Gas fired room sealed unit heaters
centrifugal
TECHNICAL INFORMATION, ASSEMBLY
INSTRUCTIONS, USE AND MAINTENANCE
RS/UHC / UF RS/UHC-2 / 2UF
BENSON HEATING
LUDLOW ROAD
KNIGHTON
POWYS,
LD71LP U.K.
August 2003
Benson Heating is a Division of
Benson Climate Systems Ltd
1
COMPLIANCE NOTICES
The Benson RS/UHC range of warm air heaters detailed herewith are manufactured for Benson Heating within
the parameters of ISO 9002.
The Benson RS/UHC range has been independently tested and assessed, and has been found to meet the
Essential Requirement of the following European Directives:
Gas appliance Directive (90/396/EEC)
Machinery Directive (89/392/EEC) 91368/EEC 93/44/EEC 93/65/EEC
Low Voltage Directive (73/23/EEC
Electromagnetic Compatibility Directive (98/336/EEC and 91/31/EEC)
Product Liability Directive (65/374/EEC)
The manufacturer has taken reasonable and practical steps to ensure that Benson RS/UHC range of Heaters are
safe and without risk when properly used. These heaters should therefore only be used in the manner and
purpose for which they were intended, and in accordance with the recommendations detailed herewith.
The heaters have been designed, manufactured, assembled, inspected, and tested, with safety and quality in
mind, there are certain basic precautions which the installer and user should be aware of, and they are strongly
advised to read the appropriate sections of the information pack accompanying the heater, prior to installation
or use.
Benson Heating supports all new products being supplied to their customers with a comprehensive information pack; this
clearly defines mandatory instructions for the safe installation, use, and maintenance, of the appliance(s).
Where proprietary items are incorporated into Benson Heating products, detailed information and instructions are also
provided as part of the information pack.
It is the responsibility of the installer, owner, user, or hirer, of such products supplied by Benson Heating, to ensure that
they are familiar with the appropriate information/manuals, supplied by the manufacturer, and that they are suitably
aware of the purpose of the manuals and the safety instructions. In addition, operators must be suitably trained in the use
of the appliance so as to ensure its continued safe and efficient use.
Benson Heating has a commitment to continuous improvement, and therefore reserves the right to amend or
change the specification of the RS/UHC Heater range subject to agreement from The Notified Body.
Contained within the text of the manual, the words 'Caution' and 'Warning' are used to highlight certain points.
Caution is used when failure to follow or implement the instruction(s) can lead to premature failure or damage to the
heater or its component parts.
Warning is used when failure to heed or implement the instruction(s) can lead to not only component damage, but also
to a hazardous situation being created where there is a risk of personal injury.
RANGE
Notified Body PIN Reference is 0694BN3750
Type
SINGLE STAGE
STANDARD
UP RATED FAN
Model
Code
Model
Code
TWO STAGE
STANDARD
UP RATED FAN
Model
Code
Model
Code
1
RS/UHC80
3NIGBCR026
RS/UHC80/UF
3NIGBC1026
RS/UHC80-2
3NIGB2A026
RS/UHC80-2UF
3NIGB22026
2
3
4
5
6
RS/UHC105
3NIGBCR036
RS/UHC105/UF
3NIGBC1036
RS/UHC105-2
3NIGB2A036
RS/UHC105-2UF
3NIGB22036
RS/UHC140
3NIGBCR046
RS/UHC140/UF
3NIGBC1046
RS/UHC140-2
3NIGB2A046
RS/UHC140-2UF
3NIGB22046
RS/UHC200
3NIGBCR066
RS/UHC200/UF
3NIGBC6066
RS/UHC200-2
3NIGB2B066
RS/UHC200-2UF
3NIGB23066
RS/UHC260
3NIGBCR086
RS/UHC260/UF
3NIGBC6086
RS/UHC260-2
3NIGB2B086
RS/UHC260-2UF
3NIGB23086
RS/UHC325
3NIGBCR0106
RS/UHC325/UF
3NIGBC6106
RS/UHC325-2
3NIGB2B106
RS/UHC325-2UF
3NIGB23106
VERSION SINGLE STAGE
The heater has a single stage gas valve, and a standard centrifugal fan. An optional uprated fan version is available for
installations that require higher static pressures.
VERSION TWO STAGE
The heater has a two stage Hi /Lo gas valve, and a standard centrifugal fan. An optional uprated fan version is available
for installations that require higher static pressures.
2
GUARANTEE
The heater is supplied with a 2 year warranty on all parts.
In addition to this there is also a 10 year time related warranty on the combustion chamber.
The warranty commences from the date of despatch from the manufacturer, and is subject to the terms detailed within
the manufacturer 'conditions of business'.
The warranty may be invalidated if:
a) The warranty registration/commissioning card has not been completed and returned to the manufacturer
b) The installation is not in accordance with the general requirements of this manual
c) The flue arrangement and air supply for the heater are not in accordance with the manufacturers
recommendations, codes of practice, or similar standards
d) Air flow through the heater is not in accordance with the manufacturers technical specifications
e) Internal wiring on the heater has been tampered with or unauthorised service/repairs undertaken
f) The main electrical supply input to the heater has been interrupted during the heating mode
g) The heater has been subject to and affected by the ingress of water in any form
h) The heater is not operated at the rating(s) laid down in the manufacturers technical specifications
i) The heater has not been operated or used within the normal scope of its intended application
j) The manufacturer's recommended minimum service requirements have not been complied with
All warranty claims must contain the following information to enable processing to take place;
(1) Heater model
(2) Heater serial number
(3) Order reference/date of order, together with full installation details (name and address)
(4) Details or symptoms of fault
(5) Installers name and address.
