Riello RS 160/M LN Quick start guide

2915849 (8) - 06/2014
Installation, use and maintenance instructions
Gas burners
Low-High-Low or Modulating Operation
CODE MODEL
20011691 RS 160/M LN
3788070 RS 160/M LN
3788075 RS 160/M LN
GB

1
CONTENTS
TECHNICAL DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2
Electrical data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Burner models designations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Burner description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Packaging - Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Max. dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Standard equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Firing rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Minimum furnace dimensions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Commercial boilers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Gas pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Boiler mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Blast tube length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Securing the burner to the boiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Ignition pilot adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Combustion head adjustment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Gas piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Electrical wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Motor connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Adjustments before first firing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Servomotor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Burner starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Maximum output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Minimum output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Intermediates outputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Air pressure switch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
High gas pressure switch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Low gas pressure switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Flame present check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
MAINTENANCE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Burner operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Burner faults. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Procedure to refer burner operating condition in high
altitude plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
APPENDIX
Spare parts list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Burner start up report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
WARNING
If you smell gas:
• Do not touch any electrical items.
• Open all windows.
• Close all gas supply valves.
• Contact your local gas authority immediately.
Do not store flammable or hazardous materials in the vicinity of
fuel burning appliances.
Improper installation, adjustment, alteration, service or mainte-
nance can cause property damage, personal injury or death. Re-
fer to this manual for instructional or additional information.
Consult a certified installer, service representative or the gas
supplier for further assistance.
Burner shall be installed in accordance with manufacturers re-
quirementsasoutlined inthismanual,localcodesand authorities
having jurisdiction.

2
TECHNICAL DATA
(1) Reference conditions: Ambient temperature 68 °F (20 °C) - Barometric pressure 394” WC - Altitude 329 ft.
(2) Pressure at test point 17)(A)p.4, with zero pressure in the combustion chamber, with open gas ring 2)(B)p.6 at maximum burner output
(3) Sound pressure measured in manufacturer’s combustion laboratory, with burner operating on test boiler and at maximum rated output.
* Firing rate for C-UL Canadian Listing (CNL)
ELECTRICAL DATA
Model RS 160/M LN
Output
(1)
MAX. kW
MBtu/hr 1032 - 2065 (1847 *) 3521 - 7046 (6302 *)
MIN. kW
MBtu/hr 333 1136
Fuel Natural gas
- max. delivery SCFH 7046
- pressure at max. delivery
(2)
“WC 7
Operation Low - high or modulating
Standard applications Boilers: water, steam, thermal oil
Ambient temperature °F 32 - 104 (0 - 40 °C)
Combustion air temperature °F max 140 (60 °C)
Noise levels
(3)
dB(A) 83.1
Model RS 160/M LN
Control circuit power supply
Main power supply (+/-10%) V/Ph/Hz V/Ph/Hz 120/1/60 208-220/3/60 120/1/60 460/3/60 120/1/60 575/3/60
Fan motor IE2
rpm
kW - HP
V
A
3430
4.0 - 5.5
208-230
13.2
3430
4.0 - 5.5
460
6.6
3540
4.0 - 5.5
575
5.3
Ignition transformer V1 - V2
I1 - I2 120 V - 1 x 8 kV 1.6 A - 20 mA
Electrical power consumption W 4550 4550 4600
Electrical control circuit cons. W max 750 750 750
Total electrical consumption W 5300 5300 5350
Electrical protection NEMA 1

3
BURNER MODELS DESIGNATIONS
ACCESSORIES (optional):
• TUBES KIT (see page 5): cod. 3010249
• THERMAL OVERLOAD
3013980: Thermal overload for 460 V power supply.
• GAS TRAIN ACCORDING TO UL STANDARDS: see page 9.
Model RBNA Code Riello Code Voltage Flame safeguard
RS 160/M LN tbd 20011691 208-230/3/60 Burner mounted
RS 160/M LN C9544000 3788070 460/3/60 Burner mounted
RS 160/M LN C9544001 3788075 575/3/60 Burner mounted
Important:
The installer is responsible for the supply and installation of any safety device(s) not indicated in this manual.

