Instruction Manual.
GAS FIRED AIR CURTAIN
AB 175, AB 225
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
WARNINGS
1 This appliance must only be installed by a competent person in accordance with
the requirements of the Codes of Practice or the rules in force.
2 All external wiring MUST comply with the current IEE wiring regulations.
3 Warning this appliance must be earthed.
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.
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.
The manufacturer reserves the right to alter
specifications without prior notice.
Without air curtain
With air curtain
Pattern of airflow
2
2. Dimensions.
Diagram 1: Dimensions
Model
C
B
mm
C
mm
D
mm
E
mm
F
mm
AB 175 1750 950
457
700
700
125 1710
185
AB 225 2250 950
457
700
700
125 2210
230
R/H VIEW
D
A
mm
F
E
3
PLAN VIEW
A
G
FRONT VIEW
B
G
mm
Weight
(kg)
3. Technical Specifications.
AB 175N
Air curtain model
AB 225N AB 175N
Natural gas G20 (I2H)
Natural gas G25 (I2L)
AB 225N
Gas type
AB 225P
AB 175P
Propane G31 (I3P)
½ ¨ BSP external thread
Gas connection
Max supply pressure (mbar)
25
30
45
Min supply pressure (mbar)
17
20
25
Nominal pressure (mbar)
20
25
37
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
-
-
-
-
-
-
9.4
7.0
Gross heat input (kW)
Gas flow rate (l/hr)
5
No. of injectors
Injector size (mm)
Injector pressure (mbar)
Ø3.3
Ø2.9
Ø3.3
Ø2.9
Ø1.85
Ø1.65
7.5
7.0
10
10
25
25
130
Flue nominal bore (mm)
I/D fan
Type (AmbiRad part No.)
AACO (200421)
Voltage
230V 1 Ph 50 Hz
100W
Power rating
0.5A (FLC)
Current
Air distribution fans
Centrifugal (with integral thermal trip)
Type
3
Speeds
No. of fans
4
3
4
3
3
3
3
7068m /hr (AB 175)
Maximum air volume
4
9425m /hr (AB 225)
230V 1PH 50Hz
Voltage
550 W
Power rating (per fan)
4.5A (FLC)
Current (per fan)
11.25A
Start current (per fan)
Electrical power
Total electrical power
consumption
2.3kW
1.75kW
2.3kW
1.75kW
2.3kW
1.75kW
Constitution
Model
AB175
AB350=
X2
AB400=
X1
AB450=
4
AB225
X1
X2
AB525=
X3
AB575=
X2
X1
AB625=
X1
X2
AB675=
X3
4. Installation Details.
Health and Safety
Airbloc air curtains 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 7671:2008), BS 6896:2005
(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 curtain.
4.1.1
Each single air curtain 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 3, page 6).
4.1.2
Multiple air curtains 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 curtains 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 4 page 6).
If required, the support channel may be
extended slightly past the ends of the air
curtains to aid fixing.
Before installation, check that the local
distribution conditions, nature of gas and
pressure, and the current state of adjustment of
the appliance are compatible.
Note: Where multiple air curtains 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.
Airbloc gas fired air curtains 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).
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.
4.1 Mounting.
Diagram 2.
Gap to be kept to a minimum
Fig. A
Bottom of air
curtain to be
level with top of
door opening
Locking pins
Fig. B
1.8m minimum
Locking Allen pins
5
4. Installation Details cont.
Diagram 3: Mounting method (single air curtain)
Cantilever brackets
(not supplied)
Factory fitted
mounting brackets
FRONT VIEW (SINGLE AIR CURTAIN)
Diagram 4: Support channel (multiple air curtains)
Support points
Air curtain 1
Air curtain 2
Factory fitted brackets
PLAN VIEW (TWIN AIR CURTAINS)
Typical support channels
4.3 Ventilation requirements.
In buildings having an air change rate of less
than 0.5 per hour, additional mechanical or
natural ventilation is required. For detailed
information please see BS6230:2005 section
5.2.2.2.1.1.
4.2 Flueing.
The gas fired air curtain must be installed with a
fixed flue. The fan is fitted with a 130mm
diameter female aluminium outlet. (Flue and
fittings can be 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 7m and the
maximum number of bends is two on
individually flued appliances. The flue may be
installed vertically or horizontally, noting that
horizontal flues MUST be terminated vertically.