Faulty parts must be returned to the manufacturer Spares Department, the address of which is provided on the rear
cover of this manual. Any such parts will undergo inspection to verify the claim. Replacement parts supplied prior to this
may be charged, and a credit supplied upon subsequent validation of the warranty claim. Consumable items are
specifically not included within the scope of the warranty.
Notification is required immediately a fault is suspected. The manufacturer will not accept responsibility for any
additional damage that has been caused, expense incurred, or consequential loss resulting from any failure of
the heater(s).
Ensure that the heater is able to operate within the parameters shown on the data plate and the technical data
within the manual.
Incorrect gas settings may lead to condensation within the combustion if to low, and overheating if to high both
will cause damage to the heat exchanger.
Any reference made to Laws, Standards, Directives, Codes of Practice or other recommendations governing the
application and installation of heating appliances and which may be referred to in Brochures, Specifications, Quotations,
and Installation, Operation and Maintenance manuals is done so for information and guidance purposes only and should
only be considered valid at the time of the publication. Manufacturer cannot be held responsible from any matters arising
from the revision to or introduction of new Laws, Standards, Directives, Codes of Practice or other recommendations.
3
INDEX
GENERAL
Description of equipment
Identification
Description
Technical data
Wiring diagram
Remote control connections
page.
“
“
“
“
“
5
6
7
9
10
14
FOR THE USER
Operation
Servicing
Heater indication lights
Receipt of product and transport
Dimension and weight
“
“
“
“
“
15
15
16
16
17
FOR THE INSTALLER
Installation
Installation clearances
Examples of installation
Accessories
Gas connection
Flue and combustion options
Electrical control panel and circuit board
Electrical connections
“
“
“
“
“
“
“
“
19
20
21
22
23
24
28
28
TECHNICAL ASSISTANCE SERVICE
Duct connection
Return air connections
Protection
Pre commissioning checks
Initial start up
Gas conversion
Thermostat
Fan
Control
Maintenance
Fault finding
“
“
“
“
“
“
“
“
“
“
“
29
30
30
30
31
32
34
35
35
36
38
4
DESCRIPTION OF EQUIPMENT
Control and safety thermostat
The heater is controlled by three thermostats pre set to the
following.
Heat exchanger
• Stainless steel construction easily accessible for
inspection and cleaning and maintenance operations.
• Patented exchange elements made in stainless steel
modular sections with large surface area, trapezoidal in
section with swirl impressions for which give thermal yields
of over 90%. The exchange elements have no welded
joints or seams near to the burner flame so as to avoid
exposure of any weak points.
LM Limit thermostat (100°C)
Capillary type. Manual Reset
Act as a safety device and shuts down the burner if the
heater goes to overheat. The yellow light will flash when in
overheat. The LIMIT thermostat is reset by the removal of the
plastic cap situated on the control panel inside the heater, and
manually pressing the reset button, after first ensuring that the
fault has been rectified. (calibrated at100°C). Replace cap
after resetting thermostat.
Flue outlet with integral flue venter to assist dispersal of
combustion gasses.
External casing
Encloses all controls giving a good aesthetic appearance and
streamlined look whilst allowing for easy inspection.
The casing consists of removable panels and also includes:
A burner compartment which is totally sealed off, with an
inspection door;
Radiant heat insulation on the surfaces closest to the heat
exchanger;
Outlet grille for directing the warm air.
TR Regulatory thermostat (0 – 90°C)
Capillary type. Automatic reset.
The thermostat monitors the temperature of the airflow and will
shut down the burner if the set level is exceeded (calibrated at
70°C). Once the fan has sufficiently cooled the heat
exchanger, the burner will automatically relight. The yellow
indication light will flash until the burner relights. If this fault
persists the cause should be investigated.
SND Control probe (0 – 40°C)
Connected in series with the thermostat TR. The probe will
start the fan when the temperature reaches 30°C
(approximately 30 seconds from burner ignition). When the
desired room temperature is reached and the burner shuts
down, the probe will allow the fan to run for approximately 3minutes until the heat exchanger has cooled sufficiently.
The probe also monitors the operation of the TR thermostat
and if a fault is detected will change the yellow flashing light to
a continous on light. In addition to this the SND probe monitors
the temperature of the return air and will switch off the fan prior
to the 3-4 minute run on time if the heat exchanger has cooled
sufficiently (this avoiding cold air flow from the heater).
Fan assembly
One or two centrifugal fans operated by a single electric
motor via pulleys and belts the motor pulley is adjustable to
give effective cooling of the combustion / heat exchanger.
The position of the fan(s) produce greater effective cooling of
the combustion chamber, optimising the heat exchange and
avoiding overheating.
An up rated fan is also available.
Control and protection equipment
This is electronic with ionisation flame detection and ignition
controls.
The equipment controls and monitors the operation of the
burner in the following sequence.
Checks the differential pressure switch operated by the flue
venter is in the closed position and the flue venter is working;
Checks the air temperature of the combustion chamber
(below 100ºC)
Opens the gas solenoid valve;
Starts burner ignition;
Detects flame signal from flame probe and allows normal
heater operation.