4
BURNER DESCRIPTION (A)
1 Combustion head
2 Ignition electrode
3 Screw for combustion head adjustment
4 High gas pressure switch
5 Sleeve
6 Servomotor controlling the gas butterfly valve and
the air damper (by means of a variable profile cam
mechanism).
When the burner is stopped the air damper will be
completely closed to reduce heat loss.
7 Plug-socket on flame rod cable
8 Extensions for slide bars 16) (supplied by kit)
9 Motor contactor and thermal overload with reset but-
ton
10 Power switch for different operations:
automatic - manual - off
Button for:
Power increase - power reduction
11 Terminal strip for electrical connection
12 Pilot burner attachment
13 Flame safeguard with lock-out pilot light and lock-out
reset button
14 Flame inspection window
15 Low air pressure switch
(differential operating type)
16 Slide bars for opening the burner and inspecting the
combustion head
17 Gas pressure test point and head fixing screw
18 Air pressure test point
19 Flame sensor probe (flame rod)
20 Air damper
21 Air inlet to fan
22 Screws securing fan to sleeve
23 Gas input pipework
24 Gas butterfly valve
25 Boiler mounting flange
26 Flame stability disk
27 Pilot burner
Two types of burner failure may occur:
• FLAME SAFEGUARD LOCK-OUT:
if the flame relay 13)(A) pushbutton lights up, it indi-
cates that the burner is in lock-out.
To reset, press the pushbutton.
• MOTOR TRIP:
release by pressing the pushbutton on thermal over-
load 9)(A).
PACKAGING - WEIGHT (B) - Approximate measure-
ments
• The burners are shipped skid mounted.
Outer dimensions of packaging are indicated in (B).
• The weight of the burner complete with packaging is
indicated in Table (B).
MAX. DIMENSIONS (C) -Approximate measurements
The maximum dimensions of the burners are given in
(C).
Bear in mind that inspection of the combustion head
requires the burner to be opened by withdrawing the
rear part on the slide bars.
The maximum dimension of the burner, when open is
give by measurement I.
STANDARD EQUIPMENT
1 - Gas train flange
1 - Flange gasket
4 - Flange fixing screws
1 - Burner head gasket
4 - Screws to secure the burner flange to the boiler:
1/2
W x 1
3/8
”
1 - Cap for combustion head
1 - Disc for combustion head
1 - Instruction booklet
1 - Spare parts list
(A)
A B C lbs
52
3/4
“ 28
1/2
“ 30
29/32
“198
D36
(B)
A B C D E F (1) G H I (1) L M N O
26
13/16
“ 14
13/32
“ 12
13/32
“ 21
27/32
“ 33
31/32
“ 14
11/16
“ - 19
13/16
“ 8
11/16
” 16
15/16
” 56
49/64
” - 62
31/64
” 9
21/64
” 5
29/32
” 7
5/16
”
2 ”
(C)
D2791
D1702
(1) Blast tube: short - long (with kit)

5
FIRING RATE (A)
During operation, burner output varies between:
• MAXIMUM OUTPUT, selected within area A,
•and MINIMUM OUTPUT, which must not be lower
than the minimum limit in the diagram.
RS 160 /M LN = 1136 MBtu/hr = 333 kW
Important
The FIRING RATE area values have been obtained con-
sidering an ambient temperature of 68 °F (20 °C), and
an atmospheric pressure of 394 “WC and with the com-
bustion head adjusted as shown on page 8.
Note:
The FIRING RATE areas given in figure (A) have been
reduced by 10% with respect to the maximum range that
can be reached.
Consult Procedure on page 15 to refer burner operating
condition in high altitude plants.
MINIMUM FURNACE DIMENSIONS (B)
The firing rates were set in relation to certified test boil-
ers.
Figure (B) indicates the diameter and length of the test
combustion chamber.
Example:
Output 2579 MBtu/hr:
diameter = 23.6 inch; length 6.6 ft
COMMERCIAL BOILERS (C) - IMPORTANT
The RS 160/M LN burner is suitable for operation on ei-
ther flame-inversion boilers*or boilers with combustion
chambers featuring flow from the base (three flue pass-
es) on which the best results are obtained in terms of low
NOx emissions.
The maximum thickness of the boiler’s front door must
not exceed 10” (see fig. C).
(*) For flame inversion boilers, a kit is available to reduce
CO emissions if required.
The kit includes 5 gas pipes, identical to the other 5
already fitted to the burner head. In standard condi-
tions, the burner head is fitted with a second group of
pipes, with gas outlet in a different direction with re-
spect to the others. With this Kit, the second group of
pipes is replaced, so that all the pipes are the same.
After fitting the kit, ensure they work correctly by
measuring the CO and flue gases emissions.
(A)
D2798
Combustion chamber pressure
“WC
(B)
D2919
10” max
D1079
(C)
Diameter (inches)
Length (feet)
Recommended furnace dimensions
Firing rate for C-UL Canadian Listing (CNL)
6302 MBtu/hr

