Nu-Way NDF 35 Instruction Manual

Installation & Maintenance Manual
NDF 35 - 100
Dual Fuel Burner
11/12
Tel:[phone] Fax: [phone] Email: [email protected] Web: www.nu-way.co.uk

Page 2of 64 NDF 35-180 11/12
Contents
INTRODUCTION........................................................................................................................................ 3
Operating Mode........................................................................................................................................ 4
Site Conditions And Services..................................................................................................................... 10
Unpacking & Assembly ............................................................................................................................. 13
INSTALLATION....................................................................................................................................... 17
BURNER CONTROL AND OPERATION............................................................................................... 17
Air Controls:........................................................................................................................................... 17
Gas Controls:.......................................................................................................................................... 18
Oil Controls –Twin Pressure Jet Oil Burners........................................................................................ 25
Oil Controls –Single Spill Back Oil Burners ........................................................................................ 26
Control Panel.............................................................................................................................................. 32
Modulating Controller............................................................................................................................ 36
Commissioning........................................................................................................................................... 39
Inspection ............................................................................................................................................... 39
Oil Commissioning................................................................................................................................. 40
Gas Commissioning................................................................................................................................ 44
Final commissioning stages - oil & gas.................................................................................................. 47
Fuel Changeover Procedure ................................................................................................................... 48
Routine Safety Checks ........................................................................................................................... 49
Routine Maintenance.................................................................................................................................. 50
Fault Finding .............................................................................................................................................. 51
Spare Parts.................................................................................................................................................. 53
APPENDIX ................................................................................................................................................ 54
Oil Commissioning Sheet....................................................................................................................... 58
Gas Commissioning Sheet...................................................................................................................... 59
Performance Envelopes.............................................................................................................................. 60
IMPORTANT-SAFETY
IT IS ESSENTIAL THAT THE FOLLOWING INSTRUCTIONS AND ADJUSTMENTS ARE CARRIED OUT BY QUALIFIED ENGINEERS THAT
ARE EXPERIENCED IN FORCED DRAUGHT GAS BURNER COMMISSIONING.IN THE U.K. IT IS A LEGAL REQUIREMENT THAT
ANYONE WORKING ON GAS INSTALLATION,AS DEFINED IN THE “GAS SAFETY (INSTALLATION &USE)REGULATIONS 1994” IS
GAS SAFE REGISTERED (OR WHATEVER REPLACEMENT SCHEME IS IN PLACE AT THE TIME). THE COMPOSITION OF THE FUEL IS
CRITICAL TO THE CORRECT OPERATION AND SAFETY OF THE EQUIPMENT.OPERATION WITH FUELS CONTAINING EVEN TRACE
ELEMENTS OF CERTAIN SUBSTANCES CAN GIVE RISE TO HAZARDOUS CONDITIONS IF YOU HAVE ANY DOUBTS ABOUT THE
SPECIFICATION OF THE FUEL MEETING OUR REQUIREMENTS YOU SHOULD CONSULT YOUR SUPPLIER BEFORE OPERATION.
THE MANUFACTURER CANNOT BE HELD RESPONSIBLE FOR ANY CONSEQUENTIAL DAMAGE,LOSS OR PERSONAL INJURY AS A
RESULT OF FAILURE TO FOLLOW THESE INSTRUCTIONS,OR AS A RESULT OF MISUSE.
EUROPEANBOILEREFFICIENCYDIRECTIVE(B.E.D.)
ALL BURNERS AND BOILER BODIES MARKETED SEPARATELY SHOULD COMPLY WITH EN676 (GAS BURNERS)AND EN303
(HEATING BOILERS). BURNER ADJUSTMENTS MUST BE MADE IN ACCORDANCE WITH BOILER MANUFACTURERS’INSTRUCTIONS,
AND THESE MUST INCLUDE FLUE GAS TEMPERATURES,AVERAGE WATER TEMPERATURE,AND CO2OR O2CONCENTRATION.