Failure in any of the above sequence will result in the control
box shutting the gas valve and stopping the heater.
The Heater will go to lockout and can be only be reset
manually by pressing the red light on the front of the
equipment.
Differential air pressure switch
This switch will shut the gas valve if the flue venter fails or
there is an obstruction in the flue, or in the air inlet preventing
the flue venter from operating.
Flue venter
This consists of a centrifugal fan which
Is run by an electric motor with self-cooling rotor the cooling air
is supplied through a duct pipe situated in the axial fan air flow.
Indication lights
These consist of three different coloured lights on the front of
the heater:
• Green light – indicates normal working. Illuminates when
the gas solenoid valve opens
• Yellow light – indicates the operation of the LM, TR and
SND thermostat.
• Red light - to indicate lockout of the heater by the control
circuit failure.
• Reset button to reset the lockout
Gas solenoid valve
The multifunctional 1 stage gas valve (Single Stage)
and 2 Stage gas valve (Two Stage ) consists of:
• Safety solenoid valve
• A regulatory solenoid valve
• A pressure regulator
• A gas filter
Flue spigot
A flue spigot (100mm) is situated at the rear of the heater for
connection of flue pipes.
Atmospheric multigas burner assembly
Consisting of:
• Galvanised steel manifold
• Visual monitoring aperture for the electrodes and flame
observation
• 3 or 6 stainless steel burner bars
• Ignition and Detection electrodes
Combustion air spigot
A combustion air spigot (100/150mm) with a safety mesh of
less than 16 mm Ø on the rear of the heater allow for
connection of combustion air pipe
Note: the type 4-5-6 are equipped with two gas manifolds,
each manifold has an ignition electrode.
5
IDENTIFICATION
If the TECHNICAL DATA is lost or damaged ask
Benson Technical Department for duplicate .
Check code and model is as data plate.
Position of data plate
Manufacturer
AIR HEATER
Model
Serial Number
Country
PIN
Category
Code
Type
Year
Nominal Heat INPUT
kW
Nominal Heat OUTPUT
kW
m3/h
Air Flow (+15°C)
Electrical Supply
Electrical Power
W
Protection Rating
GAS TYPE
Supply Pressure
mbar
Head Pressure
mbar
Injector Diameter
mm
Gas Consumption
m3/h
Packing label position
Code
Model
Serial No
6
DESCRIPTION
Type 1÷4
NOTE:
Heaters type 1, 2, 3 have a single burner manifold.
Heaters type 4 have two burner manifolds
19. Red light lockout indication
20. Lockout reset
21. Gas inlet connection
22. Electrical connections
23. Combustion intake air spigot
24. Flue spigot
25. Inlet casing
26. Fan Motor
27. Centrifugal Fan
28. Gas Solenoid valve
29. Ignition electrode
30. Gas pressure manifold test nipple
31. Flame detection electrode
32. Flame check aperture
33. Flue venter
34. Air inlet grille
35. Base plate front
36. Rear support
1. Regulation thermostat SND
2. FAN thermostat TR
3. LIMIT thermostat LM
4. Flue venter inspection door
5. Flue pipe
6. Flue manifold
7. Outlet Grille
8. Controls compartment
9. Heat exchanger
10. Burner plate insulation
11. Gas injector
12. Combustion chamber
13. Gas manifold
14. Burner bars
15. Flue ducting
16. Deflector
17. Green power on light
18. Yellow limit indication light
7
Type 5 and 6:
NOTE:
Heaters type 5 are supplied with 2 opposing burner manifolds
Heaters type 6 are supplied with 4 opposing burner manifolds
1. Regulation thermostat
2. LIMIT thermostat
3. FAN thermostat
4. Flue venter inspection door
5. Flue pipe
6. Flue manifold
7. Outlet Grille
8. Controls Compartment
9. Heat exchanger
10. Gas manifold
11. Gas injector
12. Combustion chamber
13. Burner plate insulation
14. Burner tubes
15. Ignition transformer
16. Left burner casing
17. Flue ducting
18. Deflector
19. Green power light
20. Yellow limit indication light
21. Red light lockout indication
22. Lockout reset
23. Gas inlet connection
