Nortek AB 225 User manual

Doc No. 702115 Page of 24
AIRBLOC AB RANGE
GAS FIRED COMBINED FLUE AIR CURTAIN
INSTALLATION AND OPERATING MANUAL
INDEX Section
General Information -------------------------------------------------------- 1
Dimensions--------------------------------------------------------------------2
Technical Specifications ----------------------------------------------------3
Installation Details ----------------------------------------------------------4
Wiring Details ----------------------------------------------------------------5
Servicing ----------------------------------------------------------------------6
Commissioning --------------------------------------------------------------7
Parts Replacement ----------------------------------------------------------8
Spare Parts --------------------------------------------------------------------9
Fault Finding --------------------------------------------------------------- 10
User Instructions ----------------------------------------------------------- 11
Part No. 702115
Nortek Global HVAC (UK) Limited, Fens Pool Avenue, Brierley Hill, West Midlands, DY5 1QA
WARNINGS
Nortek Global HVAC (UK) Ltd equipment must be installed and maintained in accordance with
the relevant provisions of the Gas Safety (Installations and Use) Regulations 1998 for gas fired
products. Due account should also be taken of any obligations arising from the Health and Safe-
ty at Works Act 1974 or relevant codes of practice. In addition the installation must be carried
out in accordance with the current IEE wiring regulations (BS 7671), BS 6896 (Industrial & Com-
mercial) and any other relevant British Standards and Codes of Practice by a qualified installer.
All external wiring MUST comply with the current IEE wiring regulations.

Doc No. 702115 Page 2 of 24
1. General Information.
Welcome to the new AB Airbloc gas fired air
curtain models. Local regulations may vary in
the country of use and it is the installers
responsibility to ensure that such regulations are
satisfied.
All installation, assembly, commissioning and
service procedures must be carried out by
suitably qualified competent persons to the
statutory regulations in the country of use.
These instructions refer to products for use in
GB and the IE.
These air curtains are suitable for indoor use
only, and designed to operate at an ambient
temperature between –15°C and 30°C.
When installing, commissioning and servicing is
undertaken on the gas fired air curtains
specified in these instructions, due care and
attention is required to ensure that working at
height regulations are adhered to at the
mounting heights specified.
All dimensions shown are in mm unless
otherwise stated.
The manufacturer reserves the right to alter
specifications without prior notice.
PLEASE READ this document prior to
installation to familiarise yourself with the
components and tools you require at the
various stages.
The primary reason for installing gas fired air
curtains is to prevent the influx of cold outside
air through a door opening into a heated area.
Typical applications include large despatch bay
doors in factories and warehouses, and internal
doors between areas of different temperatures.
Wider door openings can be accommodated by
bolting two or more units together.
Air curtains control the internal climate by
emitting an air stream with enough velocity to
meet the floor so creating an air barrier in the
door area. To prevent the ingress of outside
draughts, the discharge louvre is angled
outwards, so that the air leaving the building
meets the wind trying to enter, thus deflecting it.
(See diagrams below).
Airbloc gas fired air curtains provide uniform air
distribution across the full width of the door,
keeping heated or conditioned air inside the
building and stopping the ingress of cold air,
draughts, and dust.
This manual provides detailed information on
the installation of Airbloc gas fired air curtains. It
is essential that these products are installed in
accordance with these manufacturers
instructions.
Without air curtain
With air curtain Pattern of airflow

Doc No. 702115 Page 3 of 24
2. Dimensions.
Module A
mm B mm C mm D mm E mm F mm G mm Weight (kg)
AB 175 1750 950 457 1090 700 125 1710 185
AB 225 2250 950 457 1090 700 125 2210 230
AB 400 4000 950 457 1090 700 125 N/A 415
Diagram 1: Dimensions (AB 400)
C
D
A A
B
E
F
G G
AB 175 module AB 225 module