(See diagrams 5, 6 and 7 on pages 8 and 9).
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
section 5.2.2.2.1.2.
6
4. Installation Details cont.
Flue technical details.
Model
Gas type
AB 225
AB 175
Natural gas (G20)
Propane (G31)
Natural gas (G20)
Propane (G31)
0.0340
0.0332
0.0242
0.0283
162
173
172.5
182
Mass flow rate of
Flue gases (kg/s)
Flue gas temperature
@ flue outlet (ºC)
Flue pressure (Pa)
positive
55
49
Method for calculating equivalent flue resistance.
Component
Internal size (mm)
Resistance factor (Ke)
Pipe
130
0.25
per metre
90º bend
130
0.5
per fitting
135º bend
130
0.25
per fitting
130 GC1
0.25
per fitting
Terminal
Inlet resistance of flue (Ki)
Outlet resistance of flue (Ko)
130 mm spigot
130 mm flue
1.0
1.0
The formula for calculating the equivalent flue
size is as follows:
He = Ha x
Example (125mm diameter):
(Ki + Ko)e
(Ki + Ko)a - KeHa + ΣK
Where:
He is the height of the equivalent flue.
Ha is the vertical height of the actual or
proposed flue measured from the flue spigot.
Ki is the inlet resistance of the flue.
Ko is the outlet resistance of the flue.
Subscript 'e' refers to the equivalent flue
diameter. Subscript 'a' refers to the actual or
proposed flue diameter.
Ke is the resistance per unit length of the
equivalent flue.
ΣK is the resistance (other than the inlet and
outlet resistances) of the actual or proposed
flue.
Note: Ki and Ko are obtained from the table
above.
7
Inlet resistance of actual flue
1
Outlet resistance of actual flue
1
Inlet resistance of equivalent flue
1
Outlet resistance of equivalent flue
The vertical height of the actual or
proposed flue measured from the
flue spigot
Other resistances of actual flue:
1
7
Terminal (1)
0.25
90º bend (0)
0
135º bend (0)
0
Flue pipe
1.75
He =
6.22
4. Installation Details cont.
Diagram 5: Typical vertical flue arrangement
GC1 terminal
600mm
minimum
7.0m max
1m min
Fan to flue adapter
(supplied)
FRONT VIEW
Diagram 6: Typical horizontal flue arrangement
(Method 1, rear exit)
GC1 terminal
I/D fan rotated
through 90º
Fan to flue adapter
(supplied)
600mm
minimum
SIDE VIEW
Ventilation requirements are detailed in
section 4.3.
8
4. Installation Details cont.
Diagram 7: Typical horizontal flue arrangement
(Method 2, left or right hand exit)
PLAN VIEW
Alternative position
for 90 deg. bend
90 deg. bend
(not supplied)
Fan to flue
adapter (supplied)
Flue passes through
mounting bracket(s)
GC1 terminal
9
4. Installation Details cont.
Before fitting a horizontal flue, it will be
necessary to rotate the I/D fan through 90º on
it`s mounting bracket to enable the flue to be
routed to the rear of the air curtain as shown in
diagram 6.
Removal and refitting of the I/D fan is described
in section 8 of this manual, parts replacement
(Fig.18).
Note:1:The maximum permissible
horizontal flue length should be calculated
using the formula for equivalent flue sizes
shown on the previous page.
2: 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.
5. Wiring Details.
Diagram 7: Burner control wiring
L
FAN
VACUUM SWITCH
BROWN
N
BLUE
N.C.
GREEN/YELLOW
C.
N.O.
