on the air side is
required.
In diagram (B) find the notch to use for adjusting
the air and the gas, and then proceed as fol-
lows:
Air adjustment (A)
Turn screw 4)(A) until the notch identified is
aligned with the front surface 5)(A) of the flange.
Example
MAX output = 500 Mcal/h.
If we consult diagram (B) we find that for this
output, air must be adjusted using notch 7.5, as
shown in fig. (A).
Once you have finished setting up the head, refit
the burner to the slide bars 3)(C) at approxi-
mately 100 mm from the sleeve 4)(C) - burner
positioned as shown in fig. (C)p.6 - insert the
flame detection probe cable and the ignition
electrode cable and then slide the burner up to
the sleeve so that it is positioned as shown in
fig. (C).
Refit screws 2) on slide bars 3).
Secure the burner to the sleeve by tightening
screw 1).
Reconnect the articulation 6) to the graduated
sector 5).
Important
When fitting the burner on the two slide bars, it
is advisable to gently draw out the high tension
cable and flame detection probe cable until they
are slightly stretched.

(B)
(C)
(A) D505
D3791
L1 L
P2
P1
123
4
5
67
8
9
10
11
BURNERS AND RELEVANT GAS TRAINS APPROVED ACCORDING TO EN 676
GAS TRAINS L 7 11
Code Model Ø C.T. Code Code
3970144 MB-DLE 412 1”1/4” - 3010123 3000843
3970197 MB-DLE 412 CT 1”1/4” 3010123 3000843
3970180 MB-DLE 415 1”1/2 - 3010123 3000843
3970198 MB-DLE 415 CT 1”1/2 3010123 3000843
3970181 MB-DLE 420 2” - 3010123 -
3970182 MB-DLE 420 CT 2” --
3970221 MBC-1200-SE-50 2” - 3010123 -
3970225 MBC-1200-SE-50 CT 2” --
8
GAS LINE
• The gas train must be connected to the gas
attachment 1)(A), using flange 2), gasket 3)
and screws 4) supplied with the burner.
• The gas train can enter the burner from the
right or left side, depending on which is the
most convenient, see fig. (A).
• Gas solenoids must be as close as possible to
the burner to ensure gas reaches the combus-
tion head within the safety time range of 3s.
• Make sure that the pressure governor calibra-
tion range (colour of the spring) comprises the
pressure required by the burner.
GAS TRAIN (B)
It is type-approved according to EN 676 Stan-
dards and is supplied separately from the burner
with the code indicated in table (C).
KEY (B)
1 - Gas input pipe
2 - Manual valve
3 - Vibration damping joint
4 - Pressure gauge with pushbutton cock
5 - Multibloc, including:
- filter (replaceable)
- working valve
- pressure adjuster
6 - Minimum gas pressure switch
7 - Valve seal checking device.
In accordance with the standard EN 676,
gas valve leak detection control devices
are compulsory for burners with maximum
outputs of more than 1200 kW.
8-Gasket
9 - Gas adjustment butterfly valve
10 - Max gas pressure switch (accessory)
11 - Gas train/burner adaptor
P1 - Pressure at combustion head
P2 - Up-line pressure of valves/adjuster
L - Gas train supplied separately with the code
indicated in table (C)
L1 - The responsibility of the installer
KEY TO TABLE (C)
C.T.= Gas valves leak detection control
devices:
- = Gas train without gas valve leak
detection control device; device that
can be ordered separately and
assembled subsequently (see Col-
umn 7).
=Gas train with assembled VPS valve
leak detection control device.
7 = VPS valve leak detection control device.
Supplied separately from gas train on
request.
11 = Gas train/burner adaptor.
Supplied separately from gas train on
request.
Note
See the accompanying instructions for the
adjustment of the gas train.

(A)
(C)
MIN GAS PRESSURE SWITCH AIR PRESSURE SWITCH
SERVOMOTOR
(D)
12
Burner off
Burner on
1st stage
2nd stage
(E)
(B)
D897
D517
D469
+-
D7838
9
ADJUSTMENTS PRIOR TO IGNITION
!