6
GAS PRESSURE
The adjacent diagram shows minimum pressure losses
along the gas supply line depending on the maximum
burner output operation with natural gas.
Column 1
Gas manifold pressure measured at test point 1)(B),
with:
• Combustion chamber at 0” WC;
• Burner operating at maximum output;
• Combustion head adjusted as indicated in diagram
(C)p. 8.
Calculate the approximate maximum output of the
burner as follows:
- subtract the combustion chamber pressure from the
gas pressure measured at test point 1)(B).
- Find the nearest pressure value to your result in
diaram (A).
- Read off the corresponding output on the left.
Example
• Maximum output operation
• Natural gas
• Gas pressure at test point 1)(B) = 4.09“ WC
• Pressure in combustion chamber = 1.18“ WC
4.09 - 1.18 = 2.91“ WC
A maximum output of 4094 MBtu/hr shown in diagram
(A) corresponds to 2.91” WC pressure.
This value serves as a rough guide, the effective deliv-
ery must be measured at the gas meter.
(A)
D2441
(B)
1
2
D3188
∆p
[
“WC
]

7
INSTALLATION
BOILER PLATE (A)
Drill the combustion chamber mounting plate as shown
in (A). The position of the threaded holes can be marked
using the burner head gasket supplied with the burner.
BLAST TUBE LENGTH (B)
The length of the blast tube must be selected according
to the indications provided by the manufacturer of the
boiler, it must be greater than the thickness of the boiler
door complete with its insulation. The length available, L
(inches), is 14
11/16
“.
For boilers with front flue passes 15) or flame inversion
chambers, protective insulation material 13), must be
inserted between the boiler refractory 14) and the blast
tube 12).
This protective insulation must not compromise the
extraction of the blast tube.
For boilers having a water-cooled front, the insulation
13)-14) is not required unless it is required by the boiler
manufacturer.
SECURING THE BURNER TO THE BOILER (B)
Before securing the burner to the boiler, check through
the blast tube opening to make sure that the flame sen-
sor probe (flame rod) is correctly set in position, as
shown in (C).
Now detach the combustion head from the burner, fig.
(B):
- loosen the four screws 3) and remove the cover 1);
- disengage the swivel joint 7) from the graduated sector
8);
- remove the screws 2) from the slide bars 5);
- remove the two screws 4) and pull the burner back on
slide bars 5) by about 4”;
- disconnect the wires from the flame rod and the elec-
trode and then pull the burner completely off the slide
bars.
Secure the flange 11)(B) to the boiler plate, inserting the
gasket 9)(B). 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 airtight.
If you noticed any irregularities in the positions of the
flame rod or ignition electrode during the check men-
tioned above, remove screw 1)(D), extract the internal
part 2)(D) of the head and set up the two components
correctly.
IGNITION PILOT ADJUSTMENT
Place the pilot and electrode as shown in fig. (C).
The pilot works correctly at pressures ranging from 5 -
12” WC.
Important
To set the pilot without main burner operaton, proceed
as follows:
- Move the jumper from terminals "30-V11" to terminals
"30-VP", as given in fig. (E), this way the main valve is
cut out.
- With the burner in the manual position, hold the air
damper in the minimum position and make the setting.
- When the setting is correct, replace the jumper on “30-
V11”.
(C)
A B C
9
1/16
“ 12
25/32
“ - 14
1/2
“
5/8
W
D455
(A)
(E)
Probe
Electrode
(B)
D1706
Ignition
pilot
D2799
(D)
MB - Burner terminal strip
D2800
D2317

8
COMBUSTION HEAD ADJUSTMENT
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 maxi-
mum output developed by the burner.
It is therefore essential to establish this value before pro-
ceeding to set up the combustion head.
There are two adjustments to make on the head:
• outside air R1;
• central air R2.
In diagram (C) find the notch for:
➤ Outside air adjustment R1 (A)
Turn screw 4)(A) until the notch identified is aligned with
the front surface 5)(A) of the connector.
➤ Central air adjustment R2 (B)
Loosen the 3 screws 1)(B) and turn ring 2) until the
notch identified is aligned with index 3). Tighten the 3
screws 1) fully down.
Example
RS 160 /M LN
max. burner output = 5681 MBtu/hr
If we consult diagram (C) we find that for this output the
adjustments are:
• outside air: R1 = notch 8.6;
• central air: R2 = notch 0.
NOTES
• R2 adjustment (diagram C) is an indication only. If
possible, always keep the ring nut closed (notch 0); if air
recovery is required the nut may be opened following
the indications in diagram (C).
• Diagram (C) indicates an optimal regulation for a type
of boiler seen in fig. (B) page 5.
Make sure that the combustion characteristics are satis-
factory and free of pulsations.
Once you have finished setting up the head, refit the
burner to the slide bars 3)(D) at approximately 4” from
the sleeve 4)(D) - burner positioned as shown in fig. (B)
pag. 7 - insert the flame rod cable and the ignition elec-
trode cable and then slide the burner up to the sleeve so
that it is positioned as shown in fig. (D).
Refit screws 2) on slide bars 3) after mounting the
extension bracket and relative extensions.
Secure the burner to the sleeve by tightening screw 1).
Reconnect the swivel joint 7) to the graduated sector 6).
Connect gas train and pilot train as shown in fig. (A)
page 9.
Important
When fitting the burner on the two slide bars, it is advis-
able to gently draw out the high tension cable and flame
detection probe cable until they are slightly stretched.
IMPORTANT: In order to facilitate adjustment,
loosen screw 6)(A), adjust and then tighten.
(A)
(C)
(B)
Notches (Air = Gas)
Burner max output
(D)
D2801
D1707
D2367