Page 3of 64 NDF 35-180 11/12
INTRODUCTION
This manual has been produced to enable users to install, commission and use NDF burners safely and efficiently.
At each stage, the conditions that should be met and the adjustments and other actions that should be carried out
are detailed and the locations of the various components and adjustment mechanisms are identified. Where
appropriate, this information is supported by tables and graphs. Literature on the proprietary components used in
NDF burner systems is available on request.
FEATURES
Developed through extensive field experience in the UK and overseas markets, the NDF series of dual fuel burners
meets all current test authority requirements in these markets and sets new standards inefficient and reliable
operation. NDF burners are designed for flange mounting to the application front plate and they are delivered ready
to install with a pre-wired packaged control system and plug-in gas train.
Burner Capacity
The figures quoted are nominal burner outputs based on net calorific value (NCV).
Burner Model
Capacity (kW)
NDF 35
253 –1026
NDF 50
406 - 1353
NDF 60
496 - 1669
NDF 85
722 –2210
NDF 100
766 –2706
NDF 125
1786 –3247
NDF 150
1380 –4059
NDF 180
1125 –4450
Please refer to the Appendix of this handbook for detailed burner performance data.
Fuel
Burners designated NDFL are suitable for light distillate oil (Class D) and those designated NDFR are suitable for
residual oil (Classes E, F and G). All NDF burners are normally configured for natural gas but versions suitable for
liquefied petroleum gas (LPG) or manufactured gas (towns gas) can be supplied on request. Operation with fuels
containing even trace elements of certain substances can give rise to hazardous conditions if you have any doubts
about the specification of the fuel meeting our requirements you should consult your supplier before operation.
Air Fan Size
To match NDF burners with the appliance, with respect to
both burner output and appliance, resistance, a number of
combustion air fan sizes are available for each model, as
detailed in the table below.
The fan size quoted is the diameter of the fan impellor
(measured in cm) and appears as a suffix to the model
number. For example, a burner designated NDFR 60-34 is a
model 60 for residual fuel oil firing with a 34cm diameter
combustion air fan impellor.
Controls and Safety Systems
NDF burners are fitted with a combustion airflow control and an air/fuel ratio control system which together ensures
smooth starting and optimum operating efficiency.
An air pressure switch provides safe burner shutdown if the combustion air supply becomes insufficient for
complete combustion. The burner’s additional safety systems include for gas pressure monitoring (low and high)
whilst gas firing and low oil temperature monitoring (NDFR) whilst firing on fuel oil. Continuous flame supervision
is provided by an ultraviolet (UV) cell and automatic programming control unit.
Burner Model
Available Fan Sizes
NDF 35
25, 34, 38
NDF 50
28, 34, 38
NDF 60
28, 34, 38
NDF 85
38
NDF 100
38, 41, 44
NDF 125
36, 41, 44
NDF 150
36, 41, 44
NDF 180
44

Page 4of 64 NDF 35-180 11/12
Operating Mode
Standard NDF burners are manufactured for either fully modulating or two-stage (high/low) operation on both fuels.
A special variation of the NDFL 35 to NDFL 100-38 burner is available on request, designated Modulating-
High/Low. In this version, the burner operates in fully modulating mode when firing on gas, and 2 stage (high/low)
mode when firing on oil.
Oil Firing
Two Stage Operation: NDFL burners up to and including the NDFL 100-38 use twin simplex oil nozzles, one for
low fire and both for high fire. The oil nozzles are sized to give a turndown ratio of between 1.8 and 2.0:1.
NDFL burners NDFL 100-41 and larger, together with all NDFR burners are supplied with a system designated
‘Sliding High/Low’ which uses a single spill-back oil nozzle (similar to that employed in the fully modulating mode)
which is constrained to operate at either of two fixed oil flows corresponding to the high and low fire rates. If the
burner has been correctly matched to the appliance, a turndown ratio of up to 3.0:1 may be achieved.
Fully Modulating Operation: All NDF burners manufactured for fully modulating operation use a single spill-back oil
nozzle. If the burner has been correctly matched to the appliance, a turndown ratio of up to 3.0:1 may be achieved.
Gas Firing –All Modes
When gas firing, the fuel gas flow is controlled by an automatic valve which, following commissioning, precisely
matches the fuel flow to the air flow to achieve the required fuel/air ratio at any point in the full turndown range. If
the burner has been correctly matched to the appliance, a turndown ratio between 2.0 and 2.5:1 may be achieved.
Burner Type Nomenclature
NDF burners are divided into two groups, depending on the oil nozzle employed:
Twin Nozzle Pressure Jet Burners
Comprising two stage NDFL burners up to and including the NDFL 100-38.
Single Nozzle Spill-back Burners
Comprising two stage NDFL burners NDFL 100-41 and larger
All fully modulating NDFL burners
All two stage NDFR burners
All fully modulating NDFR burners
Throughout this handbook the burners are referred to by this grouping.

