Ambirad Herringbone HB User manual

HERRINGBONE
HB COMBINED
FLUE SYSTEM

Index
General arrangement of Ambi-Rad
Herringbone system
Instructions and installation
Manifold assembly
Fan to flue arrangement
Commissioning
Control system
Service instructions
7
6
5
4
3
2
1
1

The Ambi-Rad Herringbone HB combined
manifold system may consist of either ‘U’
tube or linear heaters, linked into a common
aluminium manifold system, which in
turn is coupled to one hot gas vacuum
fan to ‘evacuate’ the products of
combustion to atmosphere via a flue
system.
This document should be used in
conjunction with the specific product
installation manual i.e AR or Optima Series.
Please refer to the design manual 042/93
to ensure correct manifold design.
The following appliances are tested and
certified by an accredited test house for
use on natural gas and propane:
AR Series BG/EC – 87/95/214
Optima BG/EC – 87/95/308
The system is controlled via an Ambi-Rad
black bulb thermostat whose controller
is housed in a lockable cabinet with fan
starter for Type ‘0’ fan only and time switch.
The Ambi-Rad Herringbone HB combined
manifold system layout should be designed
to be as compact as possible with the final
connection to the hot gas vacuum fan
approximately central in the manifold
system. Please refer to document Ambi-Rad
Herringbone design manual 042/93.
The manifold system should be arranged
to fall slightly in the direction of the hot
gas vacuum fan. This ensures that any
condensation formed in the manifold
on cold start and cool down is not trapped
or allowed to drain back into the heater unit
and will flow towards the condensate trap
located at the vacuum fan end of the
manifold system. (See figure 8a for
condensate trap arrangement)
The exhaust flue should be adequately
supported from the building structure and
installed in accordance with the British
Standard Code of Practice – Flues for Gas
Appliances, Local and Ministry Authorities
and Building Regulations. Alternatively, a
telescopic through the wall discharge duct is
available for either Type ‘0’, or Type ‘2’ fan
(available from Ambi-Rad).
Ambi-Rad will, upon receipt of a proposed
drawing showing a Herringbone system,
check the pressure drop of the manifold
system to ensure it does not exceed the hot
gas vacuum fan design criteria.
1.1 Standards
The Ambi-Rad heater must be installed
in accordance with the relevant
provisions of the Gas Safety
(Installations and Use) Regulations 1984
(as amended). Due account should also
be taken of any obligations arising from
the Health and Safety at Works etc. Act
1974. In addition the installation must
be carried out in accordance with the
current I.E.E. Regulations. The Building
(Standards) (Scotland) Consolidation
Regulations, the requirements of BS
5440:Part 1:1990, BS 6891:1998, BS
6896:1991 and any other relevant British
Standards and Codes of Practice.
1.2 Ventilation requirements
Permanent ventilation is required as
follows:
Natural ventilation
(preferably at low level)
Up to and including 60kW - 4.5cm2/kW,
over 60kW - 270cm2+ 2.25cm2/kW
in excess of 60kW total input.
Forced ventilation
Minimum proven air flow –
2.35m3/h per kW of total rated input.
For detailed information please refer
to Ambi-Rad design manual and/or
BS 6896:1991, Installation of Gas Fired
Overhead Radiant Heaters for Industrial
and Commercial Heating.
1 General arrangement of
Ambi-Rad Herringbone
2

3.1 Method of jointing aluminium tube
Using the applicator gun exude 4mm
diameter bead of high temperature
silicon jointing compound externally
round the end of the fitting and
internally round the end of the tube.
(See figure 2)
Enter the fitting into the tube using
a slight rotating movement to spread
the jointing compound uniformly
until a penetration of 75mm (3in)
is achieved.
Note The silicon jointing compound
remains workable after application
for only 5 minutes.
Figure 1 Typical Herringbone heating arrangement using AR22HB and HB22AR heaters
3 Manifold assembly
2 Instructions and installation
After fixing the heaters in the desired
position, the manifold system should be
laid out on the floor, where possible, to
the design layout before erecting.
After allowing for a minimum of 75mm
(3in) of penetration of the fitting into the
tube, cut the tubes to the lengths required
and remove all burrs and wipe off any
grease or oil with a clean rag.
Secure the joint by drilling through
the tube and fitting and fix with three
pop rivets at 12 o’clock, 4 o’clock and
8 o’clock positions. 3-5mm (3/16in)
diameter pop rivets are recommended.
(See figure 3)
3.2 Damper assembly
The damper assembly secured to
the outlet end of the heater unit
must be located with its damper blade
vertical and left in the closed position.
The manifold tube to be sealed and
secured (as described in figures 2
and 3) to the damper assembly.
For damper assembly see figure 4.
3