GREEN/YELLOW
SOLENOID VALVE
R/H
5 PIN SOCKET
GREEN/YELLOW
MAINS INPUT/ LOCKOUT
BLUE
BLUE
L/O + RESET
SWITCH
YELLOW
RED
OVERHEATS
GREEN/YELLOW
BROWN
WHITE
6
4
3
5
TO FLAME SENSOR
BLUE
BLUE
BROWN
GREY
L2
BLUE
MAINS
ON
LAMP
YELLOW
L/O L/O
IND RES
L1
BURNER
ON
LAMP
BLACK
N
L3
CON 4
BROWN
BROWN
C5-7
BLUE
C5-6
C5-5
C5-4
C5-3
C5-2
C5-1
C1-3
C1-2
C1-1
C4-5
C4-4
C4-3
C4-2
C4-1
YELLOW
BROWN
IGNITER
L/H
CON 5
CON 1
PACTROL CONNECTIONS
CON 6 CON 7 JT1
900386
10
JT2
5. Wiring Details cont.
11
3
HIGH
2
MED
1
LOW
N
AIR CURTAIN
FAN TERMINAL BOX
LOW SPEED
A customer specific control panel wiring
diagram will be supplied with each air curtain
E
N
L3
L2
L1
415 VOLT
3 PHASE +N
50 Hz
SUPPLY
DOOR LOCKED
ISOLATOR
CB
CA
MCB1
20A
E
HIGH SPEED
Diagram 8: Generic control panel wiring
single module (sheet 1)
12
BURNER
R1/1
CA AUX
MCB4
4A
MCB5
4A
BURNER
LOCKOUT
BURNER
LOCKOUT
RESET
PANEL
LIVE
C5(4)
R
COOL/HEAT
RELAY
C5(5)
G
R1
DOOR
INTERLOCK
MAKES AS
DOOR
OPENS
PACTROL P25
COOL/HEAT
DOOR
RELAY
DR
HI/LO
SPEED
CONTACTOR
CB
DR
CA
FAN
CONTACTOR
DR
A customer specific control panel wiring
diagram will be supplied with each air curtain
BMS
INTERLOCK
LINK IF NOT
REQUIRED
ROOM
THERMOSTAT
BREAKS ON RISING
TEMP (EXTERNAL)
AUTO
OFF
MAN
5. Wiring Details cont.
Diagram 9: Generic control panel wiring
single module (sheet 2)
5. Wiring Details cont.
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.
5.1 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.
5.3 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).
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
Warning: never attempt to bypass the
thermal limit
controls as
hazardous
conditions could result.
Fig. C
Fig. D
13
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.
6.1 Tools Required.
Suitable alternative tools may be used.
The following tools and equipment are advisable
to complete the tasks laid out in this manual.
13mm spanner
Cross point
screwdriver
Small flat head
screwdriver
Allen key set
Manometer
10mm spanner
Adjustable
spanner
Adjustable
pipe wrench
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 curtain, 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.
Soft
brush
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 I/D fan.
NOTE: Before removing the I/D fan it will be
necessary to remove the first flue section
after releasing it from the fan/flue adapter.
(See section 8 Fig.20 for details).
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.
Disconnect and remove I/D fan as described in
section 8. Clean off any dust or deposits using a
soft brush paying particular attention to the
impeller. Also remove any dust or deposits from
the finger guard covering the secondary
(cooling) impeller, and the mesh aperture in the
motor cover. Check that the impeller is free to
rotate and that there is no play in the
bearings.
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.
6.4 Emitter tubes.
6.4.1 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
6.2.3 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.
6.4.2 Internal.
To gain access first remove the five retaining
screws from the inspection cover as shown in
Fig.1 overleaf.
14
6. Servicing cont.
Fig.0
Fig.3
Clean out the emitter tubes using a suitable flue
brush/scraper fitted with flexible extension rods.
Fig.1
Fig.4
Remove the six flue box lid retaining nuts from
their captive studs as shown in Fig.2. then
remove lid taking care not to damage the
gasket.
NOTE: To clean the firing legs of the
emitter tubes it is necessary to remove the
burners as described in section 6.2.2.
Fig.2
6.5 Air outlet louvres.
The air outlet louvres should be cleaned with a
soft brush. Check that the louvres are set to the
required angle.
6.6 Air distribution fans.
The air distribution fans can be accessed by
opening the fan lid as described in section 8.
Clean off any dust or deposits with a soft brush
paying particular attention to the impeller. Check
that the impeller spins freely, and that there is
no play in the fan bearings.
The fan(s) can be removed, if necessary, as
described in section 8.
Remove turbulators (5 off) as shown in Fig.3,
and clean off any dust or deposits with a soft
brush.
NOTE: Following any servicing work it will
be necessary to re-commission the air
curtain (See section7).
NOTE: The turbulators are fitted in the
emitter tube non-firing legs only. (See
Fig.4)
15
7. Commissioning.
7.5 Burner gas pressure adjustment
The gas pressure is set for the required heat
input before the appliance leaves the factory,
normally, provided the gas supply to the air
curtain is in accordance with the supply
pressure described on the appliance data plate,
the operating pressure will not require
adjustment. To check the pressure, the following
procedure should be carried out:
7.5.1
Ascertain from section 3 (technical
specifications) of this document, and the
appliance data plate, the correct operating gas
pressure for the air curtain burner.