WARNING
THE FIRST IGNITION MUST BE CARRIED
OUT BY QUALIFIED PERSONNEL WITH THE
RIGHT INSTRUMENTS.
Adjustment of the combustion head, and air and
gas deliveries has been illustrated on page 7.
In addition, the following adjustments must also
be made:
- open manual valves up-line from the gas
train.
- Adjust the minimum gas pressure switch to
the start of the scale (A).
- Adjust the air pressure switch to the zero
position of the scale (B).
- Purge the air from the gas line.
Continue to purge the air (we recommend
using a plastic tube routed outside the build-
ing) until gas is smelt.
- Fit a manometer (C) to the gas pressure test
point on the sleeve.
The manometer readings are used to calcu-
late the 2nd stage operation burner power
using the tables on page 5.
- Connect two lamps or testers to the two gas
line solenoid valves VR and VS to check the
exact moment at which voltage is supplied.
This operation is unnecessary if each of the
two solenoid valves is equipped with a pilot
light that signals voltage passing through.
Before starting up the burner it is good practice
to adjust the gas train so that ignition takes
place in conditions of maximum safety, i.e. with
gas delivery at the minimum.
SERVOMOTOR (D)
The servomotor provides simultaneous adjust-
ment of the air gate valve, by means of the vari-
able profile cam, and the gas butterfly valve.
The angle of rotation of the servomotor is equal
to the angle on the graduated sector controlling
the gas butterfly valve. The servomotor rotates
through 90 degrees in 12 seconds.
Do not alter the factory setting for the 4 cams;
simply check that they are set as indicated
below:
Cam St2 : 90°
Limits rotation toward maximum position. When
the burner is in 2nd stage operation the gas but-
terfly valve must be fully open: 90°.
Cam St0 : 0°
Limits rotation toward the minimum position.
When the burner is shut down the air gate valve
and the gas butterfly valve must be closed: 0°.
Cam St1 : 15°
Adjusts the ignition position and the output in 1st
stage operation.
Cam MV : not used
BURNER STARTING
Close the control devices and set:
• switch 1)(E) to "Burner ON" position
• switch 2)(E) to "1st STAGE" position.
As soon as the burner starts check the direction
of rotation of the fan blade, looking through the
flame inspection window 18)(A)p.3.
Make sure that the lamps or testers connected
to the solenoids, or pilot lights on the solenoids
themselves, indicate that no voltage is present.
If voltage is present, then immediately stop the
burner and check electrical connections.
BURNER FIRING
Having completed the checks indicated in the
previous heading, the burner should fire. If the
motor starts but the flame does not appear and
the control box goes into lock-out, reset and wait
for a new firing attempt.
If firing is still not achieved, it may be that gas is
not reaching the combustion head within the
safety time period of 3 seconds.
In this case increase gas firing delivery.
The arrival of gas at the sleeve is indicated by
the manometer (C). Once the burner has fired,
now proceed with global calibration operations.

(A)
12
Burner off
Burner on
1st stage
2nd stage
D469
10
BURNER CALIBRATION
The optimum calibration of the burner requires
an analysis of the flue gases at the boiler outlet.
Adjust successively:
1 - firing output
2 - 2nd stage burner output
3 - 1st stage burner output
4 - Intermediate outputs between 1st and 2nd
stage
5 - Air pressure switch
6 - Minimum gas pressure switch
1 - FIRING OUTPUT
According to EN 676 Regulations:
Burners with max. output up to 120 kW
Firing can be performed at the maximum opera-
tion output level. Example:
• Max. operation output : 120 kW
• Max. firing output : 120 kW
Burners with max. output above 120 kW
Firing must be performed at a lower output than
the max. operation output. If the firing output
does not exceed 120 kW, no calculations are
required. If firing output exceeds 120 kW, the
regulations prescribe that the value be defined
according to the control box safety time "ts":
• for "ts" = 2s, firing output must be equal to or
lower than 1/2 of max. operation output.