Figure 2
Figure 3
Figure 4
Important – fit damper in vertical position
Gas flow
Important – fit rivets and jointing compound, SEAL ALL JOINTS.
4

Manifold pipe size (mm) Maximum distance between supports (m)
100 2.4
150 3.0
3.3 Manifold suspension
The manifold should be supported
by chain, stainless steel flexible wire,
or other flexible means from the roof
structure to allow movement caused
by thermal expansion. For maximum
support centres see figure 5.
Flexible couplers (supplied by
Ambi-Rad) must be inserted within
the manifold system to allow linear
expansion to take place and prevent
stress and strain on the system.
Note The manifold must be supported
either side of the flexible coupler.
Where the HB heaters are to be
inclined/wall mounted, the manifold
must be installed at the same height as
the centre of the emitter tube. For
typical wall mounting bracket
arrangement see AR installation
manual (GB/ARE(E)079/0501).
Figure 5
3.4 Condensate trap
A condensate trap assembly must be
provided at the end of the manifold
system before the hot gas vacuum fan.
(See figure 8a)
The minimum depth of the condensate
collecting chamber shall be 305mm
(12in) and the minimum depth of the
condensate drain pipe ‘U’ trap shall
be 457mm (18in) deep.
The end cap of the collecting chamber
to be fitted with a flush flanged tank
connector. Any protrusion to be
removed leaving the inside flush
with end cap (see figure 9). The end cap
to be sealed with silicon jointing
compound and pop riveted in position.
All condensate drains from the flue
collecting chamber to the disposal point
shall be corrosion-resistant material of not
less than 22mm internal diameter. Copper or
copper based alloy shall not be used for
condensation drains. See reference
BS 6896:1991. Condensate drain pipes must
be protected against the effects of freezing.
5

4 Fan to flue arrangement Figure 6 Dimensions of fan outlet – Type ‘0’ fan
Type ‘0’ fan
Type ‘2’ fan
Do’s Don’t
Check design pressure drop. Install system with extra 90ºbends without asking
Ambi-Rad if the system will operate correctly.
Check for corrosive industrial process in proposed building – Run drains in copper pipe as it will corrode.
eg. cleaning, electroplating, printers using sugar powder etc.
Drain all flue ducts and seal all joints. Install flue going upwards without fitting a drain point
at lowest level.
Secure joints with pop rivets as well as sealing compound. Fit fan with outlet pointing vertically upwards or with top
(See figures 2 and 3) horizontal discharge.
Fit drain traps before and after fans. (See figure 8) Fit damper assembly upside down, on its side or the wrong way
round. (See figure 4)
Fit expansion joints before fan and at intermediate points on the
Herringbone system.
Run drains in galvanised steel or plastic pipes.
Follow guide to Combined Flue Heating System.
Do’s and don’ts of Herringbone systems
The Type ‘0’ and Type ‘2’ vacuum fans
have bottom horizontal discharge with
rectangular connections (flanged on the
type 0) and must be mounted in that
position by means of the fan support stool
onto a suitable platform or brackets fixed to
the building structure. For details of the fan
outlet flange fixing holes see figure 6. For
details of fan mounting bracket and fixing
down holes see figure 7.
aA conventional flue arrangement.
(See figures 8d and 8e)
bA telescopic through the wall flue.
(See figure 8c)
Where a conventional flue is to be installed,
Ambi-Rad supply an aluminium
transformation piece to which a150mm
(6in) diameter flue should be attached.
The maximum length of flue which may be
connected to the fan outlet must be
calculated in accordance with the Ambi-Rad
Herringbone design manual (Ref 042/93)
and must be adequately supported from the
building structure.
Exhaust flues should be installed in
accordance with the British Standard Code
of Practice BS 5440: Part 1:1990 – Flues for
Gas Appliances, I.E.E. Regulations, Local
Ministry Authorities and Building
Regulations.
6