Page 5of 64 NDF 35-180 11/12
FIG 1: BURNER AND COMPONENT IDENTIFICATION FOR
NDF MODULATING BURNER
(MODEL SHOWN NDF 125 SHOWN)
Item
Description
Item
Description
1
Burner Casing
13
Valve Proving Pressure Switch
2
Hinged Extension
14
Modulating Cam Box
3
Flame Tube
15
Valve Proving System
4
Fan Motor
16
Pilot Solenoid Valve
5
Air Inlet
17
Pilot Governor
6
Damper Motor
18
Low Gas Pressure Switch
7
Burner Terminal Panel
19
Flexible Oil Pipe
8
Casing Access Lid
20
Quick Release Oil Couplings
9
High Gas Pressure Switch
21
Pressure Gauges
10
Valve Body
22
Oil Manifold
11
Control Valve
23
Manual Gas Interlock Valve
12
Main Valve
FG
16 17

Page 6of 64 NDF 35-180 11/12
FIG 2
3 12 9
6 5
8
7
4
8
14
10
11 13 10 12
1815
A
B
23
22 20 1921
BURNER
PROJECTION
DC
E

Page 7of 64 NDF 35-180 11/12
FIG 3: BURNER AND COMPONENT IDENTIFICATION FOR
NDF TWO STAGE (H/L) BURNER
(MODEL SHOWN NDF 35 SHOWN)
Item
Description
Item
Description
1
Burner Casing
14
Connection Box
2
Hinged Extension
15
Valve proving system
3
Flame Tube
16
Pilot Solenoid Valve
4
Fan Motor
17
Pilot Governor
5
Damper Motor
18
Low Gas Pressure Switch
6
Burner Control Panel
19
Flexible Oil Pipe
7
Air Inlet
20
Oil Pump
8
Casing Access Lid
21
Pressure Gauge
9
High Gas Pressure Switch
22
Isolation Valve
10
Valve Body
23
Microswitch
11
Control Valve
24
Twin Solenoid Valve
12
Main Valve
25
Oil Manifold
13
Valve Proving Pressure Switch
26
Manual Gas Interlock Valve
20
19
G
F

Page 8of 64 NDF 35-180 11/12
FIG 4
A
B
3
9
21
1
2223
8
56
17
13
16
7
4
18
14
15
26
2
12
BURNER
PROJECTION
D
E
C
25
11
10
24

Page 9of 64 NDF 35-180 11/12
FIG 5: BURNER DIMENSIONS
Twin Pressure Jet Oil Nozzle Burners
NDFL 35-25 to NDFL 100-38 Two Stage (High/Low)
Model
Dimensions (all mm)
A
B
C
D
E
F
G
NDFL 35-25
885
540
165
410
305
686
280
NDFL 35-34
1069
540
165
410
305
686
330
NDFL 35-38
1081
540
165
410
305
686
330
NDFL 50-28
1069
540
165
410
305
800
370
NDFL 50-34
1069
540
165
410
305
800
370
NDFL 50-38
1081
540
165
410
305
800
370
NDFL 60-28
1069
540
165
410
305
800
360
NDFL 60-34
1069
540
165
410
305
800
360
NDFL 60-38
1081
540
165
410
305
800
360
NDFL 80-28
1069
920
165
550
385
1196
360
NDFL 80-34
1069
920
165
550
385
1196
360
NDFL 85-38
1081
920
165
550
385
1196
360
NDFL 100-38
1081
920
165
550
385
1196
372
Single Spill-back Oil Nozzle Burners
NDFR 35 to NDFR 180 Two Stage (Sliding High/Low) & Modulating
NDFL 100-41 to NDFL 180-44 Two Stage (Sliding High/Low)
Model
Dimensions (all mm)
A
B
C
D
E
F
G
NDF 35-25
810
540
280
410
305
686
210
NDF 35-34
967
540
300
410
305
686
260
NDF 35-38
1014
540
300
410
305
686
260
NDF 50-28
967
540
300
410
305
800
260
NDF 50-34
967
540
300
410
305
800
260
NDF 50-38
1014
540
300
410
305
800
260
NDF 60-28
967
540
300
410
305
800
260
NDF 60-34
967
540
300
410
305
800
260
NDF 60-38
1014
540
300
410
305
800
260
NDF 80-28
967
920
300
550
385
1196
260
NDF 80-34
967
920
300
550
385
1196
260
NDF 85-38
1014
920
300
550
385
1196
260
NDF 100-38
1014
920
300
550
385
1196
260
NDF 100-41
1240
920
345
580
416
1196
440
NDF 100-44
1240
920
345
580
416
1196
440
NDF 125-36
1240
920
345
580
416
1196
440
NDF 125-41
1240
920
345
580
416
1196
440
NDF 125-44
1240
920
345
580
416
1196
440
NDF 150-36
1240
920
345
580
416
1210
440
NDF 150-41
1240
920
345
580
416
1210
440
NDF 150-44
1240
920
345
580
416
1210
440
NDF 180-44
1240
920
345
580
416
1210
440