• For "ts" = 3s, firing output must be equal to or
lower than 1/3 of max. operation output.
Example
MAX operation output of 600 kW.
Firing output must be equal to or lower than:
• 300 kW with ts = 2s
• 200 kW with ts = 3s
In order to measure the firing output:
- disconnect the plug-socket 23)(A)p.3on the
ionization probe cable (the burner will fire and
then go into lock-out after the safety time has
elapsed).
- Perform 10 firings with consecutive lock-outs.
- On the meter read the quantity of gas burned.
This quantity must be equal to or lower than
the quantity given by the formula, for ts = 3s:
Vg = Qa (max. burner output) x n x ts
3600
Vg: volume supplied upon ignitions carried out
(Sm3)
Qa: ignition output (Sm3/h)
n: number of ignitions (10)
ts: safety time (sec)
Example: for gas G 20 (9.45 kWh/Sm3):
ignition output 400 kW
corresponding to 47.6 Sm3/h.
After 10 firings with lock-outs, the delivery read
on the meter must be equal to or lower than::
Vg = 47.6 x 10 x 3 = 0.397 Sm3
3600
2 - 2ND STAGE OUTPUT
2nd stage output of the burner must be set
within the firing rate range shown on page 4.
In the above instructions we left the burner run-
ning in 1st stage operation. Now set switch 2)(A)
to the 2nd stage position: the servomotor will
open, simultaneously, the air gate valve and the
gas butterfly valve to 90°.
Gas calibration
Measure the gas delivery at the meter.
A guideline indication can be calculated from the
tables on page 5, simply read off the gas pres-
sure on manometer, see fig.(C) on page 9, and
follow the instructions on page 5.
- If delivery needs to be reduced, diminish out-
let gas pressure and, if it is already very low,
slightly close adjustment valve VR.
- If delivery needs to be increased, increase
outlet gas pressure.

(B)
(A)
1Servomotor
2 Cam 4 engaged /disengages
3Camcover
4 Adjustable profile cam
5 Cam profile adjustment screws
6 Opening for access to screws 5
7 Index for graduated sector 8
8 Graduated sector for gas butterfly valve
D518
D520
11
Adjusting air delivery
Progressively adjust the end profile of cam 4)(A)
by turning the cam adjustment screws as they
appear through the access opening 6)(A).
- Turn the screws clockwise to increase air
delivery.
- Turn the screws counter-clockwise to reduce
air delivery.
3 - 1ST STAGE OUTPUT
Burner power in 1st stage operation must be
selected within the firing rate range shown on
page 4.
Set the switch 2)(A)p.10 to the 1st stage posi-
tion: the servomotor 1)(A) will close the air gate
valve and, at the same time, closes the gas but-
terfly valve down to 15°, i.e. down to the original
factory setting.
Adjusting gas delivery
Measure the delivery of gas from the gas meter.
- If this value is to be reduced, decrease the
angle of cam St1 (B) slightly by proceeding a
little at a time until the angle is changed from
15° to 13° or 11°....
- If it is necessary to increase the mains pres-
sure, move to 2nd stage operation by altering
the setting of switch 2)(A)p.10 and increase
the angle of cam St1, proceeding a little at a
time until the angle is changed from 15° to
17° - 19°....
At this point return to 1st stage operation and
measure gas delivery.
Note
The servomotor follows the adjustment of cam
St1 only when the angle is reduced. If, however
the angle must be increased, switch to 2nd
stage operation, increase the angle and then
return to 1st stage operation to check the effect
of the adjustment.
If you increase the angle of St1 while the burner
is operating in 1st stage, lock-out will result.
In order to adjust cam St1, remove press-fit
cover 1), as shown in fig.(B), extract the relevant
key 2) from inside, and fit it into the keyway in
cam St1.
Adjustment of air delivery
Progressively adjust the starting profile of cam
4)(A) by turning the screws working throught the
access hole 6)(A). It is preferable not to turn the
first screw since this is used to set the air gate
valve to its fully-closed position.