Figure 7 Vacuum fan mounting details
Fan type ‘0’ ‘2’
A 124 80
B 38 35
C175 174
D 7.1 7
E209 125
F 153 100
G42 25
H 239 120
J 340 210
K 332 205
L 363 215
All dimensions are in millimetres.
see Fig 6
7

Conventional fan to flue arrangements
Figure 8a High fan arrangement
Figure 8b Low fan arrangement
Figure 8d Conventional flue arrangement - roof exit
Figure 8e Conventional flue arrangement - wall exit
Figure 8c Stainless steel telescopic through the wall
arrangement (available for Type ‘0’ and Type ‘2’ fans)
Figure 9 Collecting chamber arrangement
8

Figure 10Damper settings
5 Commissioning
Inspect installation and ensure it has been
carried out in accordance with these
instructions.
Ensure that electrical and gas supplies are
isolated.
The gas supply should be purged and
tested for soundness in accordance with the
British Standard BS 6891:1998,
BS 7671:1992, IGE/UP/2 and any other
British Standards and Codes of Practice.
Ensure that the settings of any time switch
and thermostat are such that the heating
system will be required to operate (or put
the mode switch to ‘constant’).
Before attempting to start up the heating
system it is essential to perform the
preliminary balancing of the vacuum level at
each burner unit.
Isolate each heater unit by unplugging each
electrical connector and closing each gas
isolating valve.
Heater type Damper setting when hot (mbar) Heater type Damper setting when hot (mbar)
AR13SHN/22 1.7 ARE13SHN/22 1.1
AR13SHP/22 1.7 ARE13SHP/22 1.1
AR22SHN/27 1.4 ARE22SHN/27 1.1
AR22SHP/27 1.4 ARE22SHP/27 1.1
AR22SHN/32 1.4 ARE22SHN/32 1.1
AR22SHP/32 1.4 ARE22SHP/32 1.1
AR22SHN/36 1.4 ARE22SHN/36 1.1
AR22SHP/36 1.4 ARE22SHP/36 1.1
AR22SHN/39 1.4 ARE22SHN/39 1.1
AR22SHP/39 1.4 ARE22SHP/39 1.1
AR35SHN/33 1.5 ARE35SHN/33 1.2
AR35SHP/33 1.5 ARE35SHP/33 1.2
AR35SHN/42 1.2 ARE35SHN/42 1.0
AR35SHP/42 1.7 ARE35SHP/42 1.0
AR35SHN/51 1.0 ARE35SHN/51 1.0
AR35SHP/511.5 ARE35SHP/511.0
AR40SHN/42 1.6 ARE40SHN/42 1.4
AR40SHP/42 1.4 ARE40SHP/42 1.4
AR45SHN/50 1.9 ARE45SHN/50 1.6
AR45SHP/50 2.0 ARE45SHP/50 1.6
AR45SHN/60 2.0 ARE45SHN/60 1.9
AR45SHP/60 2.3 ARE45SHP/60 1.6
AR50SHN/50 1.9 ARE50SHN/50 1.8
AR50SHP/50 2.0 ARE50SHP/50 2.3
AR50SHN/60 2.0 ARE50SHN/60 1.8
AR50SHP/60 2.3 ARE50SHP/60 2.3
N & P refer to natural gas or propane respectively.
Adjust the damper at exit of each heater
using a 4mm hexagon wrench in the M8
locking screw. Observing the vacuum
reading using a ‘U’ tube manometer
connected to the vacuum test point (see
figure 4) set each damper in turn to give a
hot conditions reading as below.
Referring to each unit
Open isolating valve and test gas
connections for soundness using leak
detecting solution. Remove the combustion
chamber cover plate by unscrewing the
fixing screws. Take care not to damage the
sealing gasket. Inspect the burner and
electrode assemblies ensuring these are
securely fixed and all electrical connections
securely made. Replace the cover plate
ensuring that the sealing gasket is correctly
positioned and the screws are fully
tightened. The heater will not operate until
this plate is refitted.
Remove the safety control housing cover
plate by unscrewing the securing screws
and folding down/lifting off the plate.
Ensure all internal components are securely
fixed and all connections securely made.
Reinsert the electrical connector to the
burner control assembly.
To allow the heater to start up it is
necessary to switch off the whole system
at the time switch or manual switch and
allow the fan to stop completely before
switching on again. At this point the
individual heater unit will start up with
the following sequence.
The red mains on lamp will illuminate and
the main fan will start to run. Safe-start
checks are carried out automatically. After
the fan has run up to full speed and a
satisfactory vacuum condition has been
established at the burner, a purge period of
approximately 9 seconds will commence.
At the end of the purge period the ignition
sequence will commence. The spark ignition
will be energised producing a spark at the
ignition electrode. The gas solenoid valve
is energised and will open.
9

