Giersch MG20-ZM-L-LN Series User manual

Issued in June 2020
Subject to tech. modifications
to improve the product!
Gas
Technical Information • Installation Instructions
MG20-ZM-L-LN
GB

2/32 03.06.20, Subject to alterations
Contents
1 General information ................................................................................................................... 3
2 Checking the scope of delivery and electrical ratings ................................................................ 3
3 Maintenance and customer service ........................................................................................... 4
4 Operating instructions ................................................................................................................ 4
5 Instruction of operating personnel.............................................................................................. 4
6 Key for code designation ........................................................................................................... 4
7 Technical specifications .............................................................................................................. 5
8 Boiler connection dimensions .................................................................................................... 5
9 Mounting the gas jacket mantel at the boiler .............................................................................. 5
10 Mounting the burner housing on the gas jacket (service position) ............................................. 6
11 Terminal diagram connector pin assignments ............................................................................ 7
12 Electrical connection ................................................................................................................... 8
13 Air flap positioning motor .......................................................................................................... 9
14 Air pressure switch ..................................................................................................................... 9
15 Gas pressure monitor ............................................................................................................... 10
16 Adjusting the ignition electrode ................................................................................................. 11
17 Measuring the ionisations current ............................................................................................. 11
18 Adjusting the mixer head ......................................................................................................... 12
19 Connection diagram LMV27 ..................................................................................................... 12
20 Operating instructions and equipment description LMV............................................................ 13
21 Start-up and calibration ............................................................................................................ 14
22 Gas burner with gas train KEV
II
1 ½", KEV 2", KEV412 1 1/2“, KEV300 1“, KEV DN65 ........... 20
23 Calculation principles for gas burner adjustment .................................................................... 22
24 Adjustment tables .................................................................................................................... 23
25 Error code list LMV .................................................................................................................. 25
26 Adjustments log ........................................................................................................................ 27
27 Exploded view / spare parts list................................................................................................. 28
28 Declaration of Conformity for Gas Burners ............................................................................... 30
29 Overall dimensions .................................................................................................................. 32
30 Working ranges........................................................................................................................ 32

Subject to alterations, 03.06.20 3/32
General information
1 General information
Installation of a gas-fired heating system must be
performed in accordance with the applicable regula-
tions and guidelines. It is therefore the duty of the in-
staller to be fully familiar with all regulations.
Installation, start-up and maintenance must be per-
formed with utmost care.
The burner must not be operated in rooms with high
levels of air humidity (laundry rooms), dust or corro-
sive vapours. The boiler room must be ventilated ac-
cordingly with ventilation air.
Giersch MG Series gas burners are suitable for
combustion of natural gas in accordance with
DIN EN 437 and are in compliance with the
DIN EN 676 European standard.
2 Checking scope of supply and
electrical ratings
Before installing the gas burner, please check the
scope of delivery.
Scope of delivery:
burner housing, gas jacket with burner pipe, mount-
ing kit, documentation and gas train.
Gas installation and commissioning are subject to
the applicable national regulations, e.g. in Germany
the Technical Regulations of the DVGW (DVGW-TR-
GI).
The following must be observed for Switzerland:
SVGW Gas Provisions G1, G3: Gas installation
EKAS Form.
1942: Liquefied gas regulation, Part 2 Regulations
of cantonal authorities (e. g. fire department regula-
tions).
The gas pipe must be designed to conform to the
flow rate and the available gas flow pressure and
routed with the lowest pressure loss over the short-
est distance to the burner.
The loss of gas pressure via the gas train and the
burner as well as the resistance on the fuel gas side
of the heat generator must be less than the connec-
tion flow pressure.
Caution !
Observe sequence and through-flow direction
of valves and fittings.

4/32 03.06.20, Subject to alterations
Maintenance and customer service
3 Maintenance and customer service
The complete system should be checked once a
year for proper functioning and leak tightness by an
authorised representative of the manufacturer or by
another expert.
Only qualified personnel may open only for mainte-
nance, not during on-going operation. Prior to open-
ing/swinging out, de-energise the burner and let it
cool down. After completion of work, close the burn-
er again.
Wear protective clothing|/hearing protection when
working in the boiler house
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 intend-
ed.
4 Operating instructions
The operating instructions together with this techni-
cal information leaflet must be displayed in a clearly
visible position in the boiler room. The address of
the nearest customer service centre must be dis-
played on the back of the operating instructions.
5 Instruction of operating personnel
Failures are often caused by operator error. The op-
erating personnel must be properly instructed in
how the burner works. In the event of recurring
faults, Customer Service should be notified.
6 Key for code designation
MG 20/1-ZM-L-N-LN
LowNox
Erdgas E+LL="-N" oder Flüssiggas="-F"
Luftabschlussklappe
zweistufig gleitend / modulierend
Brennertyp / Leistungsgröße
Brennerserie
LowNox
Natural gas LL + E = "N", Liquid gas 3B/P = “F“
Size
Series
Air shut-off flap
Two-stage / modulating