9
GAS PIPING
• The main 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).
• The gas safety shut-off valves 5)-6)(A) must be as
close as possible to the burner to ensure gas reaches
the combustion head within the safety time range.
• The pilot gas train must be connected to the gas
attachment 5)(A).
GAS TRAIN (B)
It must be type-approved according to required stand-
ards and is supplied separately from the burner.
Note
See the accompanying instructions for the adjustment of
the gas train.
KEY (A)
1 - Gas input pipe
2 - Manual valve
3 - Pressure regulator
4 - Low gas pressure switch
5 - 1st safety shut off valve
6 - 2nd safety shut off valve
7 - Standard issue burner with flange gasket
8 - Gas adjustment butterfly valve *
9 - Burner
10 - High gas pressure switch *
* On the burner
ELECTRICAL WIRING
Notes on safety for the electrical wiring
- The electrical wiring must be carried out with the
electrical supply disconnected.
- Electrical wiring must be carried out by qualified
personnel and in compliance with the regulations
currently in force in the country of destination.
Refer to the electrical layouts.
- The manufacturer declines all responsibility for
modifications or connections different from those
shown in the electrical layouts.
- Check that the electrical supply of the burner corre-
sponds to that shown on the identification label and
in this manual.
- Do not invert the neutral with the phase in the elec-
trical supply line.
Any inversion would cause a lockout due to firing
failure.
- The electrical safety of the device is obtained only
when it is correctly connected to an efficient earth-
ing system, made according to current standards.
It is necessary to check this fundamental safety
requirement. In the event of doubt, have the electri-
cal system checked by qualified personnel.
Do not use the gas tubes as an earthing system for
electrical devices.
- The electrical system must be suitable for the max-
imum input power of the device,as indicated on the
label and in the manual, checking in particular that
the section of the cables is suitable for the input
power of the device.
- For the main power supply of the device from the
electricity mains:
- - do not use adapters, multiple sockets or exten-
sions;
- - use an omnipolar switch with an opening of at
least
1
/
8
” (overvoltage category) between the con-
tacts, as indicated by the current safety standards.
- Do not touch the device with wet or damp body
parts and/or in bare feet.
- Do not pull the electric cables.
(B)
(A)
D2846
D2438
TYPICAL UL SCHEMATIC GAS PIPING
GAS PILOT LINE
MAIN GAS LINE

10
MOTOR CONNECTION
MOTOR CONNECTION at 208-230 or 460V (E)
WARNING:
Please, pay attention to the indications in case of modifi-
cation of voltage, maintenance, or substitution.
MOTOR CONNECTION at 575V (F)
WARNING:
the motors, manufactured for 575V IE2/Epact voltage,
have the same control box base of the 208-230/460V
motors.
Please pay attention to the indications in case of mainte-
nance or substitution.
REVERSIBLE DIRECTION (G)
WARNING:
If it is necessary to reverse the direction then reverse
the two main supply phases.
ADJUSTMENTS BEFORE FIRST FIRING
Adjustment of the combustion head, and air and gas
deliveries has been illustrated on page 8.
In addition, the following adjustments must also be
made:
- Open manual valves up-stream from the gas train.
- Adjust the low gas pressure switch to the start of the
scale (A).
- Adjust the high gas pressure switch to the end of the
scale (B).
- Adjust the air pressure switch to the zero position of
the scale (C).
- Purge the air from the gas line.
Fit a U-type manometer (D) to the gas pressure test
point on the sleeve.
The manometer readings are used to calculate the
MAX. burner power using the diagram on page 6.
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.
(D)
(A)
LOW GAS PRESSURE SWITCH AIR PRESSURE SWITCHHIGH GAS PRESSURE SWITCH
(B) (C)
D2368
IE2/Epact
U2 V2 W2
U3 V3 W3
U1 V1 W1
S8379
U2 V2 W2
U3 V3 W3
U1 V1 W1
S8380
~ ~ ~ ~ ~ ~
460V 208-230V
(E)
S8382
~ ~ ~
575V
(F)
  
  

S8381
L1 L2
(G)