24. Cable grips
25. Combustion intake air spigot
26. Flue spigot
27. Inlet casing
28. Fan Motor
29. Centrifugal Fan
30. Gas Solenoid valve (2 on type 5 and 6)
31. Ignition electrode
32. Gas pressure manifold test nipple
33. Flame detection electrode
34. Flame check aperture
35. Gas pressure manifold test nipple
36. Air inlet grille
37. Rear support
38. Base plate
8
TECHNICAL DATA
DESCRIPTION
HEAT OUTPUT
HEAT INPUT
(Nett)
EFFICIENCY
AIR FLOW +15°C
MAX AIR OFF (ΔT)
HEAT INPUT MIN (two stage)
MIN AIR OFF (ΔT) (two stage)
STATIC PRESSURE (standard)
STATIC PRESSURE (uprated)
THERMOSTAT CALIBRATION
- TR (auto reset)
- LM (manual reset)
- SND (auto reset)
FAN OPERATION
- Fan on
- Fan off
Air pressure switch setting
Maximum flue resistanceI
CENTRIFUGAL FAN
- Type
- Number
ELECTRICAL SUPPLY
RATED INPUT standard motor)
RATED INPUT (up rated motor)
RUNNING CURRENT MAX( standard
motor)
RUNNING CURRENT MAX (up rated
motor)
ELECTRICAL PROTECTION
GAS CATEGORY
INSTALLATION TYPES
OPERATIONAL LIMITS
- Temperature
- Relative humidity (non condensing)
WEIGHT (standard)
WEIGHT (up rated)
NATURAL GAS G20
- Number of injectors
- Diameter of injectors
- Inlet pressure
- Head pressure max
- Head pressure (two stage)
- Consumption max (1)
- Consumption min (1) (two stage)
PROPANE GAS G31
- Maximum gas head pressure
- Minimum gas head pressure (two stage )
- Consumption max (2)
- Consumption min (2) (two stage)
Mass products of combustion max
(1)
(2)
1
23,0
78.500
25.4
86.000
90,1
1.820
37
15,8
25
2
30,5
104.000
33.8
115.000
90,2
2.920
31
21,0
21
500
450
TYPE
3
4
41,7
58,6
142.000 200.000
46.3
65.0
158.000 224.000
90,1
90,1
4.130
5.900
30
30
28,8
40,5
20
20
200
440
470
UNIT
5
76,6
261.500
85.0
290.000
90,1
7.900
29
52,9
20
6
94,3
322.000
104.7
357.000
90,1
8.750
32
65,2
22
440
500
KW
Btu
KW
Btu
%
Nm3/h
°K
KW
°K
Pa
Pa
70
100
70
°C
°C
°C
30
3
0,85
70
0,90
70
0,85
70
1,95
70
0,40
160
0,70
115
sec
min’
mBar
Pa
AT 10-8
1
230V
0,5
0,5
3,7
AT 12-9
1
230V
0,5
0,75
3,7
AT12-12
1
230V
0,5
1,1
4,0
AT 12-9
2
400V 3N
0,750
1,5
2,0
AT12-12
2
400V 3N
1,100
2,2
2,8
AT12-12
2
400V 3N
1,500
3,0
3,6
N°
50Hz ∼
KW
KW
A
4,0
4,7
7,5
3,6
5,0
6,5
A
40
II 2H3B/P
B22 – C12 – C32
IP
267
274
311
318
°C
%
Kg
Kg
2
500
2
540
4
450
122
122
133
135
-15 / +40
70
156
200
159
204
1
410
1
480
1
555
13,0
7,0
2,55
1,79
13,0
6,5
3,39
2,38
13,0
6,5
4,65
3,25
10,0
7,0
6,52
4,57
13,0
6,5
8,53
5,97
10,5
5,0
10,51
7,36
N°
mm/100
mBar
mBar
mBar
Nm3/h
3
Nm /h
35,0
18,0
0,98
1,97
3,88
0,68
1,38
2,72
0,0139
35,5
18,5
1,30
2,63
5,16
0,91
1,84
3,62
0,0185
35,5
18,0
1,78
3,60
7,07
1,25
2,52
4,94
0,0253
34,5
18,0
2,50
5,05
9,92
1,75
3,53
6,04
0,0356
35,5
18,0
3,27
6,60
12,97
2,29
4,62
9,08
0,0465
34,5
18,5
4,03
8,13
15,98
2,82
5,69
11,19
0,0573
mBar
mBar
Nm3/h
Kg/h
Litri/h
3
Nm /h
Kg/h
Litri/h
kg/s
20
References:
Atmospheric pressure 1013 mBar
Gas temperature 15°C
Atmospheric pressure 1013mBar
9
WIRING DIAGRAM
Schematic layout:
Heaters type 1-2-3
C
EVG1-II°
EVG1-I°
TR
SND
LM
FAN
N
J5
J12
II°
SF
F2
N
J6
L
LF
J1
IMT
J10
LL
J18
J15
LB
Electrical supply
single phase 230V 50Hz
I°
F1
J9
J13
RST
J16
MS
TA
J14
J2
J11
J17
J8
J4
J7
RSTR
VM
SE
IGN1
NA
NC
EA1
COM
EF
ION
PA
KEY:
SND
TR
LM
EVG1-I°
EVG1-II°
C
FAN
F1-F2
LF
LL
LB
RST
EF
PA
IGN1
Temperature control probe
Regulatory control thermostat(auto reset)
LIMIT thermostat (manual reset)
Gas solenoid valve
Gas solenoid min (two stage)
Capacitor / centrifual fan
Centrifugal fan
Line fuse
Green working light
High temperature indication
Lockout indication
Lockout reset
Flue venter
Differential pressure switch
Ignition transformer
EA1
ION
SE
IMT (*)
MS (*)
RSTR (*)
TA (*)
VM (*)
SF (**)
Ignition electrode
Ionisation probe
Control board
Fused isolator
Fire switch
Remote reset
Room thermostat
Fan switch
Second stage gas valve connection
(*) External to heater customer supply.
(**) Two stage only, External wiring customer
supply.