Page 10 of 64 NDF 35-180 11/12
FIG 6: BURNER MOUNTING ARRANGEMENT
45° Hole
Diam. H
NDF35 - NDF100
8 x M10 StudsEquispaced
on 305 mm PCD
Burner
Diam. H mm
NDF35
230
NDF50
230
NDF60
230
NDF80
280
NDF85
280
NDF100
280
NDF125
350
NDF150
350
NDF180
350
45° Hole
Diam. H
NDF125 - NDF180
4 x M20 StudsEquispaced
on 454 mm PCD
Site Conditions And Services
Flue and Chimney Requirements
It is important that;
The flue pipe from the appliance and the joint between this flue and chimney are sealed to prevent leakage
of combustion products.
The flue pipe from the appliance does not protrude into the chimney beyond the inside wall.
The top of the flue or chimney shall be higher than any roof within a radius of 10 metres.
Checks are made to ensure that the chimney is suitable for gas and oil fired appliances and that the
proposed installation complies with all Local Authority and other regulations covering such installations.
The flue must be balanced at the appliance outlet.
If more than one appliance is connected to a common flue or chimney, the cross-section of this flue or
chimney should be adequate for the total volume of combustion products from the appliances.
Plant Room Ventilation
The burner must be supplied with dust free air at sufficient rates for all firing conditions, in accordance with the
appropriate Standards.
Existing Appliances
The appliance should be prepared for the installation of the NDF burner by thorough cleaning, including the
removal of all adhering tar, scale and dirt. An inspection should also be carried out to ensure that the appliance is
in good condition. Any doubt about the suitability of the appliance for dual fuel firing should be referred to the
appliance manufacturer.
Combustion Chamber Conditions
When a burner is fitted to an appliance designed to work under balanced or negative combustion chamber
pressure conditions the over-fire draught must not exceed 0.25 mbar.
Gas Supply
The gas supply pipework to the burner must be appropriate to local conditions and must be constructed and
installed in compliance with appropriate Codes and Standards. It shall be of sufficient size to satisfy the pressure
and volume requirements of the burner under all firing conditions. Checks should be made to ensure that all meters
and other components are appropriately rated for the maximum gas flow rate anticipated.

Page 11 of 64 NDF 35-180 11/12
It is essential that a 90 degree manual isolating valve is fitted upstream of the gas control train to allow the burner
to be isolated for maintenance. The size of this valve should not be less that of the burner control train to avoid a
restriction in gas flow.
Gas Boosters
When a gas booster is used, the gas pressure at the booster inlet must not fall below 10 mbar under any
conditions. A low gas pressure switch must be fitted on the upstream side of the booster to prevent it starting if the
supply pressure is insufficient.
An additional pressure switch should be used to monitor the pressure downstream of the booster and prevent the
burner going to high fire if the pressure is insufficient.
It should be noted that CE marked burners fitted with a low gas pressure switch will not run if the gas pressure
from the booster is insufficient. This is due to the low gas pressure switch being set to safeguard combustion
quality at the high fire setting. In this situation the booster outlet pressure switch will have no bearing on the burner
control, but can be used to indicate booster failure.
The booster should be installed as near to the burner as possible. It should be positioned on a firm, flat, horizontal
surface using anti-vibration mountings. All connecting pipework shall be well supported and accurately positioned
in order to avoid stressing the booster casing. Flexible connectors, which reduce both pipework stress and
transmitted noise, must be fitted. The gas supplier should be asked to recommend the size of the pipework
between the meter and the booster to ensure that the required pressure and flow are available.

Page 12 of 64 NDF 35-180 11/12
FIG 7: A TYPICAL PUMPED OIL RING MAIN
TS
PS
TS PS
80 Mesh
Filter
Duplex
HeatingSet
Duplex
Pump Set
Oil Storage
Tank FeedsTo Burners
(See Note 4)
ReturnsFrom Burners
(If Fitted)
Sludge
Valve Drain Valve
TS
TS
Tank Heater
Outflow
Heater
40 Mesh
Filter
Pressure
Relief
Valves Manual Valves
Pressure
Regulator
Manual
Valve
Thermo-
stat Pressure
Switch
Non Return
Valve
Notes:
1. Duplex pumps and heaters are recommended for continuity and serviceability.
2. Line heaters are recommended for Class F & G fuels, but are not normally necessary for Class E fuel.
3. Pre-heating Class D fuel is not normally required, but a minimum temperatyre of 5°C should be
maintained and all exposed pipework must be lagged.
4. If a shut-off valve is fitted in the supply line to the burner oil pump inlet then a pressure relief valve
MUST also be fitted to prevent damage should the shut-off valve be inadvertently left closed during the
burner start-up cycle. the relief valve must be set at 0.70 kg/cm2(10 psi) above the normal supply
pressure.