4 - INTERMEDIATE OUTPUTS
Adjustment of gas delivery
No adjustment of gas delivery is required.
Adjustment of air delivery
Switch off the burner using switch 1)(A)p.10,
disengage the variable profile cam, set the ser-
vomotor shaft slot 2)(A) to a vertical position and
turn the central screws of the cam so that the
cam offers a progressive gradient. Try turning
the cam back and forth by hand a few times until
the movement is completely smooth with no
signs of sticking.
Do not alter the position of the screws at each
end of the cam track, which have already been
adjusted for 1st and 2nd stage air gate valve
control.
Note
Once you have finished adjusting 2nd stage -
1st stage - intermediate outputs, check ignition
once again: noise emission at this stage must
be identical to the following stage of operation. If
you notice any sign of pulsations, reduce the
ignition stage delivery.

(A)
AIR PRESSURE SWITCH 5)(A)p.3
MIN GAS PRESSURE SWITCH 6)(B)p.8
(B)
(C)
D521
D896
D3023
12
5 - AIR PRESSURE SWITCH (A)
Adjust the air pressure switch after having per-
formed all other burner adjustments with the air
pressure switch set to the start of the scale (A).
With the burner operating in 1st stage, increase
adjustment pressure by slowly turning the rela-
tive knob clockwise until the burner locks out.
Then turn the knob anti-clockwise by about 20%
of the set point and repeat burner starting to
ensure it is correct.
If the burner locks out again, turn the knob anti-
clockwise a little bit more.
Attention
As a rule, the air pressure switch must limit the
CO in the fumes to less than 1% (10,000 ppm).
To check this, insert a combustion analyser into
the chimney, slowly close the fan suction inlet
(for example with cardboard) and check that the
burner locks out, before the CO in the fumes
exceeds 1%.
The air pressure switch may operate in "differ-
ential" operation in two pipe system. If a nega-
tive pressure in the combustion chamber during
pre-purging prevents the air pressure switch
from switching, switching may be obtained by fit-
ting a second pipe between the air pressure
switch and the suction inlet of the fan. In such a
manner the air pressure switch operates as dif-
ferenzial pressure switch.
Warning
The use of the air pressure switch with differen-
tial operation is allowed only in industrial appli-
cations and where rules enable the air pressure
switch to control only fan operation without any
reference to CO limit.
6 - MINIMUM GAS PRESSURE SWITCH (B)
Adjust the minimum gas pressure switch (C) af-
ter having adjusted the burner, the gas valves
and the gas train stabiliser. With the burner oper-
ating at maximum output:
– install a pressure gauge downstream of the
gas train stabiliser (for example at the gas
pressure test point on the burner combus-
tion head);
– choke slowly the manual gas cock until the
pressure gauge detects a decrease in the
pressure read of about 0.1 kPa (1 mbar). In
this phase, verify the CO value which must
always be less than 100 mg/kWh (93 ppm).
– Increase the adjustment of the gas pressure
switch until it intervenes, causing the burner
shutdown;
– remove the pressure gauge and close the
cock of the gas pressure test point used for
the measurement;
– open completely the manual gas cock.
!
1 kPa = 10 mbar
FLAME PRESENT CHECK (C)
The burner is fitted with an ionisation system
which ensures that a flame is present. The mini-
mum current for plant operation is 5 µA.
The burner provides a much higher current, so
that controls are not normally required. How-
ever, if it is necessary to measure the ionisation
current, disconnect the plug-socket 23)(A)p.3 on
the ionisation probe cable and insert a direct
current microamperometer with a base scale of
100 µA.
Carefully check polarities!

(A)
(B)
NORMAL FIRING
(n° = seconds from instant 0)
NO FIRING
D3028
D3029
RMG
LED *
Off Yellow Green Red
For further details see page 16.
*
Off Yellow Red
For further details see page 16.
*
RMG
LED *
13
BURNER OPERATION
BURNER STARTING (A)
• : Control device TL closes.
Servomotor starts: it rotates during
opening up to the angle set on cam
St1.
After about 3s:
• 0 s : The control box starting cycle begins.