10
EVG1-I°
EVG1-II°
Heater type 2-3 up rated fan
TR
SND
LM
FAN
I°
J12
II°
SF
F2
J6
J9
J5
F1
LF
RT
J1
LL
CNT
J15
J10
LB
J13
J18
RST
MS
J16
F
TA
J14
J2
J11
J17
J8
J4
J7
RSTR
VM
SE
IGN1
NA
NC
EA1
COM
EF
ION
N
L
PA
Electrical supply
single phase 230V 50Hz
KEY:
SND
TR
LM
EVG1-I°
EVG1-II°
C
FAN
F1-F2
LF
LL
LB
RST
EF
PA
IGN1
EA1
Temperature control probe
Regulatory control thermostat(auto reset)
LIMIT thermostat (manual reset)
Gas solenoid valve
Gas solenoid min (two stage)
Capacitor / centrifual fan
Centrifugal fan
Line fuse
Green working light
High temperature indication
Lockout indication
Lockout reset
Flue venter
Differential pressure switch
Ignition transformer
Ignition electrode
ION
SE
RT
CNT
F
IMT (*)
MS (*)
RSTR (*)
TA (*)
VM (*)
SF (**)
Ionisation probe
Control panel
Relay fan motor
Fan contactor
Line fuse
Fused isolator
Fire switch
Remote reset
Room thermostat
Fan switch
Second stage gas valve connection
(*) External to heater customer supply.
(**) Two stage only, External wiring customer
supply.
11
EVG1-I°
EVG1-II°
Heater type 4
TR
SND
LM
FAN
I°
J12
II°
SF
F2
J6
J9
J5
F1
LF
RT
J1
LL
CNT
J15
J10
LB
J13
J18
RST
MS
J16
F
TA
J14
J2
J11
J17
J8
J4
J7
RSTR
VM
IMT
SE
IGN1
NA
NC
EA1
COM
EF
ION
N
L1
L2
L3
PA
Electrical supply
threephase 400V 50Hz 3N
KEY:
SND
TR
LM
EVG1-I°
EVG1-II°
C
FAN
F1-F2
LF
LL
LB
RST
EF
PA
IGN1
EA1
Temperature control probe
Regulatory control thermostat(auto reset)
LIMIT thermostat (manual reset)
Gas solenoid valve
Gas solenoid min (two stage)
Capacitor / centrifual fan
Centrifugal fan
Control fuse
Green working light
High temperature indication
Lockout indication
Lockout reset
Flue venter
Differential pressure switch
Ignition transformer
Ignition electrode
ION
SE
RT
CNT
F
IMT (*)
MS (*)
RSTR (*)
TA (*)
VM (*)
SF (**)
Ionisation probe
Control panel
Relay fan motor
Contactor fan motor
Line fuse
Fused isolator
Fire switch
Remote reset
Room thermostat
Fan switch
Second stage gas valve connection
(*) External to heater customer supply.
(**) Two stage only, External wiring customer
supply.
12
EVG1-II°
EVG2-II°
TR
EVG1-I°
EVG2-I°
Heaters type 5-6
SND
LM
FAN
I°
J12
SF
F2
RT
J1
LL
CNT
J15
J10
LB
II°
J6
J9
J5
F1
LF
J13
J18
RST
MS
J16
F
TA
J14
J2
J11
J17
J8
J4
J7
RSTR
VM
IMT
SE
IGN1
EA2
NA
NC
EA1
COM
IGN2
EF
ION
N
L1
L2
L3
PA
ALIMENTAZIONE ELETTRICA
TRIFASE 400V 50Hz 3N
KEY:
SND
TR
LM
EVG1-I°
EVG2-I°
EVG1-II°
EVG2-II°
FAN
F1-F2
LF
LL
LB
RST
EF
PA
IGN1
IGN2
Temperature control probe
Regulatory control thermostat(auto reset)
LIMIT thermostat(manual reset)
Gas solenoid valve 1
Gas solenoid valve 2
Gas solenoid min 1. (two stage)
Gas solenoid min2(two stage)
Centrifugal fan
Control fuse
Green working light
High temperature indication
Lockout indication
Lockout reset
Flue venter
Differential pressure switch
Ignition transformer 1
Ignition transformer 2
EA1
EA2
ION
SE
RT
CNT
F
IMT (*)
MS (*)
RSTR (*)
TA (*)
VM (*)
SF (**)
Ignition electrode 1
Ignition electrode 2
Ionisation probe
Control panel
Relay fan motor
Contactor fan motor
Line fuses
Fused isolator
Fire switch
Remote reset
Room thermostat
Fan switch
Second stage gas valve connection
(*) External to heater customer supply.
(**) Two stage only, External wiring customer
supply.
13
REMOTE CONTROL CONNECTIONS
Connection to CP2A
Key:
B
BK
BN
GR
G
K
Blue
Black
Brown
Grey
Green
Pink
M
O
P
R
W
Y
Magenta
Orange
Purple
Red
White
Yellow
This wiring to be completed by the installer
READ THE INSTRUCTION MANUAL BEFORE
PROCEEDING WITH THE INSTALLATION
INCORRECT WIRING WILL DAMAGE THE
ELECTRICAL CONTROL PANEL
THIS HEATER IS NEUTRALLY SWITCHED
ENSURE THE WIRING IS CORRECT TO THE
DIAGRAMS PROVIDED
14
OPERATION
To switch OFF fan
• Set ON/STANDBY switch to STANDBY
To switch ON the heater
• Switch the fused isolator switch ON (supply
customer)
• Switch the heater ON/OFF selector to “ON”
• Turn the thermostat to the desired temperature
• The heater will start automatically
Stop
• Turn the selector switch to STOP
IF HEATER IS TO BE SWITCHED OFF FOR A LONG
PERIOD
• Set ON/STANDBY switch to STANDBY
• Isolate at mains electrical supply
• Isolate the gas supply
To switch OFF the heater
• Turn the thermostat to its lowest temperature setting
or alternatively switch the heater ON/OFF selector
switch to OFF
• The burner will switch off but the fan will continue to
operate for 3 to 4 minutes to cool the combustion
chamber before stopping
• Finally switch the fused isolator to OFF
WARNING! UNLESS IN AN EMERGENCY
Never stop the heater by switching off at the mains
isolator. The residual heat accumulated in the heat
exchanger may trigger the LIMIT safety device
resulting in the need to reset manually.