Subject to alterations, 03.06.20 5/32
Technical specifications
7 Technical specifications
8 Boiler connection dimensions
Dimensions in mm
9 Mounting the gas jacket on the
boiler
The boiler connection plate must be prepared ac-
cording to the dimensions specified for the boiler
connection dimensions. You can use the gas-jacket
gasket as a template.
Screw the gas jacket to the boiler using the four
M10 fastening screws with washers and a size Allen
key. The air pressure switch for the gas train must be
at the top.
Burner type
Technical specifications MG20/1-ZM-L-LN MG20/2-ZM-L-LN
Burner output in kW 224 - 860 247 - 1350
Gas type Natural gas LL + E= "N", liquid gas 3B/P = "F"
Mode of operation Progressive two-stage or modulating
Voltage 3 / PE ~50 Hz 400 V / T16 A
Max. power consumption at start / during oper-
ation
6.5 A max./ 3.6 A eff. 8.0 A max./ 4.6 A eff.
Electric motor power (at 2800rpm) in kW 1.1 2.2
Flame control Ionisation
Burner management system LMV27
Weight in kg 56 58
Noise emission in db(A)
≤ 78 ≤ 78
Gas burner class 3
NOx limit
≤ 80 mg/kWh
220
250-290
M10
45°
45°
Air pressure connection

6/32 03.06.20, Subject to alterations
Mounting the burner housing on the gas jacket (service position)
10 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
service position.
Attach the ignition and ionisation cable to the igni-
tion and ionisation electrodes.
Carefully swing the burner closed.
Do not pinch electrical cables.
Insert the second mounting rod into the hinge. Tight-
en the screw at the top to secure the burner in posi-
tion.

Subject to alterations, 03.06.20 7/32
Terminal diagram - connector pin assignments
11 Terminal diagram - connector pin
assignments
If the male connector has already been wired:
check the connections according to the
connection diagram!
The electrical connection of the burner must be
made in the male connector included according to
the connection diagram, taking account of the local
regulations.
The supply cable must be fused with max. 10 A fast
blow or 6.3 A slow blow and must be routed using
flexible cable.
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Boiler customer
Connection
boiler in
two stages
Modulating
boiler
connection
main switch
external fuse
safety
temperature
limiter
Thermostat
heat request
Failure
lamp
Power light
external fuse
Extract wiring diagram page 2
Extract wiring diagram page 7

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Electrical connection
12 Electrical connection
De-energise the burner when carrying out
connection work and removing electrical parts!
The burner must be connected to the electricity sup-
ply in accordance with the wiring diagram. This work
must be performed by trained, qualified electricians.
The supply cable to the burner must be of the flexi-
ble type.
To access the firing unit, the cover must be brought
to the service position. To do this, remove the secur-
ing screws (1) and fold the cover down to the left.
After wiring has been completed, check the direc-
tion of rotation of the burner motor by actuating the
motor contactor with an insulated screwdriver.
The direction of rotation is correct when the fan
wheel turns towards the boiler (also see arrow on
the motor flange).
IMPORTANT !
The motor protection relay is set at the factory. The
set value should not be modified.
B
Cover
1
1

Subject to alterations, 03.06.20 9/32
Air flap positioning motor
13 Air flap positioning motor
The air flap positioning motor is designed for air flap
adjustment on progressive two-stage burners or
modulating burners. The motor is activated electron-
ically via the microprocessor-controlled control box.
Do not open the air flap actuator while it is under
voltage. The internal optics would be destroyed.
No warranty if the seal is broken!
14 Air pressure monitor
The air pressure switch is a differential pressure
switch and monitors the air pressure at the forced-
air burner.
The air pressure switch is pre-set at the factory.

10/32 03.06.20, Subject to alterations
Gas pressure monitor
15 Gas pressure monitor
15.1 Gas pressure switch min.
The gas pressure switch MIN at the gas fitting ser-
ves to monitor the gas inlet pressure. If the minimum
gas inlet pressure is not reached (factory setting), the
burner is switched off. The burner automatically
starts again when the minimum pressure is excee-
ded. The gas pressure monitor as density control
DK generally serves to check the valves and must be
set to 50% of the static gas inlet pressure.
The monitoring of the gas inlet pressure and the
tightness control are either carried out only with the
gas pressure monitor DK (the jumper GDW MIN
must not be removed) or with the gas pressure
switch MIN and the gas pressure switch DK (the
GDW MIN jumper has to be replaced with the
connection of the gas pressure switch MIN).
When using the gas cycle MB-VEF 412, the connec-
tion is made via the 7-pin connector and is only
evaluated as DK MIN. The plug bridge must not be
removed
Additional parameterization of the LMV is not re-
quired here.
15.2 Gas pressure monitor max.
Optionally a gas pressure switch max. can be incorporated.
The LMV and the wiring have been prepared such that only the jumper in the socket part (brown) at the
burner needs to be removed. In addition, the male connector and the gas pressure switch max. must be
wired in accordance with the circuit diagram. If the gas pressure switch max. has tripped, a fault is shown
in the display (AZL).
First, the gas pressure switch max. must be unlocked; to do this the lid of the gas pressure switch max.
must be unscrewed and the red button pressed.
Then, the fault in the display can be deleted (press the i/reset button for 3 sec.).