7.5.2
Turn the control panel cool/heat selector switch
to the 'cool' position.
7.5.3
Remove the screw from the burner pressure test
point of the multi-functional control valve (see
Fig. 5).
This appliance must be commissioned by
a suitably qualified engineer
7.1 Gas connection
Only persons suitably qualified to work on gas
fired appliances may carry out commissioning
and testing. The whole of the gas service
installation including the meter must be
inspected, tested for gas soundness, and
purged in accordance with the current rules in
force.
WARNING: Never use a naked flame for
checking gas soundness.
7.2 Air curtain gas pipework
The gas soundness of the air heater pipework
has been checked prior to leaving the factory.
however during installation, connections may
have been loosened. Check the gas soundness
of the appliance pipework using suitable leak
detection fluid. If any leaks are found they must
be rectified immediately.
Fig.5
7.3 Turning the air curtain on
The following checks should be carried out
before attempting to light the air curtain.
7.3.1
Ensure that the gas supply to the air heater is
turned on.
7.3.2
Ensure that the electrical supply to the control
panel is switched on. Ensure that the control
panel heat/cool selector switch is set to the
'heat' position. The air curtain will now start
automatically.
Note: If the air curtain will not start on initial
start up, the ignition controller may be in
lockout position and require resetting. This
may occur especially if the appliance has been
on stand-by for a prolonged period.
7.4 Air curtain lighting sequence
AB air curtains are fitted with automatic spark
ignition. When adequate airflow for combustion
is proven by an air proving switch, and a
pre-purge period has elapsed, the integral
igniter and multi-functional gas control operate.
The ignition spark ignites the burner and the
flame is detected by a flame ionisation rod
sensor. If a burner flame is not detected, then
the ignition controller proceeds to lockout and
will require manually resetting. Lockout is
indicated by the illuminated burner rocker
switch, and by lockout lamp on the control
panel, and can be reset either by pressing the
illuminated burner rocker switch or the control
panel lockout reset button.
NOTE: If the first lockout reset is not
successful, further investigation will be
required to ascertain the fault.
7.5.4
Connect a suitable manometer to the burner
pressure test point.
Turn the control panel cool/heat selector switch
to the 'heat' position, then wait for burner to
light.
7.5.5
Observe the burner gas pressure reading on the
manometer and compare to the required
pressure.
7.5.6
Adjust if necessary as follows:
First remove the plastic dust cover from the
regulator adjusting screw. Turn the regulator
adjusting screw anticlockwise to decrease
pressure, or clockwise to increase pressure.
(See Fig. 6 overleaf) Replace dust cover.
7.5.7
Set control panel heat/cool switch to the cool
position to turn OFF the burner. Replace the test
point screw (if removed). Relight the burner
and test for gas soundness using suitable leak
detection fluid.
16
7. Commissioning cont.
Fig.6
+
-
Gas flow
17
8. Parts Replacement.
Fig.8
All servicing/maintenance work on this air
curtain should be carried out by suitably
qualified and Corgi registered engineer. Before
commencing any work please ensure that the
gas and electricity supplies are turned off.
Always test for gas soundness with a suitable
leak detection fluid.
8.0 Tools required.
Allen key set
Adjustable
pipe wrench
Adjustable
spanner
8.1.1 Gas valve.
Remove electrical connectors as shown in Fig.9
Fig.9
Cross point
screwdriver
10mm spanner
13mm spanner
8.1 Burner/control assembly.
The major components of the burner/control
assembly can be accessed by removing the two
lid retaining screws located on the right hand
side on top of the air curtain, and swinging the
lid downwards as shown in Figs 7 & 8.
Disconnect the mains gas pipe feeding the air
curtain complete with gas cock. Remove the two
strain relief plate screws (arrowed, Fig.10). The
pipe can only be removed downwards complete
with the gas valve, (see description and Figs. 11
and 12 overleaf).
Fig.7
Fig.10
Strain relief
plate screws
18
8. Parts Replacement cont.
Using a suitable pair of spanners release the
union on the outlet side of the gas valve as
shown in Fig. 11.
The manifold can now be removed downwards
complete with injectors. Fig.14 shows the
manifold with injectors in isolation for clarity.