If this is repeated it will damage the heat exchanger
and will invalidate the warranty on the heater.
To switch ON fan only
• Switch the fused isolator to ON
• Set ON/STANDBY switch to ON
• Set VENT/HEAT switch to VENT position
• The fan only will run
VERSION SINGLE STAGE
In the single stage version the heater has a standard maximum heat output and a fixed air flow capacity the heater can
be operated manually via a switch or automatically by a remote thermostat.
VERSION TWO STAGE
In the two stage version the heater has a two stage high low gas valve and can be operated in either high fire or low fire
but with a fixed air flow capacity the heater can be operated manually via a switch or automatically via a remote
thermostat.
SERVICING
•
•
•
A safe working platform giving good access to the
heater is required.
Clean all accessible surfaces including the outside of
the heat exchanger by removal of the fan assembly and
the louvres. Check for panel damage and that all
fasteners are present and secure.
Visually check all electrical wiring for signs of damage,
possibly through contact with hot surfaces, check
conduit for signs of chaffing and for security . Check all
terminals are secure and free from escaped / stray
conductor strands
Switch the fused isolator switch ON (supply
Turn the thermostat to its lowest temperature setting
or alternativly switch the heater ON/OFF
The burner will switch off but the fan will continue to
operate for 3 to 4 minutes to cool the heater.
WARNING!
It is a requirement that only qualified personnel are
allowed to carry out installation commissioning or
servicing. In addition only spare parts recommended by
the manufacturer may be fitted, and the installer should
provide a list of recommended spare parts that are
available through the manufacturer or his agent.
Before commencing any maintenance or servicing work
the heater must be shut down and allowed to cool, and
have the gas and electric supplies to it turned off at the
supply cock and isolator respectively.
CLEAN EXTERNAL PANELS
This cleaning should only be carried out with damp
cloths with soap and water. In If there are stubborn
stains dampen The cloth with a 50% mixture of water
and white spirit.
After cleaning dry the surfaces carefully.
Always test for gas soundness after completing any
service work particularly if this has necessitated
the removal and / or replacement of gas carrying
components
CLEANING
Filters should be cleaned regularly as required.
It is advisable that routine inspections are carried out on
a frequent basis, servicing must also be carried out
regularly, and in accordance with the manufacturers
recommendations i.e. at a maximum interval of one
year. In certain applications the frequency of servicing
will have to be increased, this to a large extent is
governed by the working environment, and both the
manufacturer and the installer will be able to offer
further advice.
15
HEATER INDICATOR LIGHTS
If a fault should occur with the heater the lights situated
at the right hand side of the heater will be illuminated
indicating the fault
• Red Lockout indication (1).
This will be illuminated if the heater has gone to
lockout due to the loss of flame sensing by the flame
probe situated in the burner assembly in order to reset
the heater the RESET Button (2) should be pressed (if
fitted with remote controls the remote reset button will
reset this switch).
• Yellow overheat indication (3).
This will be illuminated if the heater has exceeded the
temperature set on the thermostat. The thermostat will
shut down the burner until the fan(s) have cooled the
chamber sufficiently and the burner will re light.
If the yellow light is flashing this means that the heater
has gone to overheat and the LIMIT thermostat has
operated and shut down the burner The heater will not
re light until the LIMIT (4) has been reset this can be
done by removing the plastic cap covering the reset
button and pushing the reset replace cap
The cause of the overheat should be investigated
RECEIPT OF PRODUCT AND TRANSPORT
Delivery & pre installation checks
The heater is supplied wrapped in heavy duty
protective polythene, mounted on a pallet. On receipt
of the heater, the following checks should be carried
out:
a) The model is as per order
b) That it is undamaged
c) That it is suitable for the gas supply and pressure
d) That it is suitable for the electrical supply
If any of these points are not satisfied then contact
should be made with the Sales Office at Benson
Heating In the case of claims for damage this must
be reported in writing within 24Hrs of delivery, in
order to comply with insurance criteria
WARNING
The instruction manual is an integral part of the
equipment and so, after the packaging has been
removed, make sure that it has been collected and
stored safety.
When moving the heater ensure that the
equipment used is capable of lifting and
supporting the weight of the heater
When lifting by fork truck ensure that the
forks support the weight
16
DIMENSION AND WEIGHT
Type 1 – 2 – 3 – 4
Type
A [mm]
B [mm]
C [mm]
D [mm]
E [mm]
F [mm]
G [mm]
H [mm]
J [mm]
K [mm]
L [mm]
∅1 [mm]
∅2 [mm]
∅ [bsp]
Nett weight [kg]
17
(1) female
(2) male
Note: Heater type 5 has two centrifugal fans.
