Nu-Way MGN800-LN M3D Instruction Manual

Installation & Maintenance Manual
MGN 800 –LN SC Modulating
Gas Burner
Tel:[phone] Fax: [phone] Email: [e-mail] Web: www.nu-way.co.uk

2
E. 13.11.06 • G. 21.09.11
Contents
1 General information ................................................................................................................... 3
2 Checking scope of delivery and electrical data .......................................................................... 3
3 Maintenance and customer service ........................................................................................... 3
4 Operating instructions ................................................................................................................ 3
5 Instruction of operating personnel.............................................................................................. 3
6 Filter/Strainer .............................................................................................................................. 3
7 Key for code designation ........................................................................................................... 4
8 Technical specifications .............................................................................................................. 4
9 Boiler connection dimensions .................................................................................................... 4
10 Mounting the gas jacket on the boiler ......................................................................................... 5
11 Mounting the burner housing on the gas jacket (service position) .............................................. 5
12 Electrical connection .................................................................................................................. 5
13 Air flap positioning motor .......................................................................................................... 7
14 Air pressure switch ..................................................................................................................... 7
15 Gas pressure switch for gas inlet pressure ................................................................................. 7
16 Gas pressure switch for VPS ...................................................................................................... 7
17 Adjustment of the ignition electrodes ......................................................................................... 8
18 Flame control with Ionisation monitor.......................................................................................... 8
19 Adjustment of the burner head.................................................................................................... 8
20 Control unit MPA 22.................................................................................................................... 9
21 MPA 22 control unit display ....................................................................................................... 9
22 Start-up ....................................................................................................................................... 9
23 Gas train KEV
II
1 ½" , KEV 2" and KEV DN65......................................................................... 10
23a Gas train KEV25 1", KEV30 1½", KEV45 2" and KEV45 DN 65............................................... 11
24 Adjustment mode - pneumatic gas-fired operation ................................................................... 12
25 Calculation principles for gas burner adjustment ..................................................................... 14
26 Adjustment tables ..................................................................................................................... 15
27 Troubleshooting / process description ...................................................................................... 16
28 Adjustments log ........................................................................................................................ 20
29 Overall dimensions .................................................................................................................. 22
30 Working ranges ......................................................................................................................... 22

3
E. 13.11.06 • G. 21.09.11
1 General information
Installation of a gas-fired heating system must be performed in accordance with the applicable regulations
and guidelines. It is, therefore, the duty of the installation engineer to ensure that all regulations have been
read carefully and understood. Installation, start-up and maintenance must be performed with utmost care.
The burner must not be operated in rooms with high levels of air humidity (laundry rooms), dust or corrosive
vapours. The boiler room must be ventilated accordingly with ventilation air.
Nu-Way MGN800-LN M3D Series gas burners are suitable for combustion of natural gas or liquid gas in
accordance with EN 437 and are in compliance with the EN 676 European standard.
2 Checking scope of delivery and electrical data
Before installing the Nu-Way gas burner, please check that all items included in the scope of delivery are
present.
Scope of delivery:
burner housing, gas jacket with burner pipe, mounting kit, documentation and gas train.
Gas installation and commissioning are subject to the applicable national regulations. The gas pipe must
be designed to conform to the flow rate and the available gas flow pressure and routed with the lowest pres-
sure loss over the shortest distance to the burner.
The loss of gas pressure via the gas train and the burner and the resistance on the fuel gas side of the heat
generator must be less than the connection flow pressure.
Caution !
Observe sequence and throughflow direction of valves and fittings.
3 Maintenance and customer service
The complete system should be checked once a year for correct functioning and leaks by a representative
of the manufacturer or other suitably qualified person.
We accept no liability for consequential damage in cases of incorrect installation or repair, the fitting of non-
genuine parts or where the equipment has been used for purposes for which it was not intended.
4 Operating instructions
The operating instructions together with this technical information leaflet must be displayed in a clearly vi-
sible position in the boiler room. The address of the nearest customer service centre must be displayed on
the back of the operating instructions.
5 Instruction of operating personnel
Faults are often caused by operator error. The operating personnel must be properly instructed in how the
burner works. In the event of recurring faults, Customer Service should be notified.
6 Filter/Strainer
According EN676 a filter/strainer shall be fitted at the inlet of the safety shut-off valve to prevent the ingress
of foreign elements.