11
SERVOMOTOR
The servomotor gives simultaneous regulation of the air
damper through the variable cam profile 4)(F) and the
gas butterfly valve.
It rotates by 130° in approx. 35 s.
The factory settings must not be changed for the first fir-
ing, just check that they comply with the details below.
To open the servomotor, remove the screws and pull the
cover outward, fig. (A).
CAMS AND TRIM POTENTIOMETERS FUNC-
TIONS
Cam 1: 130°
Limits rotation towards maximum for gas.
Cam 2: 0°
Limits rotation towards minimum, air damper closed on
stand by.
Cam 3: 20°
Limits gas ignition position.
Cams 4 - 5 - 6 - 7 - 8: not used
Trim potentiometer MAX
Limits maximum modulation.
It must be set near the stroke end (cam 1) to exploit as
far as possible the variable profile cam and maximum
opening of the gas butterfly valve.
Trim potentiometer MIN
Limits minimum modulation.
It must be set near the stroke end (cam 2) to exploit as
far as possible the variable profile cam.
Trim potentiometer POS
Limits an intermediate operating position between MAX
and MIN, supplying power to the "P" terminal in the ser-
vomotor (through an external command). This function
cuts out any external signals.
Note
Using the slide switch to select MAX or MIN, the servo-
motor goes into the position for the respective settings of
the MAX and MIN TRIM POTENTIOMETERS.
When the settings are complete, place the slide switch
on OPE.
(D)
(F)
(E)
(C)
1 Servomotor
2 Graduated sector for gas
butterfly valve
3 Index for graduated sector 2
4 Adjustable profile cam
5 Adjustment screws for cam
starting profile
6 Adjustment fixing screws
7 Adjustment screws for cam
and profile
Slide switch
Trim potentiometers
Position jumpers
D2277
D2585
D2594
D2593
(A)
(B)
NO
Figure above shows how the servo-
motor is released to manually check
there is no binding though its motion.
Don’t release the button indi-
cated in this figure: the syn-
cronization of the cams
made in factory would be
changed.
YES

12
BURNER STARTING
Close the control circuit, with the switch in fig. C) in the
AUTO position.
On firing (pilot burner and main valve) turn the switch (C)
to MAN and the switch 1)(E) in the AUT position.
MAXIMUM OUTPUT
Using button (B), "increase output" until it stops, app.
130° (cam 1).
Place the slide switch on MAX and set the relative MAX
trim potentiometer (setting must be very near to 130°) to
exploit as far as possible the variable profile cam 4)(D)
and have the gas butterfly valve on maximum opening,
graduated sector 2) on index 3) fig. (D).
The setting of the gas flow must be made on the gas train
regulator and, if necessary, on the gas valve.
The air setting must be made on the variable profile cam
4)(D) by turning the screws 5), after loosening the screws
6).
MINIMUM OUTPUT
With the slide switch on the OPE position, use button (B)
"decrease output" until it stops at app. 20° (cam 3).
Put the slide switch in the MIN position and set the mod-
ulation minimum using the relative MIN trim potentiome-
ter.
Set the air using the variable profile cam 4)(D).
If a lower modulation minimum is required than the level
set on cam 3 of the servomotor (20°), decrease the cam
setting.
INTERMEDIATE OUTPUTS
With the switch (C) in the AUTO position, the slide switch
in the OPE position and the switch 1)(E) in the MAN po-
sition, move the button 2)(E) in various intermediate lev-
els between maximum and minimum and set the variable
profile cam 4)(D) to achieve optimum combustion, by
turning the screws 5).
If possible, do not change the previously set maximum
and minimum levels.
Check the various setting levels with a combustion anal-
ysis.
Important
Make a progressive adjustment of the profile, without
sharp changes.
When the setting is complete, lock the cam profile using
screws 6)(D).
Turn the burner off, release the servomotor as shown in
fig. (B) page 11 and manually turn cam 4)(D) to check
there is no binding.
Finally fix the adjustment by turning the screws 6)(D).
(B) (C)
(D)
1 Servomotor
2 Graduated sector for gas butterfly
valve
3 Index for graduated sector 2
4 Adjustable profile cam
5 Adjustment screws for cam starting
profile
6 Adjustment fixing screws
7 Adjustment screws for cam and pro-
file
(A)
Slide switch
Trim potentiometers
Position jumpers
(E)
D791
1 2
D2593
D2594