20
1
665
745
435
563
140
132
132
710
335
910
1225
100 (1)
100 (1)
½
122
2
745
745
515
563
140
132
132
790
415
910
1225
100 (1)
100 (1)
½
133
3
925
745
695
555
140
132
132
970
595
910
1225
100 (1)
100 (1)
½
156
4
1170
793
940
510
185
115
132
1215
840
960
1273
100 (2)
150 (2)
¾
200
Type – 5 – 6
Type
A [mm]
C [mm]
H [mm]
J [mm]
∅ [bsp]
Nett weight [kg]
18
male
male
20
5
1720
1300
1640
1200
¾
267
6
1960
1540
1885
1440
¾
311
INSTALLATION
It is a requirement that only qualified and competent
personnel may undertake installation commissioning
and servicing of Heaters.
Where the passage of cold air causes problems (eg by
entrances, loading bays etc) it is considered favourable
if the heater is positioned so as the discharge towards
or across the cold air source from a distance from 1.5m
- 6m dependent upon the size of the entrance and the
air throw characteristics of the heater. On exposed
walls heaters should be positioned so as to discharge
towards, or along the length of the exposed wall.
WARNING
All of the basic criteria must be satisfied prior to
commencing
installation
and
commissioning,
additionally, the Unit Heater must be positioned and
installed so as to comply with all the relevant standards
and guide lines as well as meeting national and local
fire regulations and insurance criteria, especially if it is
proposed that the heater is to be installed within a
special risk area (e.g. proximity to where petrol engined
vehicles are stored or parked, where cellulose spraying
takes place, where woodworking machinery is
operated, etc,).
CAUTION
Ensure that the gas service to the appliance carries the
correct gas type and that the supply pressure is in
accordance with the supply type and pressure stated on
the appliance data plate.
Installation, commissioning, and servicing must only be
carried out by appropriately qualified and competent
persons.
Indirect fired heaters must not be located in hazardous
areas. However, it is permissible for the heater to
supply air to such areas. The heater must not be
installed within an environment where there is a high
concentration of chlorides, fluorides, salts, or other
aggressive or volatile chemicals/compounds.
Nor should the heater be positioned where the burner
could be adversely affected by high winds or draughts.
WARNING
Unauthorised modifications to the appliance, or
departure from the manufacturers guidance on
intended use, or, installation contrary to the
manufacturers recommendations may constitute a
hazard.
NOTE
To ignore the warning and caution notices, and to
ignore the advice from the manufacturer on installation,
commissioning, servicing, or use, will jeopardise any
applicable warranty, moreover, such a situation could
also compromise the safe and efficient running of the
appliance itself, and thereby constitute a hazard.
The installation of the appliance must meet all the
relevant European, National, and local criteria. Prior to
installation the following points should be considered:
The heater must be installed so that it is level. Supports
for the heater must be sufficiently robust to withstand
the weight of the heater and any ancillary equipment.
Any combustible material adjacent to the heater or flue
system must be so placed or shielded so that its
surface temperature does not exceed 65ºC
The location chosen for the heater must allow for
the fitting of an effective flue system.
The heater must be installed so that it is level, supports
for the heater must be sufficiently robust to withstand
the weight of the heater and any ancillary equipment
Any combustible material adjacent to the heater or flue
system must be so placed or shielded so that its
o
surface temperature does not exceed 65 C. Generally a
free blowing heater should be located at a height
(measured from floor level to the base of unit)
a) The position of the heater for the optimum efficient
distribution and circulation of warm air
b) The position of the heater relative to the route of the
flue
c) The position of the heater relative to the supply of
gas
d) The position of the heater relative to the electrical
services, wiring routes, and if appropriate, any
additional controls.
e) The position of the heater relative to the supply of
fresh air
f) The position of the heater relative to potential
stratification / circulation problems, which generally
occur at higher levels and which may be overcome
through the provision of a suitable de-stratification
unit.
g) The position of the heater relative to service and
maintenance requirements
The location chosen for the air heater must allow for the
fitting of an effective flue system. It must also allow
adequate clearance for the air supply, return air
circulation, gas supply, electrical supply and also
provide good service access.
Suspended free blowing Unit Heaters are at their most
effective when located as close to the working area as
possible. However care should be exercised to avoid
directing the discharged air directly onto the occupants
of the area to be heated.
CAUTION
The heater must not be installed within an area where
the conditions are unsuitable, e.g. where the
atmosphere is highly corrosive, has a high degree of
salinity, or where high wind velocities may affect burner
operation. Suitable protection should be provided for
the appliance when it is located in a position where it
may be susceptible to external mechanical damage
from; for example, fork lift trucks, overhead cranes etc.
Where the passage of cold air causes problems (eg by
entrances, loading bays etc) it is considered favourable
if the heater is positioned so as the discharge towards
or across the cold air source from a distance from 1.5m
- 6m dependent upon the size of the entrance and the
air throw characteristics of the heater. On exposed
walls heaters should be positioned so as to discharge
towards, or along the length of the exposed wall.