Doc No. 702115 Page 4 of 24
3. Technical Specifications.
Air heater model ABxxxxCF
AB 225N AB 175N AB 225N AB 175N AB 225P AB 175P
Gas type Natural gas G20 (I2H) Natural gas G25 (I2L) Propane G31 (I3P)
Gas connection ½ ¨BSP external thread
Max supply pressure (mbar) 25 30 45
Min supply pressure (mbar) 17 20 25
Nominal pressure (mbar) 20 25 37
Gross heat input (kW) 66 49 66 49 65 49
Nett heat input (kW) 59.4 44.1 59.4 44.1 60.2 45.4
Gross heat output (kW) 60.1 44.6 60.1 44.6 59.2 44.6
Nett heat output (kW) 54.0 40.1 54.0 40.1 54.8 41.3
Gas flow rate (m³/hr) 6.3 4.7 7.4 5.4 - -
Gas flow rate (l/hr) - - - - 9.4 7.0
No. of injectors 5
Injector size (mm) Ø3.3 Ø2.9 Ø3.3 Ø2.9 Ø1.85 Ø1.65
Injector pressure (mbar) 7.5 7.0 10 10 25 25
Flue nominal bore (mm) 130
Air distribution fans
Type Centrifugal (with integral thermal trip)
Speeds 3
No. of fans 4 3 4 3 4 3
Maximum air volume 9600m3/hr (AB 175) 12800m3/hr (AB 225)
Voltage 230V 1PH 50Hz
Power rating (per fan) 1140 W
Current (per fan) 5.2A (FLC)
Start current (per fan) 12A
Model AB175 AB225
AB350= X 2
AB400= X 1 X 1
AB450= X 2
AB525= X 3
AB575= X 2 X 1
AB625= X 1 X 2
AB675= X 3
Constitution
WARNING:
THIS AIR CURTAIN SHOULD NOT BE
INSTALLED WHERE THERE IS A
CORROSIVE ATMOSPHERE.

Doc No. 702115 Page 5 of 24
Gap to be kept to a minimum
1.8m minimum
Bottom of air
heater to be
level with top of
door opening
4. Installation Details.
Health and Safety
Airbloc air heaters must be installed in
accordance with the relevant provisions of the
Gas Safety (Installations and Use) Regulations
1998. Due account should also be taken of any
obligations arising from the Health and Safety at
Work Act 1974 or relevant codes of practice. In
addition the installation must be carried out in
accordance with the current IEE wiring
regulations (BS 7671), BS 6896 (Industrial &
Commercial) and any other relevant British
Standards and Codes of Practice by a qualified
installer. Isolate all electrical supplies to the
heater & control panel before proceeding.
For your own safety we recommend the use of
personal protective equipment when handling
this air heater.
Before installation, check that the local
distribution conditions, nature of gas and
pressure, and the current state of adjustment of
the appliance are compatible.
Airbloc gas fired air heaters are supplied with
mounting brackets pre-fitted, either as single
units, or in multiples, which can be bolted
together to suit various door widths.
The minimum mounting height is 1.8 metres
(See diagram 2 below).
4.1.1
Each single air heater should be supported by
cantilever brackets (not supplied) then fixed
back to the building structure by bolting directly
using suitable support brackets, or by
suspending from above using suitable
steelwork. (See diagram 4, page 6).
4.1.2
Multiple air heaters should be bolted together
using 3 off M10 set pins, nuts and washers fitted
through the holes provided in the mounting
brackets, then suitable support channels (not
supplied) must be fixed on top of the factory
fitted brackets along the full length of the
assembled air heaters to spread the load.
The assembly can now be fixed back to the
building structure by bolting directly using
suitable support brackets, or suspending from
above using steelwork. (See diagram 3 page 6).
If required, the support channel may be
extended slightly past the ends of the air
heaters to aid fixing.
Note: Where multiple air heaters are fitted
above up and over doors or where central
support is inappropriate, the support
channel should be replaced with channels of a
greater cross section to prevent the assembly
from bending.
4.1 Mounting.
It may be necessary to adjust the position of the
air outlet louvres to provide the correct airflow
across the door opening. This can be done by
first loosening the four locking pins located two
at each end of the louvres (arrowed, Fig. A),
then loosening the intermediate locking Allen
pins (arrowed, Fig. B). The louvres can now be
moved to the desired position and the locking
pins re-tightened.
NOTE: The AB 225 model has two pairs of
intermediate locking Allen pins, whereas the
AB 175 model only has one pair.
Fig. B
Fig. A
Locking pins
Locking Allen pins
Diagram 2.