• 2 s : Fan motor starts.
• 3 s : Servomotor starts: it rotates during
opening until contact on cam St2 is
tripped.
The air gate valve is positioned to 2nd
stage output.
Pre-purge stage with air delivery at
2nd stage output.
Duration 25 seconds.
• 28 s : Servomotor starts: it rotates during
closing up to the angle set on cam
St1.
• 43 s : The air gate valve and the gas butter-
fly are positioned to 1st stage output.
Ignition electrode strikes a spark.
Safety valve VS and adjustment valve
VR (rapid opening) open. The flame
is ignited at a low output level, point
A. Output is then progressively
increased, with the valve opening
slowly up to 1st stage output, point B.
• 45 s : The spark goes out.
• 53 s : If remote control device TR is closed
or if it has been replaced by a jumper,
the servomotor will continue to turn
until the cam St2 come into operation,
setting the air gate valve and the gas
butterfly valve to the 2nd stage opera-
tion position, section C-D.
The control box starting cycle ends.
STEADY STATE OPERATION (A)
System equipped with one control device TR.
Once the starting cycle has come to an end,
control of the servomotor passes on to the con-
trol device TR that controls boiler temperature or
pressure, point D.
(The control box will continue, however, to mon-
itor flame presence and the correct position of
the air pressure switch).
• When the temperature or the pressure
increases until the control device TR opens,
the servomotor closes the gas butterfly valve
and the air gate valve and the burner passes
from the 2nd to the 1st stage of operation,
section E-F.
• When the temperature or pressure decreases
until the control device TR closes, the servo-
motor opens the gas butterfly valve and the
air gate valve and the burner passes from the
1st to the 2nd stage of operation, and so on.
• The burner stops when the demand for heat
is less than the amount of heat delivered by
the burner in the 1st stage, section G-H. Con-
trol device TL now opens, the servomotor
returns toward the 0° position, limited in this
movement by cam St0. The air gate valve
closes completely to reduce heat losses to a
minimum.
Systems not equipped with control device TR
(jumper wire installed)
The burner is fired as described in the case
above. If the temperature or pressure increase
until control device TL opens, the burner shuts
down (Section A-A in the diagram).
FIRING FAILURE (B)
If the burner does not fire, it goes into lock-out
within 3s of the opening of the gas solenoid
valve and 49s after the closing of control
device TL. The control box red pilot light will
light up.
BURNER FLAME GOES OUT DURING OPER-
ATION
If the flame should accidentally go out during
operation, the burner will lock out within 1s.

(A)
FLAME INSPECTION WINDOW
D484
14
FINAL CHECKS (with burner running)
• Disconnect one of the wires on the minimum
gas pressure switch.
• Open remote control device TL.
• Open remote control device TS:
the burner must stop.
• Detach the air feed pipe to the pressure
switch.
• Disconnect the ionisation probe lead:
the burner must lock out.
• Make sure that the mechanical locking sys-
tems on the various adjustment devices are
fully tightened.
!
MAINTENANCE
The burner requires periodic maintenance
carried out by a qualified and authorised
technician in conformity with legislation and
local standards.
!
Periodic maintenance is essential for the
reliability of the burner, avoiding the
excessive consumption of fuel and consequent
pollution.
!
Before carrying out any cleaning or
control, always switch off the electrical
supply to the burner, using the main switch of
the system.
Combustion
The optimum calibration of the burner requires
an analysis of the flue gases. Significant differ-
ences with respect to the previous measure-
ments indicate the points where more care
should be exercised during maintenance.
Gas leaks
Make sure that there are no gas leaks on the
pipework between the gas meter and the burner.
Gas filter
Change the gas filter when it is dirty.
Flame inspection window
Clean the flame inspection window (A).
Combustion head
Open the burner and make sure that all compo-
nents of the combustion head are in good condi-
tion, not deformed by the high temperatures,
free of impurities from the surroundings and cor-
rectly positioned. If in doubt, disassemble the
elbow fitting.