4
E. 13.11.06 • G. 21.09.11
7 Key for code designation
8 Technical specifications
9 Boiler connection dimensions
Burner type
Technical specifications MGN800-LN M3D
Burner output in kW 225 - 860
Gas type Natural gas LL + E = "N"
Mode of operation Progressive two-stage or modulating
Voltage 3 / PE ~50 Hz 400 V
Max. power consumption at start / during operation 6.5 A max./ 3.6 A eff.
Electric motor power (at 2800rpm) in kW 1.0
Flame failure controller Ionisation
Control box MPA 22
Weight in kg 56
Noise emission in db(A) £ 78
MGN800-LN
LowNox
Burner output max.
Natural gas LL + E ="N"
Series
All dimensions are given in mm
220
250-290
M10
45°
45°

5
E. 13.11.06 • G. 21.09.11
10 Mounting the gas jacket on the boiler
Use adhesive to affix the gas-jacket gasket to the
gas jacket.
The boiler connection plate has to be prepared in ac-
cordance with the sizes as stated in „9. Boiler connec-
tion dimensions“. You can use the gas-jacket gasket as
a template.
Using an 8 mm socket-head wrench, secure the gas
jacket to the boiler with the 4 M 10 fastening screws
and washers. The air pressure connection for the gas
train must be positioned at the top.
11 Mounting the burner housing on the gas jacket (service position)
Position the burner housing in the gas-jacket hinge
and secure it with a rod. The burner is now in the ser-
vice position.
Make sure that the gasket is correctly seated
between the gas jacket and the burner housing.
Swing the burner closed and insert the second secu-
ring rod into the hinge. Tighten the screw at the top to
secure the burner in position.
12 Electrical connection
Always set the main switch to "Off" and remove
the fuse before connecting the cables or removing
electrical components.
The burner must be connected to the electricity supply
in accordance with the wiring diagram. This wok must
be performed by trained, qualified electricians. The
supply cable to the burner must be of the flexible type.
Air pressure connection
B

6
E. 13.11.06 • G. 21.09.11
See Circuit diagram
The cover has to be removed and set to the service po-
sition in order to permit access to the control unit. Re-
move the securing screws (1) and fold the cover down
to the left.
Two-stage or modulating operation
IMPORTANT !
The coding plug X85 with jack X86 must be connected
during two-stage operation (as-delivered condition, see
Fig.).
For modulating operation, the coding plug X85 must be
removed.
Once the connection to the electricity supply has been
established, check the wiring and briefly actuate the
motor contactor with an electrician's insulated
screwdriver to check the direction of rotation of the bur-
ner motor.
IMPORTANT !
The motor protective relay is set ex-works. The set va-
lue should not be incorrectly adjusted.
Cover
1
1
Coding plug

7
E. 13.11.06 • G. 21.09.11
13 Air flap positioning motor
The air flap positioning motor is designed for air flap adju-
stment on progressive two-stage burners or modulating
burners. The motor is activated electronically via the
microprocessor-controlled control box.
Do not open the air flap positioning motor. The optics
can become damaged irreparably. No warranty will be
given if the seal is broken.
14 Air pressure switch
The air pressure switch is a differential pressure switch
and monitors pressure at the forced-air burner.
The air pressure switch is preset at the factory.
15 Gas pressure switch for gas inlet pressure
The gas pressure switch on the gas train serves to monitor the gas inlet pressure. The burner is shut down
if the gas inlet pressure drops below the set minimum value (preset at factory). The burner starts up auto-
matically again when the minimum pressure is exceeded.
16 Gas pressure switch for VPS
The gas pressure switch for VPS is preset to 10 mbar at the factory.
The operating point of the gas pressure switch for VPS must be set to half the inlet flow
pressure.

8
E. 13.11.06 • G. 21.09.11
17 Adjustment of the ignition electrodes
The ignition electrodes are preset at the factory.
18 Flame control with Ionisation monitor
In the presence of an alternating-current voltage between burner and ionisation rod, the rectifying effect of
the flame causes a direct current to flow. This ionisation current is the flame signal and is amplified before
being output to the control box. A flame cannot be simulated, because the rectifying effect collapses if there
is a short-circuit between sensor electrode and burner.
Measuring ionisation current
The ionisation current must be measured during burner start-up and maintenance or after a fault indication
in the control box. Disconnect the plug of the ionisation cable and connect the ionisation
measuring cable.
Perform measurement straight after the post-ignition time during the safety time period !
The ionisation current must be at least 1.5 µA. Currents lower than 1.5 µA cause unstable operation or shut-
down. If the current is too low clean the ionisation rod and the inside of the burner tube. It may be necessary
to correct the shape of the ionisation rod. If the ionisation rod is defective, replace the electrode. Reverse
the polarity of the ignition transformer, if necessary. Check the cables for moisture formation and dry if ne-
cessary.
19 Adjustment of the burner head
Set the position of the burner head according to bur-
ner output in accordance with the table on page 16ff.
2,5 - 3 mm
MG1/MG2-LN
3-4
(80)
2
Abstand
Keramikkörper
Keramikkörper
Zündelektrodenhalter
Stauscheibe
Richtrohr