Page 13 of 64 NDF 35-180 11/12
Oil Supply
The oil supply pipework to the burner must be appropriate to local conditions and must be constructed and
installed in compliance with appropriate Codes and Standards. It shall be of sufficient size to satisfy the pressure
and volume flow requirements of the burner under all firing conditions. Checks should be made to ensure that all
meters and other components are appropriately rated for the maximum oil flow rate anticipated. Galvanised steel
pipe should not be used. The supply pipework should include an appropriate filter. The final connection to the oil
pump inlet port should be made using the flexible pipes supplied with the burner.
NDFL burners may employ a pumped ring main (see Fig 6) or gravity feed oil supply system. Where a gravity feed
system is used it should be designed and sized such that the oil pressure at the pump inlet is not less than 350
mbar and not more than 689 mbar. A two-pipe system must be used. It is important to ensure that the return pipe is
not obstructed as this may result in damage to the pump.
Where it is thought desirable, a pumped ring main (see Fig 6) of appropriate capacity may be used for NDFL
burners and such a system is essential where the burner is to operate on residual oil (NDFR burners). The
capacity of the ring main pump should be at least 1.25 times that of the burner pump(s) that it is required to supply.
In the case of NDFR burners the pipework and oil storage tank should be insulated, trace heated and
thermostatically controlled in accordance with the data shown in table 2.
FIG 8: Oil Handling Temperatures and Pressures
Fuel Handling Temperatures (oC)
Fuel Delivery Pressures
(At inlet to burner oil pump)
Fuel
Class
Viscosity
(seconds)
Min from tank
Burner Inlet
Atomising
Kg/cm2
Psi
D
35
Minimum 5 recommended
0.35 to 0.7
72.5 max
E
200
16
16
82
4 to 5
57 to 71
F
960
30
43
110
1500
36
65
118
G
3500
50
82
132
4200
55
86
140
Electrical Power Supply
A three-phase 50 Hz supply is required. Power requirements are listed in Table 3 and Table 4. The power supply
provided must comply with all relevant Codes and Standards.
Unpacking & Assembly
To safeguard against damage in transit, NDF burners are supplied in partly assembled form.
Twin Nozzle Pressure Jet Burners (NDFL35-25 to 100-38 2 Stage (High/Low))
NDFL burner systems comprise two units:
1. The burner body, complete with control package, hinged extension and flame tube assembly.
2. The gas control train.
To assemble the burner:
1. Fit the gas control train to the burner body using the gasket supplied, ensuring that the gasket is fitted
correctly with all holes corresponding with those on the burner flange.
2. Connect the combustion air impulse pipe from the SKP75 air/gas ratio controller to the left side of the
hinged extension.
3. Connect the multi-pin plug on the gas valve train to the socket on the rear of the control package.
Note: In some circumstances it may be advisable to fit the burner casing to the appliance before attaching the gas
control train. It is recommended that lifting gear should be employed if necessary.

Page 14 of 64 NDF 35-180 11/12
Single Spill-back Burners
(NDFL Modulating Burners, NDFR Burners)
NDFR burner systems comprise four units:
1. The burner body, complete with hinged extension and flame tube assembly.
2. The gas control train.
3. The oil pump
oThe oil pump unit (NDFL)
oThe oil pumping and heating unit (NDFR).
4. A free-standing or wall-mounted control panel).
To assemble the burner:
1. Fit the gas control train to the burner body using the gasket supplied, ensuring that the gasket is fitted
correctly with all holes corresponding with those on the burner flange.
2. Connect the combustion air impulse pipe from the SKP75 air/gas ratio controller to the left side of the
hinged extension.
3. Connect the multi-pin plug on the gas valve train to the socket on the rear of the burner mounted terminal
panel.
4. Place and secure the oil pump/pumping and heating unit in the desired position. The floor mounting
arrangements are shown in Figure 24 (residual fuels) and Figure 25 (distillate fuels). Connect the unit to
the burner pipework using the flexible connectors provided.
5. Fix the control panel in an appropriate position and make the electrical connections to the burner package
and oil pump unit, as shown in the wiring diagram contained in the instruction pack attached to the burner.
Note: In some circumstances it may be advisable to fit the burner casing to the appliance before attaching the gas
control train. It is recommended that lifting gear should be employed if necessary.
FIG 9: ELECTRICAL POWER REQUIREMENTS: TWIN
PRESSURE JET OIL BURNERS
(NDFL 35-25 to NDFL 100-38 Two Stage Operation)
Burner
Fan Motor
kW/hp
Start
Current
A/Phase
FLC
A/Phase
Cable
Size
(mm2)
HRC
Fuse
(A)
NDF 35-25
1.1/1.5
15.8
2.7
1.0
10
NDF 35-34
2.2/3.0
29.3
5.0
1.5
16
NDF 35-38
3.0/4.0
38.6
6.6
2.5
20
NDF 50-28
2.2/3.0
29.3
5.0
1.5
16
NDF 50-34
3.0/4.0
38.6
6.6
2.5
20
NDF 50-38
4.0/5.5
49.7
8.5
2.5
25
NDF 60-28
2.2/3.0
29.3
5.0
1.5
16
NDF 60-34
4.0/5.5
49.7
8.5
2.5
25
NDF 60-38
4.0/5.5
49.7
8.5
2.5
25
NDF 80-28
3.0/4.0
38.6
6.6
2.5
20
NDF 80-34
4.0/5.5
49.7
8.5
2.5
25
NDF 85-38
5.5/7.5
66.1
11.3
2.5
32
NDFL 100-38
7.5/10.0
88.9
15.2
4.0
32