Doc No. 702115 Page 6 of 24
Model AB 225 AB 175
Gas type Natural gas (G20) Propane (G31) Natural gas (G20) Propane (G31)
Mass flow rate of
Flue gases (kg/s) 0.0340 0.0332 0.0242 0.0283
Flue gas temperature
@ flue outlet (ºC) 162 173 172.5 182
Flue pressure (Pa)
positive 55 49
Flue technical details.
4.2 Flueing.
The gas fired air heater must be installed with a
fixed flue as supplied by the manufacturer.
The flue pipe should be adequately supported at
regular intervals from the building structure and
terminated externally with a British Gas tested
and certified GC1 terminal.
The maximum flue length is 10m and the
maximum number of bends is four. The flue may
be installed vertically or horizontally. (See
diagrams 5, 6 and on page 7).
4. Installation Details cont.
4.3 Ventilation requirements.
In buildings having an air change rate of less
than 0.5 per hour, additional mechanical or nat-
ural ventilation is required. For detailed infor-
mation please see BS6230 section 5.2.2.2.1.1.
4.3.1 Mechanical ventilation.
Should be installed to meet a minimum of 0.5 air
changes per hour using appropriately sized fans
interlocked with the heaters.
4.3.2 Natural ventilation.
Low level ventilation openings with a free area
of at least 2cm2/kW shall be provided. See
BS6230 section 5.2.2.2.1.2.
Typical support channels PLAN VIEW
Cantilever brackets
(not supplied)
Factory fitted
mounting brackets
FRONT VIEW
Diagram 3: Support channel Support points
Diagram 4: Mounting

Doc No. 702115 Page 7 of 24
Diagram 5: Typical vertical flue arrangement
FRONT VIEW
600mm
minimum
GC1
Terminal
4. Installation Details cont.
Ventilation requirements are detailed in
section 4.3.
Diagram 6: Typical horizontal flue arrange-
SIDE VIEW
GC1 terminal
Maximum flue length = 10m + 4 bends
Alternative flue exit
Flue damper
Flue damper
Note:
When the horizontal flue is to pass through a wall constructed of combustible material, a suitable
approved fireproof sleeve should be fitted prior to installing the flue pipe.

Doc No. 702115 Page 8 of 24
5. Wiring Details.
In addition to the above burner wiring diagram, a customer specific control
panel wiring diagram will be supplied with each air heater.
Diagram 7: Burner control wiring
WARNING:
THIS HEATER SHOULD NOT BE
INSTALLED WHERE THERE IS A
CORROSIVE ATMOSPHERE.