9
E. 13.11.06 • G. 21.09.11
20 Control unit MPA 22
The MPA 22 is a microprocessor-controlled intermittent-
duty control box for controlling and monitoring pneumatic
modulating forced-air burners with an actuator drive. For
operation as an automatic gas burner control with integral
valve proving system.
The MPA 22 has e-BUS connectivity.
21 MPA 22 control unit display
22 Start-up
The burner can be put into operation once the gas and electrical installation and assembly work has been
completed.
• Check the connections on the gas train.
• Prepare the flue-gas analyser.
• Start the burner.
• Adjustment of air surplus and output. See 23. Gas burner with gas train
KEV
II
1 ½" , KEV 2" and KEV DN65 or 23.a Gas train KEV25 1" and KEV30 1 ½ ".
• Record the setting data.
• Check the gas pressure monitor after start-up. To do so, close ball valve slowly. The burner must shut
down, but must not go into fault mode. If the burner goes into fault mode, increase the setting on the
gas pressure monitor.
Enter or Reset key Key 1
Activation of gas valve
in combination
with +/- key
Key 2
Activation of air valve
in combination
with +/- key
Key + / Key -
Start-up comes on
during start-up, off when
burner is in operation
comes on when
is active
information mode
comes on when
adjustment mode
is active
comes on when
gas flap is active
symbol for
opening /
closing flaps
comes on when
air flap
is active
Visual
LC h = service hours indicator
l, m
3
= oil or gas consumption
comes on when service mode
is active
Fault
Operation, flame present

10
E. 13.11.06 • G. 21.09.11
23 Gas train KEV
II
1 ½" , KEV 2" and KEV DN65
Screw each air pressure measuring nipple into the top of the gas jacket (see 10. Mounting the gas jacket
on the boiler).
Connect the blue hose to the "AIR" connection on the gas train and the air pressure connection on the gas
jacket. The blue hose serves as a control line for the gas train and must be routed in a loose loop without
kinking.
Remove the plate for covering the adjustment screws from the gas pressure regulator.
Start the burner.
1. Setting the air surplus in high and low-load operation
• Set the air flap positions P9 for high-load operation and P1 for low-load operation as specified in
26. Adjustment tables. Follow the setting procedure described in 24. Adjustment mode - pneumatic
gas-fired operation with MPA 22 display.
• In high-load operation, set the air surplus with the "large flame" adjustment screw on the gas pressure
regulator. The CO
2
level in the flue gas should be 9-10% for natural gas.
• In low-load operation, set the air surplus with the "small flame" adjustment screw on the gas pressure
regulator. The CO
2
level in the flue gas should be 9-10% for natural gas. The low-load setting influ-
ences the high-load setting.
• In high-load operation, check the air surplus and, if necessary, correct the setting with the "large
flame" adjustment screw on the gas pressure regulator.
2. Setting the output in high and low-load operation
• Check the high-load setting via the gas flow at the gas meter or compare the nozzle pressure with the
values stated in 26. Adjustment tables. The output can be increased by opening the air flap (to
increase P9) and reduced by closing the air flap (to reduce P9). The air surplus is not affected by this
adjustment.
• Check the low-load setting via the gas flow at the gas meter or compare the nozzle pressure with the
values stated in 26. Adjustment tables. The output can be increased by opening the air flap (increase
P1) and reduced by closing the air flap (reduce P1). The air surplus is not affected by this adjustment.
Installing the gas train
Installation position only in horizontal line, not tilted.
Minimum distance to walling 20 mm
Screw the combustion chamber pressure measuring nipple into the gas jacket at the top (see "10 Mounting the gas jacket on
the boiler").
Route the connecting hose between the measuring nipple for combustion chamber pressure and the gas train in a loose loop.
Gas pressure switch
SKP 15
VGD
Pulse line p
G
SKP 75
Cover plate for
"AIR" air pressure connection
(gas inlet pressure)
Adjustment screws
Gas pressure switch
for leak check
Pressure gauge
Nozzle pressure p
G
detail