Page 15 of 64 NDF 35-180 11/12
Special Compact Burner Arrangement
Depending on the burner model and application, a special compact version of NDFL Modulating and NDFR
burners can be supplied. These burner models are supplied to special order only and are delivered with the oil
pumping (pumping and heating) equipment mounted under the burner throat.
If additional appliance control requirements are not specified, then the burner control panel can also be burner
mounted. The equipment is thus delivered as a packaged arrangement with all of the interconnecting oil pipework
and electrical control connections pre-made. The gas control will be supplied loose.
IMPORTANT:
The NDF compact burner, in particular the NDFR series, will be heavier than its standard counterpart.
This must be taken into consideration when fitting the burner to the appliance.
It is strongly recommended that lifting gear should be employed when carrying out this task.
FIG 10: ELECTRICAL POWER REQUIREMENTS: SINGLE
SPILL-BACK NOZZLE DISTILLATE OIL BURNERS
(NDFL 35-25 to NDFL 180-44 Modulating and Two Stage Operation)
Burner
Fan
Motor
kW/hp
Pump
Motor
kW/hp
Start
Current
A/Phase
FLC
A/Phase
Cable
Size
(mm2)
HRC
Fuse
(A)
NDF 35-25
1.1/1.5
0.55/0.75
25.2
4.3
1.5
16
NDF 35-34
2.2/3.0
0.55/0.75
38.6
6.6
2.5
20
NDF 35-38
3.0/4.0
0.55/0.75
48.0
8.2
2.5
25
NDF 50-28
2.2/3.0
1.1/1.5
45.0
7.7
2.5
25
NDF 50-34
3.0/4.0
1.1/1.5
54.4
9.3
4.0
32
NDF 50-38
4.0/5.5
1.1/1.5
65.5
11.2
4.0
32
NDF 60-28
2.2/3.0
0.75/1.0
41.0
7.0
2.5
25
NDF 60-34
4.0/5.5
0.75/1.0
61.5
10.5
4.0
32
NDF 60-38
4.0/5.5
0.75/1.0
61.5
10.5
4.0
32
NDF 80-28
3.0/4.0
0.75/1.0
50.4
8.6
2.5
25
NDF 80-34
4.0/5.5
0.75/1.0
61.5
10.5
4.0
32
NDF 85-38
5.5/7.5
0.75/1.0
77.9
13.3
4.0
32
NDF 100-38
7.5/10.0
1.5/2.0
101.3
17.3
4.0
40
NDF 100-41
11.0/15.0
1.5/2.0
97.0
25.3
6.0
40
NDF 100-44
11.0/15.0
1.5/2.0
97.0
25.3
6.0
40
NDF 125-36
7.5/10.0
1.5/2.0
101.3
17.3
4.0
40
NDF 125-41
11.0/15.0
1.5/2.0
97.0
25.3
6.0
40
NDF 125-44
11.0/15.0
1.5/2.0
97.0
25.3
6.0
40
NDF 150-36
11.0/15.0
1.5/2.0
97.0
25.3
6.0
40
NDF 150-41
11.0/15.0
1.5/2.0
97.0
25.3
6.0
40
NDF 150-44
15.0/20.0
1.5/2.0
123.6
32.9
10.0
50
NDF 170-44
15.0/20.0
1.5/2.0
123.6
32.9
10.0
50
NDF 180-44
15.0/20.0
1.5/2.0
123.6
32.9
10.0
50