Fig.14
Fig.11
Remove the two mounting bracket screws as
shown in Fig.12.
8.1.3 Air pressure switch.
Remove the silicon tubing from the rear
connection of the air pressure switch as shown
in Fig.15.
Fig.12
NOTE: only a single tube is fitted to the air
pressure switch on the negative pressure
side.
Fig.15
The valve can now be withdrawn from the air
curtain, and the mounting bracket removed if
necessary
8.1.2 Gas manifold/injectors.
Follow previous steps describing removal of
valve to manifold pipe union. Remove the four
manifold retaining screws as shown in Fig.13.
Remove the two retaining screws as shown in
Fig.16.
Fig.13
Fig.16
Mounting screws
19
8. Parts Replacement cont.
Lift the air pressure switch upwards from the
rear of the mounting plate then remove the three
female spade connectors as shown in Fig.17
then remove switch.
8.1.5 I/D fan.
The I/D fan is mounted on top of the unit
towards the right hand side.
First remove the flue and the fan/flue adapter
from the fan outlet.
Disconnect the mains plug/socket feeding the
fan.
Fig.17
Remove the four 6mm screws (arrowed Fig. 20)
securing the fan to the air curtain flue outlet.
Remove the fan taking care not to damage the
gasket seal.
Securing screws
Fig.20
8.1.4 Ignition sequence controller.
Disconnect the multi-pin connectors from the
ignition controller as shown in Fig.18.
Fig.18
Remove the two fixing screws securing the
ignition controller to the mounting plate as
shown in Fig. 19. then remove controller.
Fig.19
20
8. Parts Replacement cont.
8.1.6 Flame probe.
Remove the flame probe cable spade connector
as shown in Fig.21.
8.1.7 Spark electrode
Remove the HT cable spade connector from the
ignition sequence controller as shown in Fig.24.
Fig.21
Fig.24
Remove flame probe fixing screw as shown in
Fig.22.
Remove fixing screw as shown in Fig.25.
Fig.22
Fig.25
Withdraw spark electrode complete with HT
cable as shown in Fig.26.
Withdraw flame probe as shown in Fig.23.
Fig.23
Fig.26
21
8. Parts Replacement cont.
8.1.8 Overheat thermostats
Remove the two retaining screws securing the
thermostat access lid as shown in Fig.27.
Remove the spade terminals from the manual
reset thermostat as shown in Fig. 30.
Fig.27
Fig.30
Disconnect the spade terminals from the self
resetting thermostat as shown in Fig.28.
Remove the single retaining screw securing the
manual reset thermostat as shown in Fig.31.
Fig.28
Fig.31
Remove the two retaining screws as shown as
shown in Fig.29. and remove.
Remove from location slot complete with bracket
as shown in Fig.32.
Fig.32
Fig.29
22
8. Parts Replacement cont.
Fig.36
8.2 Air distribution fans.
The air distribution fans can be accessed by
removing the retaining screws securing the
hinged lid on the underside of the air curtain.
(See Fig.33)
Fig.33
Fan outlet
Fan closure plate
8.2.2 Fan removal
Identify the feed cable for the fan requiring
removal and disconnect it from its cable
mounted plug/socket. (See Fig.37)
Fig.37
The lid can now be hinged down to access the
fans as shown in Fig.34.
Fig.34
The four bolts securing the fan can now be
removed as shown in Fig.38, and the fan
removed from the air curtain downwards.
Fig.38
8.2.1 Fan closure plate
Before individual fans can be removed it will be
necessary to remove the fan closure plate.
Remove the retaining screws around the
perimeter of the plate. (See Figs.35/36) The
plate can now be removed.
Fig.35
Fan closure plate
Fan outlet
CAUTION: these fan units are heavy.
23
8. Parts Replacement cont.
Fig.39 shows single air distribution fan in
isolation for clarity.
Fig.39
24
9. Spare Parts.
Recommended spares
In order to aid troubleshooting and servicing we
recommend that the components shown in this
section should be stocked.
Item
Description
Part No.
Ignition
controller
106963
Gas valve
twin sol
220/240V ac
Note: Any spare parts or components used
that are not approved by AmbiRad could
invalidate the approval of the appliance and
also the warranty.
Item
2055
Description
Part No.