13
AIR PRESSURE SWITCH (A)
Adjust the air pressure switch after having performed all
other burner adjustments with the air pressure switch set
to the start of the scale (A).
With the burner operating at min. output, increase adjust-
ment pressure by slowly turning the relative dial clock-
wise until the burner locks out.
Then turn the dial 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 dial anti-clockwise
a little bit more.
Attention:
As a rule, the air pressure switch must prevent the forma-
tion of CO.
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 400 ppm.
The air pressure switch may operate in "differential"
operation in two pipe system. If a negative pressure in
the combustion chamber during pre-purging prevents
the air pressure switch from switching, switching may be
obtained by fitting a second pipe between the air pres-
sure switch and the suction inlet of the fan. In such a
manner the air pressure switch operates as differential
pressure switch.
HIGH GAS PRESSURE SWITCH (B)
Adjust the high gas pressure switch after having per-
formed all other burner adjustments with the maximum
gas pressure switch set to the end of the scale (B).
With the burner operating at MAX output, reduce the
adjustment pressure by slowly turning the adjustment
dial anticlockwise until the burner locks out.
Then turn the dial clockwise by 0.8” WC and repeat
burner firing.
If the burner locks out again, turn the dial again clock-
wise by 0.4” WC.
LOW GAS PRESSURE SWITCH (C)
Adjust the low gas pressure switch after having per-
formed all the other burner adjustments with the pressure
switch set at the start of the scale (C).
With the burner operating at MAX output, increase ad-
justment pressure by slowly turning the relative dial
clockwise until the burner locks out.
Then turn the dial anti-clockwise by 0.8” WC and repeat
burner starting to ensure it is uniform.
If the burner locks out again, turn the dial anti-clockwise
again by 0.4” WC.
FLAME PRESENT CHECK (D)
The burner is fitted with an ionisation (flame rod) system
which ensures that a flame is present. The minimum
current for reliable operation is 6 µA (see manufacturers
documentation). The burner provides a much higher cur-
rent, so that controls are not normally required. How-
ever, if it is necessary to measure the ionisation current,
disconnect the plug-socket 7)(A)p.4 on the ionisation
probe cable and insert a direct current microamperome-
ter with a base scale of 100 µA. Carefully check polari-
ties.
(A)
AIR PRESSURE SWITCH
(B)
HIGH GAS PRESSURE SWITCH
(C)
LOW GAS PRESSURE SWITCH
(D)
DA
D2548
D2547
D2547
D1711

14
MAINTENANCE
Combustion
The optimum calibration of the burner requires an analy-
sis of the flue gases. Significant differences with respect
to the previous measurements 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.
Flame inspection window
Clean the flame inspection window (A).
Combustion head
Open the burner and make sure that all components of
the combustion head are in good condition, not
deformed by the high temperatures, free of impurities
from the surroundings and correctly positioned. If in
doubt, disassemble the elbow fitting 5)(B).
Servomotor
Disengage the cam 4)(D)p. 12 from the servomotor and
turn it backwards and forwards by hand to make sure it
moves freely.
Burner
Check for excess wear or loose screws in the mecha-
nisms controlling the air damper and the gas butterfly
valve. Also make sure that the screws securing the elec-
trical leads in the burner terminal strip are fully tight-
ened.
Clean the outside of the burner, taking special care with
the swivel joints and cam.
Combustion
Adjust the burner if the combustion values found at the
beginning of the operation do not comply with the regu-
lations in force, or do not correspond to good combus-
tion. Record the new combustion values; they will be
useful for subsequent controls.
TO OPEN THE BURNER (B):
- Switch off the electrical power.
- Loosen screws 1) and withdraw cover 2).
- Disengage the swivel joint 7) from the graduated sec-
tor 8).
- Fit the two extensions onto the slide bars 4).
- Remove screws 3), and pull the burner back by about
4” on the slide bars 4). Disconnect the probe and
electrode leads and then pull the burner fully back.
Now extract the gas distributor 5) after having removed
the screw 6) and disconnecting the pilot gas line.
TO CLOSE THE BURNER (B):
- Push the burner until it is about 4” from the sleeve.
- Re-connect the leads and slide in the burner until it
comes to a stop.
- Refit screws 3), and pull the probe and electrode
leads gently out until they are slightly stretched.
- Re-couple the swivel joint 7) to the graduated sector
8).
- Remove the two extensions from the slide bars 4).
- Connect the pilot gas line.
(A)
FLAME INSPECTION WINDOW
(B)
OPENING THE BURNER
D709
D2369