Page 16 of 64 NDF 35-180 11/12
FIG 11: ELECTRICAL POWER REQUIREMENTS: SINGLE SPILL-BACK
NOZZLE RESIDUAL OIL BURNERS WITH OIL PRE-HEATER
(NDFL 35-25 to NDFL 180-44 Modulating and Two Stage Operation)
Burner
Pump
Motor
kW/hp
Start
Current
A/Phase
FLC
A/Phase
Cable
Size
(mm2)
HRC
Fuse
(A)
Pre-
heater
kW
Cable
Size
(mm2)
NDF 35-25
1.1/1.5
31.6
14.0
4.0
32.0
6.0
1.5
NDF 35-34
1.1/1.5
45.0
16.4
4.0
32.0
6.0
1.5
NDF 35-38
1.1/1.5
54.4
18.0
4.0
40.0
6.0
1.5
NDF 50-28
1.1/1.5
45.0
18.5
4.0
40.0
7.5
1.5
NDF 50-34
1.1/1.5
54.4
20.1
4.0
40.0
7.5
1.5
NDF 50-38
1.1/1.5
65.5
22.0
4.0
40.0
7.5
1.5
NDF 60-28
1.1/1.5
45.0
18.5
4.0
40.0
7.5
1.5
NDF 60-34
1.1/1.5
65.5
22.0
4.0
40.0
7.5
1.5
NDF 60-38
1.1/1.5
65.5
22.0
4.0
40.0
7.5
1.5
NDF 80-28
1.5/2.0
59.7
21.0
4.0
40.0
7.5
1.5
NDF 80-34
1.5/2.0
70.8
22.9
4.0
40.0
7.5
1.5
NDF 85-38
1.5/2.0
87.2
25.7
6.0
40.0
7.5
1.5
NDF 100-38
1.5/2.0
101.2
28.1
6.0
40.0
7.5
1.5
NDF 100-41
1.5/2.0
97.0
36.1
10.0
50.0
7.5
1.5
NDF 100-44
1.5/2.0
97.0
36.1
10.0
50.0
7.5
1.5
NDF 125-36
1.5/2.0
101.2
30.3
6.0
40.0
9.0
2.5
NDF 125-41
1.5/2.0
97.0
38.3
10.0
50.0
9.0
2.5
NDF 125-44
1.5/2.0
97.0
38.1
10.0
50.0
9.0
2.5
NDF 150-36
1.5/2.0
97.0
42.7
10.0
63.0
12.0
4.0
NDF 150-41
1.5/2.0
97.0
42.7
10.0
63.0
12.0
4.0
NDF 150-44
1.5/2.0
123.7
50.3
16.0
80.0
12.0
4.0
NDF 170-44
1.5/2.0
123.7
50.3
16.0
80.0
12.0
4.0
NDF 180-44
1.5/2.0
123.7
50.3
16.0
80.0
12.0
4.0
NOTE: Burner fan motors up to and including 7.5 kW are started D.O.L.
Above 7.5 kW Star/Delta starters are fitted.

Page 17 of 64 NDF 35-180 11/12
INSTALLATION
General
Ensure that the appliance is suitable for the heat input of the burner. If there is any doubt in this area reference
should be made to the appliance manufacturer. Detailed burner performance data are presented in the Appendix
of this handbook.
Fitting to the Appliance
If the burner is to be fitted to a new appliance, refer to the appliance manufacturer’s recommendations.
If the burner is to be fitted to an existing appliance, a mounting flange must be provided as detailed in the Section
on Burners and Components identification. Ensure that the joint between the burner and the mounting flange is
sealed effectively using the gasket provided.
The flame tube should be flush with the inner face of the appliance combustion chamber. Up to 10mm protrusion
may be acceptable (refer to the appliance manufacturer) however, it is not generally permissible for the flame tube
to sit within the appliance firing tunnel.
Special extensions may be specified by the appliance manufacturer, for example in the case of a reverse flame
boiler.
Electrical Power Connection
Connect a three-phase, 50Hz electrical supply to the burner, observing all applicable Codes and Standards. The
electrical connections required are shown in the wiring diagram contained in the instruction pack attached to the
burner. These diagrams also show the external auxiliary control connections which must be made. If the burner is
supplied as part of a packaged appliance/burner unit, refer to the appliance manufacturer’s instructions.
BURNER CONTROL AND OPERATION
All personnel concerned with commissioning and/or operation of NDF burners should familiarise themselves with
the information presented in this Section.
Air Controls:
Air Regulator:
NDF 35-25 to NDF 100-38
The flow of combustion air into the burner is controlled by a single adjustable air damper blade located within the
air damper casting on the right-hand side (in all cases, such descriptions refer to the system as viewed from the
rear) of the burner.
NDF 100-41 –NDF 180-44
The flow of combustion air into the burner is controlled by a multiple-aperture rotary type damper, fitted to the
burner casing within the air inlet silencer on the right-hand side of the burner.
Air Damper Motor:
In all cases, the air damper is controlled by a servomotor containing adjustable limit switches for the low and high
fire positions.
Twin Pressure Jet Burners
On twin pressure jet burners a Berger Lahr STM6 5 cam motor is used, as shown in Figure 12. A fully closed
position is provided to prevent air flowing through the appliance when the burner is not in operation. On these
burners, the servomotor is mounted on the rear face of the air inlet and directly coupled to the air damper blade.
Single Spill-back Burners
The single spill-back burners employ a Siemens SQM10 motor as shown in Figure 13. This motor
activates the damper through an adjustable cam and cable system, and is mounted above the air inlet
on all models.