If ignition is successful the flame is detected
by the flame sensing probe and the ignition
spark is switched off. The amber burner on
lamp indicates that the gas solenoid valve
is energised.
If ignition is unsuccessful the gas valve is
closed and the spark ignition de-energised
after approximately 4 seconds. After
unsuccessful ignition attempt the electronic
sequence controller will lock-out the red
mains on lamp only will remain illuminated.
To reset this lock-out condition, switch
the power supply to the system, wait until
the fan stops completely then restart it. If
repeated lock-out occurs, investigate the
cause.
Note If an individual burner assembly unit
is switched off and reconnected it cannot
restart. The fan must stop running before the
burner can be restarted.
To shut down the heaters switch off the
power supply to the system. Automatic
control of the heating system is achieved
through the lockable control panel,
incorporated in the electrical supply, which
may contain a time switch, black bulb
controller with day and night settings, a 3
position mode switch giving constant on/off
auto control and fan starter. It is essential to
allow a delay of 30 seconds after switching
off heaters before attempting to restart the
system.
If at any time after completion of the start
up sequence loss of flame should occur, the
electronic sequence controller will attempt
to re-ignite. If this is unsuccessful, heater
lock-out will occur.
To set the burner gas pressure
Close gas valve. Unplug mains input
connector to heater. Unscrew the fixing
screws of the safety control housing lid and
remove pressure test point screw and
connect a ‘U’ tube manometer to the
pressure test nipple located on the
combination valve. Remove the cover from
the pressure regulator to reveal the
adjusting screw.
Replace mains input connector, open gas
valve and start system.
Using a suitable screwdriver, adjust the
pressure regulator, turning the screw
clockwise to increase the pressure or
anti-clockwise to decrease the pressure.
Set the burner pressure to the required
figure given on the data label. Switch off
the heater by pulling out the mains
connector. Disconnect ‘U’ tube manometer
and refit screw in pressure test nipple. Refit
cover of pressure regulator. Replace cover
plate on safety control housing and refit
screws.
Burner ignition
To re-ignite heater, switch system off at
control panel. Wait until fan stops
completely and then restart system.
Re-ignition
Check the operation of the flame safeguard
equipment as follows:
With the heater running normally switch off
the gas supply at the appliance isolating
valve. Observe that the burner on lamp
extinguishes within 1 second. After a purge
period of approximately 9 seconds the
heater should attempt to re-light and if the
gas isolating valves have been left off,
lock-out should occur, indicated by power
light only being illuminated and fan
running.
Vacuum proving switch
Check the operation of the vacuum proving
switch as follows:
With the heater running normally, pull out
the mains input connector. Pull off the
silicone tube connecting the vacuum switch
to the combustion chamber. Observe for at
least 20 seconds that there is no attempt to
re-ignite. Then replace the silicone tube.
Replace the safety control housing lid and
reconnect the mains input connector.
To re-ignite each heater in the system, the
fan must stop running. Switch system off
at the control panel. Wait until fan stops
completely and then restart system.
Repeat the above procedure for each of the
heater units in the heating system.
Balancing system
Important When all the heaters have been
commissioned as above, the vacuum settings
must be finally balanced in the hot condition.
Start all burners up and allow them to run
for at least 20 minutes. With the use of a ‘U’
tube manometer determine vacuum reading
at the damper assembly on each heater. (See
figure 4 for vacuum test point)
The damper should be readjusted and set at
a hot condition reading as shown in figure 10
for the appropriate size heater and model.
It will be noted that the emitter has a
tendency to bow when hot, this is normal
and quite acceptable.
10