Doc No. 702115 Page 9 of 24
5. Wiring Details cont.
5.1 Burner controls
The burner controls are mounted in the burner
control cubicle which is an integral part of the air
curtain casing and are accessible by opening a
hinged lid on the right hand side of the air
curtain (see Figs. 4 and 5 in section 8 of this
manual for details). The controls accessible in
the cubicle are: gas solenoid valve, ignition
controller, air pressure switch, flame probe,
ignition electrode, reset switch, red and amber
neon lamps, plus associated wiring harness. For
details see burner wiring diagram in section 5,
page 9.
5.2 Control panel.
The electrical control panel incorporates the
facility to interlock with the door opening
mechanism and automatically switch the air
curtain between high/low speed as the door is
opened and closed. A pair of volt free auxiliary
contacts are required on the door open/close
contactor which closes as the door opens. If this
is not available then a suitably positioned limit
switch and striker plate will need to be fitted to
the door.
The panel incorporates an auto/off/manual
selector switch, which, when in 'auto' mode
operates the air curtain in low speed via an
external room thermostat provided the door is
the down position. In the door up position the air
curtain operates in high speed and overrides the
room thermostat The 'manual' position overrides
the door interlock and thermostat, and the 'off '
position turns the air curtain off.
A cool/heat selector switch is also incorporated
which allows the air curtain to supply heated
air, or unheated ambient air.
The panel also contains a removable link on the
main terminal rail to allow the air curtain to be
switched on and off remotely via a BMS control
relay.
The panel may also be fitted with optional low
voltage (24V AC) relays for fire alarm/door
contact interlocks.
Regardless of the position of any of the above
switches, the main air fans must be running to
allow the burner to run.
5.3 Overheat protection.
In the event of any overheat condition there are
two thermal limit controls fitted inside the air
curtain. The controls are factory set and
non-adjustable. The self resetting (cycling)
control activates at 70ºC, and the manual reset
control at 96ºC. If either set point is reached, the
corresponding limit control will interrupt the
electrical power to the burner gas valve. The
burner will not relight until the limit control has
reset. The manual reset button is located on top
of the heater on the left hand side of the
thermostat cover and can be accessed after first
removing the dust cover. (See Figs. C and D).
These safety devices provide protection in the
event of an air distribution fan motor failure, or
lack of airflow due to restrictions. (For location
see section 8 Fig.29, and section 5 diagram 8,
burner controls wiring diagram).
Warning: never attempt to bypass the
thermal limit controls as hazardous
conditions could result.
Fig. C Fig. D
A customer specific control panel wiring
diagram will be supplied with each air curtain

Doc No. 702115 Page 10 of 24
6. Servicing.
These appliances should be serviced annually by a competent person to ensure safe
and efficient operation. In exceptionally dusty or polluted conditions more frequent
servicing may be required. The manufacturer offers a maintenance service. Details
available on request. Isolate gas and electricity supplies before commencing any work.
Cross point
screwdriver
6.1 Tools Required.
The following tools and equipment are advisable
to complete the tasks laid out in this manual.
Suitable alternative tools may be used.
Small flat head
screwdriver
Allen key set Adjustable
pipe wrench
Adjustable
spanner
10mm spanner
13mm spanner
Manometer Soft
brush
6.2 Burner assembly.
The major components of the burner assembly
can be accessed by removing the two lid
retaining screws located on the right hand side
on top of the air heater, and swinging the lid
downwards as shown in Figs 4 & 5 in section 8
of this manual. Section 8 also details the
removal of the major components.
6.2.1 Manifold/injectors.
Remove the manifold complete with injectors as
described in section 8. The manifold/injectors
should be examined for signs of debris and
cleaned if necessary by blowing compressed air
in the reverse direction to flow. Individual
injectors can be replaced if necessary.
6.2.2 Burners.
Access to the burners is achieved by first
removing the mounting plate carrying the
ignition sequence controller and pressure
switch, (see section 8). The access plate can
now be removed after unscrewing the four fixing
screws. The burners can now be examined and
cleaned using a soft brush, or by blowing
compressed air in the reverse direction to flow.
Individual burners can be replaced if necessary
by removing the two retaining screws.
6.2.3 Spark electrode .
Remove the spark electrode as described in
section 8 and examine. If it is in good order
check the electrode gap, this should be 3.5mm ±
0.5mm. Adjust the gap if necessary by carefully
bending the earth rod, then re-checking the
measurement.
6.2.4 Flame probe.
Remove the flame probe as described in section
8 and examine for signs of erosion. The probe
should be cleaned if necessary using a fine
grade emery paper.
6.3 Emitter tubes.
6.3.1 External.
Brush away any dust on the exterior of the
emitter tubes after first removing the ten screws
retaining the mesh air inlet grille as shown in
Fig.0. overleaf
6.3.2 Internal.
To gain access first remove the five retaining
screws from the inspection cover as shown in
Fig.1 overleaf.