Page 18 of 64 NDF 35-180 11/12
Air Diffuser
The air diffuser is fitted to the front of the burner assembly, within the flame tube (refer to the Appendix). The
diffuser controls the combustion air flow and creates a pressure drop across the burner head, promoting good
fuel/air mixing and flame stability.
Air Pressure Switch
The air pressure switch is located on the left side of the burner casing. its function is to ensure that combustion air
flow is adequate under all operating conditions.
Air flow failure at any stage beyond the first few seconds of the pre-purge sequence will result in burner lockout.
Gas Controls:
A typical gas train fitted is shown in Figure 14.
Gas Nozzle
NDF burners utilise a spiked head design with multiple gas tubes fitted with appropriately sized gas restrictors.
Referred to as the “gas nozzle” this is fitted to the front of the burner assembly, within the flame tube (refer to the
Appendix). The number and diameter of the gas tubes in this nozzle are specified in accordance with the rating of
the burner and the gas to be used (refer to the table on the appendix).
High Gas Pressure Switch
A high gas pressure switch is fitted at the outlet of the gas train to ensure that any increase in gas supply pressure
above the level needed to maintain the set conditions results in a safe burner shutdown. In most cases, high gas
pressure would indicate a fault with the air/gas ratio controller.
The pressure switch, which is fitted with an illuminated fault indicator and manual reset button, is factory set to the
maximum value. Final adjustment of the setting of this switch is described in the Section on commissioning.

Page 19 of 64 NDF 35-180 11/12
FIG 12: AIR DAMPER SERVOMOTOR: TWIN PRESSURE JET BURNERS
Model: Schneider (Berger Lahr) STM 6 Q3
Factory Settings
Cam
Function
Setting
(°)
II
Full Air Shut-off
0
V
Low Fire Air
20
I
High Fire Air
60
III
High Flame Oil Valve Out
50
IV
High Flame Oil Valve In
40
Notes:
1. The burner air damper should be set to give optimal combustion whilst firing on oil. When firing gas,
the SKP75 air/gas ratio control valve should be adjusted to give optimal combustion with the same air
damper settings.
2. The fully closed cam (II) is factory set and under normal circumstances should not require further
adjustment.
3. Operation of the low and high fire air switches (cams V and I) is made by manually adjustable cams. A
setting scale is provided at the end of the cam stack for guidance. Adjustments are made using the
screw adjusters situated within the cam disc body,
4. The position at which the main flame oil valve is activated is controlled by adjusting cams III and IV. A
setting should be made to ensure a smooth changeover whilst maintaining good combustion quality.
5. The motor will traverse 90° within a maximum of 6 seconds.

Page 20 of 64 NDF 35-180 11/12
FIG 13: AIR DAMPER SERVOMOTOR: SINGLE SPILL-BACK NOZZLE
BURNERS
Model: Siemens (Landis & Staefa) SQM 10
Disengagement
Lever
Adjusting
Spanner
Factory Settings
Cam
Function
Setting
(°)
1
Gas
Firing
High Fire Air
160
2
Low Fire Air
0
3
Oil
Firing
High Fire Air
160
4
Low Fire Air
0
5
Not Used
6
7
Notes:
1. The servomotor operates both the air damper mechanism and the oil spill adjusting valve via
mechanical cam arrangements mounted on a common shaft within the ‘Modulating Cam Box’.
2. The operation and adjustment of the ‘Modulating Cam Box’ arrangement should be fully understood
before attempting to adjust the motor settings.
3. Cams 1 and 4 represent the low and high limits of the mechanism. These are factory set and should
not require further adjustment.
4. Cams 2 and 3 may be adjusted to give the correct related burner firing rates on gas and oil.
5. The cam assembly can be rotated manually by disconnecting it from the drive motor using the
disengagement lever. The cams are adjusted with the special ‘C’ spanner provided.