Servomotor
Disengage the cam 4)(A)p.11 from servomotor,
by turning slot 2)(A)p.11 through 90° and turn it
backward and forward by hand to make sure it is
free moving. Now engage cam 4)(A)p.11 again.
Burner
Check for excess wear or loose screws in the
mechanisms controlling the air gate valve and
the gas butterfly valve. Also make sure that the
screws securing the electrical leads in the
burner terminal strip are fully tightened.
Clean the outside of the burner, taking special
care with the transmission joints and cam
4)(A)p.11.
Combustion
Adjust the burner if the combustion values found
at the beginning of the operation do not comply
with the regulations in force, or at any rate, do
not correspond to good combustion. Use the
appropriate card to record the new combustion
values; they will be useful for subsequent con-
trols.

(A)
OPENING THE BURNER
D535
15
TO OPEN THE BURNER (A):
- switch off the electrical power.
- Remove screw 1) and withdraw cover 2).
-Disengage the articulated coupling 3) from
the graduated sector 4).
- Remove screw 5), the split pin 9) and pull the
burner back by about 100 mm on the slide
bars 6). Disconnect the probe and electrode
leads and then pull the burner fully back.
- Turn the burner as shown in the figure and fit
the split pin 9) into one of the slide bar holes
so that the burner remains in position.
Now extract the gas distributor 7) after having
removed the screw 8).
TO CLOSE THE BURNER (A):
- remove the split pin 9) push the burner until it
is about 100 mm from the sleeve.
- Re-connect the leads and slide in the burner
until it comes to a stop.
- Refit screw 5), the split pin 9) and pull the
probe and electrode leads gently out until
they are slightly stretched.
- Re-couple the articulated coupling 3) to the
graduated sector 4).

16
SAFETY TEST - WITH GAS BALL VALVE
CLOSED
It is fundamental to ensure the correct execution
of the electrical connections between the gas so-
lenoid valves and the burner to perform safely
the commissioning.
For this purpose, after checking that the connec-
tions have been carried out in accordance with
the burner's electrical diagrams, an ignition cycle
with closed gas ball valve -dry test- must be per-
formed.
1 The manual ball gas valve must be closed
2 The electrical contacts of the burner limit
switch need to be closed
3 Ensures closed the contact of the low gas
pressure switch
4 Make a trial for burner ignition
The start-up cycle must be as follows:
– starting the fan for pre-ventilation
– Performing the gas valve seal control, if pro-
vided
– Completion of pre-ventilation
– Arrival of the ignition point
– Power supply of the ignition transformer
– Electrical Supply of solenoid gas valves
Since the manual gas ball valve is closed, the
burner will not light up and its control box will go
to a safety lockout condition.
The actual electrical supply of the solenoid gas
valves can be verified by inserting a tester,
Some valves are equipped with light signals (or
close/open position indicator) that turn on at the
same time as their power supply.
SAFETY COMPONENTS
The safety components must be replaced at the
end of their life cycle indicated in Tab, (A). The
specified life cycles do not refer to the warranty
terms indicated in the delivery or payment con-
ditions.
IF THE ELECTRICAL SUPPLY OF THE
GAS VALVES OCCURS AT
UNEXPECTED TIMES. DO NOT OPEN
MANUAL GAS BALL VALVE, SWITCH
OFF POWER LINE; CHECK THE
WIRES; CORRECT THE ERRORS AND
REPEAT THE COMPLETE TEST.
Safety component Life cycle
Flame control 10 years or 250,000
operation cycles
Flame sensor 10 years or 250,000
operation cycles
Gas valves (solenoid) 10 years or 250,000
operation cycles
Pressure switches 10 years or 250,000
operation cycles
Pressure adjuster 15 years
Servomotor (electronic cam) (if present) 10 years or 250,000
operation cycles
Oil valve (solenoid)
(if present)
10 years or 250,000
operation cycles
Oil regulator (if present) 10 years or 250,000
operation cycles
Oil pipes / couplings (metallic) (if present) 10 years
Fan impeller 10 years or 500,000 start-ups
(A)