Figure 11 Logic sequence for Herringbone control panel
6 Control system
The control system must be installed in
accordance with the design specification.
6.1 Control panel design
Ambi-Rad control panels are available
either as standard units to control
single or multiple zones of heaters
utilising the Ambi-Rad black bulb
radiant thermostat. Special control
functions are available on request.
Herringbone control panels use the
logic in figure 11 to operate in a safe
and satisfactory manner.
6.2 Installation of control panel
To install the Ambi-Rad control panel
remove the plastic plugs from the four
9mm diameter holes in the back of the
control box. Using these holes fix the
box in a convenient position to a
suitable plugged wall or solid structure
with No. 10 gauge wood screws or
6mm diameter bolts or set screws.
Access to the holes may be gained from
the inside of the box without the
necessity of removing the wiring
chassis. Make the electrical connections
in accordance with figure 12a or 12b
and cut holes in the removable gland
plate provided in the box. Conduit or
strain relief glands should be used.
Power onto panel
Mode switch in off position Mode switch in auto position Mode switch in constant position
(one or all zones)
No heaters on
Time clock off Time clock on
Break contacts 8 & 9 on Make contacts 8 & 9 on
black bulb controller black bulb controller (via relay or
time clock contacts for each zone
Control on night temperature Control on day
setting for frost protection temperature setting
Call for heat by black bulb controller
controlling each zone or all heaters
Delay start of Herringbone fan for 30 seconds
to ensure vacuum switch on heaters is
broken (only required for 2 zones or
more on one fan)
Switch on the power suuply to the
Herringbone fan and power supply to
heaters simultaneous
Individual heater vacuum switch senses combustion vacuum
Individual heaters start ignition sequences
Zone control switches off
Other zones carry on firing (if fitted)
Zone control calls for heat
Power off to all heaters or zones
and to stop Herringbone fan
(Possible
alternative
control
function to
override
temperature
controller)
11

Figure 12a Single zone Herringbone control panel wiring diagram for Type ‘2’ fan (single phase) incorporating the
ARBB65 black bulb control thermostat
12

Figure 12b Wiring diagram for Type ‘0’ fan (single phase)
13

Fan type ‘0’ ‘2’ *
Power watts 550 120
Running current (overload rating) amps 3.8 0.8
Phase Single Single
Voltage 240 240
Vacuum fan characteristics
* Overload not required.
6.3 Instructions for fixing sensor unit
aA position should be selected 1.5m
from the floor where the sensor will be
free from undue draughts and if
necessary between 4 and 5m from one
of the heaters to be controlled. Avoid
placing the sensor where it will be in
an area shadowed from radiant heat
(behind racking etc.).
bRemove the cover of the sensor unit by
undoing the four screws.
cFix the base to the wall with two
screws.
dConnect the sensor using a three core
cable of not less than 0.5mm2.
Maximum length of cable is 200m if
0.5mm2is used. Secure wires in the
cable gland provided (alternative rear
cable entry available – remove gland
and seal with grommet if rear entry
used).
eWire sensor to controller in accordance
with wiring diagram. (See section 6)
fRefit the sensor to the base.
6.4 Fan starter overload
The red reset button on the fan starter
is used only to restart the fan should it
cut out due to overload or malfunction.
Should repeated lock-out occur then a
qualified electrician should be
consulted.
Figure 13 Black bulb sensor and controller
14

AMBIRAD is the registered
trademark of Ambi-Rad Limited.
Due to continuous product
innovation, Ambi-Rad reserves
the right to change product
specification without due notice.
Document reference number GB/HB/134/1103
Ambi-Rad Limited Fens Pool Avenue
Brierley Hill West Midlands
DY5 1QA United Kingdom
Telephone [phone]
Facsimile 01384 489707
UK sales email [e-mail]
Website www.ambirad.co.uk
7 Service instructions
Under normal working conditions, it is recommended that the Ambi-Rad heater has a routine service once per year. In exceptionally dirty
or dusty conditions, more frequent servicing may be desirable. Servicing work should be carried out by a qualified gas servicing engineer.
For heater routine service, trouble shooting checklist and spares list, please refer to the AR/ARE or Optima Installation Manual.