3 speed air
distribution fan
unit
AB-FAN
Injectors (5 off)
Natural gas:
AB 175N/AB 225N
106962/106810
Propane:
AB 175P/AB 225P
106958/106957
Pressure
switch
201508
Manifold
103201
Combustion
(I/D) fan
200421
Burner
106715
Illuminated
reset rocker
switch
2645
Red neon
2180
Self resetting
limit control
106807
Amber neon
2175
Flame probe
106798
Manual reset
limit control c/w
capillary
106884
Flame probe
lead
900387
Ignition
electrode
c/w HT lead
106797
25
10. Fault Finding.
Ensure gas & electricity
supplies are on, and that
control panel
heat
enable is on to burner.
Burner controls
YES
YES
Is there power
to the burner?
NO
Does the
fan run?
NO
Check:
1. Wiring harness & plugs.
2. Operation of vacuum
switch.
3. Replace fan.
Check:
1. Ignition controller.
Check:
1. Operation of cycling/manual
thermostats. If tripped, diagnose
fault, reset.
2. Check control panel `burner
on` 230V supply.
3. Check any external circuit
breakers/ fuses.
Check:
1. Vacuum switch tube.
2. Emitter tubes, air inlet & vent
for obstructions.
3. Operation of vacuum switch
4. Replace fan.
NO
YES
Check:
1. Ignition controller.
2. Wiring harness.
Does the
vacuum switch
pull in?
YES
Is the burner
sparking?
NO
Check:
1. Integrity of spark leads.
2. Integrity of spark electrode.
assembly & spark gap.
3. Ignition controller.
YES
Does the gas
valve open?
If the heater still fails to
operate normally,
please contact
the AmbiRad
service department.
NO
Check:
1. Ignition controller.
2. Replace gas valve.
Check:
1. Burner inlet pressure.
2. Burner nozzle pressure.
3. Check live & neutral polarity.
4. Check presence of good
earth.
YES
26
10. Fault Finding cont.
Air distribution fans
Power on to control
panel?
NO
Check:
1. Power supply.
YES
All air
distribution
fans off?
Check:
1. Control panel man/off/auto
switch position.
2. Fan circuit breaker(s)
3. Fan contactor and
associated wiring.
YES
NO
Single fan
unit off?
Check:
1. Motor thermal trip (may run
when cool), test motor.
2. Motor wiring.
3. Motor plug/socket.
YES
If the fan(s) still fail to
operate normally,
please contact
the AmbiRad
service department.
27
11. User Instructions.
switch on the burner panel, or the control panel
lockout reset button, providing the lockout
condition has cleared. If lockout re-occurs,
switch off air curtain and call out a service
engineer.
11.1 Important information
This appliance must only be installed by a
competent person in accordance with the
requirements of the codes of practice and the
rules in force in the country of use.
11.1.1 The appliance must be earthed.
11.1.2 Never rest anything, especially ladders,
against the air curtain.
11.3 To switch off the AB air curtain
11.3.1 Rotate the auto/off/manual control panel
switch to the 'off' position. The burner will shut
off, and the combustion fan and air distribution
fans will stop.
11.3.2 If the air curtain is switched off for periods
in excess of one week, it is highly recommended
that both gas and electrical supplies to the air
curtain are turned off.
11.2 To start the AB air curtain
11.2.1 First ensure that the gas supply to the air
curtain is turned on.
11.2.2 Ensure that the control panel auto/off/
manual selector switch is in the manual position,
and that the heat/cool selector switch is in the
heat position.
11.2.3 Switch on electrical supply to the control
panel. The panel live lamp, and the red burner
live neon lamp on the air curtain will illuminate,
the combustion fan and the air distribution fans
will start, and the automatic ignition sequence
will commence.
11.2.4 After completion of an air purge period,
ignition of the burner will occur, and the amber
burner on lamp will illuminate.
11.2.5 If lockout should occur, the red rocker
switch on the burner panel, and the lockout lamp
on the control panel will illuminate. The lockout
can be reset by pressing the illuminated rocker
11.4 Servicing
To ensure continued efficient and safe operation
it is recommended that the air curtain is serviced
regularly by a competent person, once a year in
normal working conditions, but in exceptionally
dusty or polluted conditions more frequent
servicing may be required.
Document reference number GB/AIR/035/1209
The manufacturer, (AmbiRad, address given
below), offers a maintenance service, details of
which are available on request.
For sales related queries please contact the
Nordair Niche address given below.
28