15
BURNER OPERATION
BURNER STARTING
• Load control close.
Fan motor starts.
• Servomotor starts:
130° rotation to right, until contact is made on cam
1)(A) page 12.
The air damper is positioned to MAX. output.
• Pre-purge stage with air delivery at MAX. output.
• After pre-purge stage, servomotor rotates to left up to
the angle set on cam 3)(A) page 12 for MIN. output.
• The air damper and the gas butterfly are positioned to
MIN. output.
• Ignition electrode strikes a spark.
• Pilot valve opens. The pilot flame is ignited.
• After about 12 s the main flame ignites and starting
cycle ends.
STEADY STATE OPERATION
At the end of the starting cycle, the servomotor control
then passes to the load control for boiler pressure or
temperature.
(The control box continues, however, to check that the
flame is present and that the air pressure switch is in the
correct position.)
• If the temperature or pressure is low, the burner pro-
gressively increases its output to the MAX. value.
• If the temperature or pressure is high, the burner pro-
gressively decreases its output to the MIN. value.
And so on.
• The burner locks out when demand for heat is less
than the heat supplied by the burner at min. output.
Load control opens. The servomotor returns to the 0°
angle limited by contact with cam 2. The air damper
closes completely to reduce thermal dispersion to a
minimum.
Every time output is changed, the servomotor automati-
cally modifies gas delivery (gas butterfly valve) and air
delivery (fan air damper).
Switching times are given in seconds, in the burner
startup sequence.
Legend for the times
t1 Pre-purge time with air damper open
t2 Safety time
t3 Pre-ignition time, short (ignition transformer on
terminal 16)
t4 Interval between start of t2 and release of valve
at terminal 19
t5 Interval between end of t4 and release of load
controller or valve at terminal 20
t5 Running time of air damper into OPEN position
t6 Running time of air damper into low-flame posi-
tion (MIN)
t7 Permissible after-burn time
t8 Interval until OPEN command for the air damper
is given
FIRING FAILURE
If the burner does not fire, it locks out within 2.5 seconds
from opening the pilot valve and then within 5 seconds
from opening the main valves.
BURNER FLAME GOES OUT DURING OPERATION
If the flame should accidentally go out during operation,
the burner will lock out within 1s.
LFL 1.335 Series 01
t1
t2
t3
t4
30
2
4
20
t5
t6
t7
t8
optional
optional
12
4
(A)
Full Modulation
D2273
Low - High
D2274
(B)
LFL 1.335 Series 01

16
BURNER FAULTS
Control program under fault
conditions and lock-out
indication
In case of any disturbance, the sequence mechanism stops and with it the lock-out indicator. The symbol
above the reading mark of the indicator gives the type of disturbance:
No start, e.g. because one contact is not closed. Lock-out during or after control program sequence
due to extraneous light (e.g. non-extinguished flames, leaking fuel valves, defects in the flame
supervision circuit, etc.)
Interruption of startup sequence, because the OPEN signal has not been delivered to terminal 8
by limit switch “a”. Terminals 6, 7 and 14 remain under voltage until the fault has been corrected!
Lockout, because there is no air pressure indication at the beginning of air pressure control.
Every air pressure failure after this moment in time leads to lock-out, too!
Lock-out due to a fault in the flame supervision circuit.
Interruption of startup sequence, because the position signal for the low-flame position has not
been delivered to terminal 8 by auxiliary switch “m”. Terminals 6, 7 and 14 remain under voltage
until the fault has been corrected!
Lock-out, because no flame signal is present after completion of the (1st) safety time.
Lock-out, because no flame signal has been received on completion of the 2nd safety time (flame
signal of the main flame with interrupted pilot burners).
Lock-out, because the flame signal has been lost during burner operation.
If lock-out occurs at any other moment in time between the start and the pre-ignition which is not marked by
a symbol, this is usually caused by a premature, i.e. faulty flame signal, e.g. caused by a self-igniting UV
tube.
LFL 1.335 Series 01
P
1
2

17
PROCEDURE TO REFER BURNER OPERATING CONDITION IN HIGH ALTITUDE PLANTS
- Find the corrected burner capacity for the plant’s altitude in chart 1 and the corrected pressure in chart 2.
- Check in the firing rate graph of the burner (page 5), if the working point defined by the values above is within the range limits.
If not, higher burner size is needed.
Reference conditions (Charts 1-2): Ambient temperature 68 °F (20 °C) - Barometric pressure 394” WC (1000 mbar) - Altitude 328 ft a.s.l. (100 m a.s.l.)
Note
Charts are based only on altitude variation
(reference temperature = 68°F , 20°C)
To get the combined correction in case of different
air temperature, a compensation of 1000 ft each
20°F (305 m each 11°C) is applicable.
Example
Rated capacity = 3000 MBtu/hr - Rated air pressure = 1.5”w.c.
Real altitude = 5000 ft - Real temperature = 108°F
∆= 108°F - 68°F (reference temp.) = 40°F (equivalent 2000 ft variation)
Proceeding as descripted above and considering a “virtual altitude” of (5000 + 2000) ft:
- the corrected capacity is 3847 MBtu/hr;
- the corrected burner air pressure is 1.92.
Burner RS 160/M LN is OK
'
m. a.s.l. 0 100 305 610 915 1220 1525 1830 2135 2440
ft a.s.l 0 328 1000 2000 3000 4000 5000 6000 7000 8000
500
494 500 512 530 551 571 593 616 641 669
1000
987 1000 1023 1061 1101 1142 1186 1232 1282 1337
1500
1481 1500 1535 1591 1652 1713 1778 1848 1924 2006
2000
1974 2000 2046 2121 2202 2284 2371 2464 2565 2675
2500
2468 2500 2558 2652 2753 2855 2964 3079 3206 3343
3000
2962 3000 3069 3182 3303 3425 3557 3695 3847 4012
3500
3455 3500 3581 3712 3854 3996 4149 4311 4488 4680
4000
3949 4000 4092 4243 4404 4567 4742 4927 5130 5349
4500
4442 4500 4604 4773 4955 5138 5335 5543 5771 6018
5000
4936 5000 5116 5303 5505 5709 5928 6159 6412 6686
5500
5429 5500 5627 5834 6056 6280 6520 6775 7053 7355
6000
5923 6000 6139 6364 6606 6851 7113 7391 7694 8024
6500
6417 6500 6650 6894 7157 7422 7706 8006 8335 8692
7000
6910 7000 7162 7425 7708 7993 8299 8622 8977 9361
7500
7404 7500 7673 7955 8258 8564 8892 9238 9618 10029
8000
7897 8000 8185 8485 8809 9135 9484 9854 10259 10698
8500
8391 8500 8697 9016 9359 9705 10077 10470 10900 11367
9000
8885 9000 9208 9546 9910 10276 10670 11086 11541 12035
9500
9378 9500 9720 10076 10460 10847 11263 11702 12183 12704
10000 9872 10000 10231 10607 11011 11418 11855 12318 12824 13373
Average barometric
Pressure
(
20°C
)
mbar 1013 1000 977,4 942,8 908,2 875,8 843,5 811,85 779,8 747,8
Average barometric
Pressure (68°F)
"w.c. 399 394 385 371 358 345 332 320 307 294
Rated Capacity
A
ltitude
CORRECTED BURNER CAPACITY ACCORDING TO ALTITUDE
1
m. a.s.l. 0 100 305 610 915 1220 1525 1830 2135 2440
ft a.s.l 0 328 1000 2000 3000 4000 5000 6000 7000 8000
0,50
0,49 0,50 0,51 0,53 0,55 0,57 0,59 0,62 0,64 0,67
1,00
0,99 1,00 1,02 1,06 1,10 1,14 1,19 1,23 1,28 1,34
1,50
1,48 1,50 1,53 1,59 1,65 1,71 1,78 1,85 1,92 2,01
2,00
1,97 2,00 2,05 2,12 2,20 2,28 2,37 2,46 2,56 2,67
2,50
2,47 2,50 2,56 2,65 2,75 2,85 2,96 3,08 3,21 3,34
3,00
2,96 3,00 3,07 3,18 3,30 3,43 3,56 3,70 3,85 4,01
3,50
3,46 3,50 3,58 3,71 3,85 4,00 4,15 4,31 4,49 4,68
4,00
3,95 4,00 4,09 4,24 4,40 4,57 4,74 4,93 5,13 5,35
4,50
4,44 4,50 4,60 4,77 4,95 5,14 5,33 5,54 5,77 6,02
5,00
4,94 5,00 5,12 5,30 5,51 5,71 5,93 6,16 6,41 6,69
5,50
5,43 5,50 5,63 5,83 6,06 6,28 6,52 6,77 7,05 7,35
6,00
5,92 6,00 6,14 6,36 6,61 6,85 7,11 7,39 7,69 8,02
6,50
6,42 6,50 6,65 6,89 7,16 7,42 7,71 8,01 8,34 8,69
7,00
6,91 7,00 7,16 7,42 7,71 7,99 8,30 8,62 8,98 9,36
7,50
7,40 7,50 7,67 7,96 8,26 8,56 8,89 9,24 9,62 10,03
8,00
7,90 8,00 8,18 8,49 8,81 9,13 9,48 9,85 10,26 10,70
8,50
8,39 8,50 8,70 9,02 9,36 9,71 10,08 10,47 10,90 11,37
9,00
8,88 9,00 9,21 9,55 9,91 10,28 10,67 11,09 11,54 12,04
9,50
9,38 9,50 9,72 10,08 10,46 10,85 11,26 11,70 12,18 12,70
10,00 9,87 10,00 10,23 10,61 11,01 11,42 11,86 12,32 12,82 13,37
Average barometric
Pressure
(
20°C
)
mbar 1013 1000 977,4 942,8 908,2 875,8 843,5 811,85 779,8 747,8
Average barometric
Pressure (68°F)
"w.c. 399 394 385 371 358 345 332 320 307 294
Rated Pressure
A
ltitude
CORRECTED BURNER AIR PRESSURE ACCORDING TO ALTITUDE
2

18
Appendix - Spare parts
25
18
27
42
41
73
5
23
68
70
49
51
65
69
24
62
22
6
19
13
52
1
2
29
12
9
17
21
20
4
3
44
28
48
50 65
66 63
65 64
14
8
7
39
38
36
30
31
40
32
10
37
33
35
34
54
53
56
57
59
58
55
61
6045
16 45 46
71 72 67
47 65
11
26
74
75
28
43
5
1