19
INSTALLATION CLEARANCES
min. 700
For the correct operation of heater and for maintenance purposes the following minimum clearances around the heater
should be observed
*
min. 700
✴
Minimum200 mm type1 – 2 – 3 – 4
Minimum 700 mm type 5 – 6
Heater with warm air duct air inlet from below heater only
min 400
min. 200
Heater with warm air duct air inlet from rear and below heater.
min 400
min. 400
20
EXAMPLES OF INSTALLATION
Further examples
L
INSTALLATION:
• Internal installation
• Mounted on wall brackets (1)
• Ducted warm air outlet (2)
• Open return air or ducted (3) from inside the building
• Filter (4) Air Inlet casing (5)
Type
1÷3
4÷6
5
4
2
1
L
360
410
3
1635
5
4
2
INSTALLATION:
• Internal installation
• Mounted on flat surface or beam (6)
• Ducted warm air outlet (2)
• Open return air or ducted from rear (3)
• Filter (4) Air inlet casing (5)
3
6
L
L1
INSTALLATION:
• Internal installation
• Mounted on wall brackets (1)
• Ducted warm air outlet (2)
• Ducted return air from room and external (3)
• Filter (4) Air inlet casing (5).
• Air damper (7)
• External rain proof cowl (8)
Type
1÷3
4÷6
L
360
410
5
3
4
2
7
7
L1
100
50
1
3
1635
Filters, Air dampers, rain cowl, support brackets are available as accessories .
21
4
8
ACCESSORIES
Available accessories:
NO.
1
2
3
4
5
6
7
8
9
10
11
12
13
DESCRIPTION
Conical duct connection
Horizontal louvres
Fire damper
Air discharge damper
Air inlet damper
Air filter
Rain proof inlet cowl
Damper motor
Manual control for damper
Control arm
Wall bracket
Support beam
Remote controller
TYPE
1
2
3
4
5
6
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
z
22
GAS CONNECTION
•
Conection of the heater to the gas supply,
whetherNatural Gas or L P G , must be carried out
in compliance with the installation laws and by
qualified personnel. The warm air heater is factory
set to work with (G20) Natural Gas.
A (G31) Propane kit is also available
•
Before connecting the heater it is necessary to make
sure that.:
• The correct type of gas for which the equipment has
been set up for is available.
• The gas pipes are clean and free from debris .
The gas supply and meter are capable of delivering
the required volume of gas to ensure the correct
burner pressure can be achieved See TECHNICAL
DATA
The diameter of the pipework from the isolating cock
to the burner must not be less than the diameter of
the connection into the multiblock .
An approved gas jointing compound must be
used on all joints and unions and the system
purged and tested for soundness prior to final
connection
Gas Installation
1.
Threaded gas pipe connector Male 1/2” BSP
thread on (type 1-2-3) and 3/4” on (type 4-5-6).
2.
Pressure stabiliser* (Required
correct gas pressure at valve).
3.
Filter* (Advised to prevent impurities which may
be present in the gas line from entering the gas
valve and also to permit simple inspection and
maintenance).
4.
Isolating Cock*: Each heater supply must be
fitted with a separate isolating cock
positioned adjacent to and upstream of the
union which must be sited outside the heater
0
the cock should be of the 90 turn type should
be clearly marked OPEN/CLOSED and should
be installed so as to fall to the closed
position.
to
ensure
5. Gas pipe*
(*)Customer Supply
WARNING!
As there have been recorded instances of the
deposition of copper sulphide dust within the valves and
orifices of gas appliances as a direct result of a reaction
between the hydrogen sulphide contained in some
natural gasses and copper pipe we recommend that the
heater(s) should not be connected to any natural gas
pipe distribution system which utilizes copper pipework,
including final connections. Instead steel pipework
should be used throughout.
In the event that it is impractical to use steel pipework
or where installers are obliged or insist on using
elements of copper pipework within the installation then
we strongly recommend that the gas supplier be
consulted as specific conditions and requirements may
be necessary.
WARNING!
When LPG supply is used it is advisable to install a
first stage pressure reducer close to the LPG tank to
reduce the pressure to 1.5 Bar and a second pressure
reducer near to the heater installation to bring the
pressure down fron 1.5bar to 40 mbar max. A third
reducer (2) mounted in proximity to the heater ensures
the correct pressure is provided.
Note
Reference to The Institute of Gas Engineers
publications utilisation Proceedures IGE/UP1 and
IGE/UP2 togethrer with reference to BS6891 is strongly
advised
To prevent any problems which could arise due toloss
of pressure it is advisable to install a minimum pressure
switch to shut down the heater in the event of gas
pressure failure.
23
FLUE AND COMBUSTION OPTIONS
Room sealed unit heaters are suitable for installation with the following flue configurations : B22 - C12 - C32 .
Option B22
In this configuration the heater is connected to a single
flue pipe to discharge the products of combustion
outside the building either through the roof or through a
wall
The combustion air is taken from inside the room
•
•
•
•
•
•
The flue pipe should be metal smooth bored pipe
with a diameter of not less than the flue spigot
connection on the heater
All joints should be sealed
It must be properly secured so as to remain stable
at all times
It must have a wind shielded and rain proof terminal
The flue should not exceed the length limits
indicated in the following pages
There must be adequate ventilation in the room as
per current legislation.
Option C12
•
•
In this configuration the heater is connected by two
pipes, One discharging the products of combustion and
the other bringing the combustion air from outside the
building in which the heater is located
•
•
The outlet must be through the wall and may be made
with two separate pipes or with concentric pipes
•
•
The flue pipe and combustion air inlet should be
metal smooth bored pipe with a diameter of not less
that both the flue and combustion spigot
connections on the heater
All joints should be sealed
It must be properly secured so as to remain stable
at all times
It must have a wind shielded and rain proof terminal
The flue should not exceed the length limits
indicated in the following pages
There must be adequate ventilation in the room as
per current legislation
Option C32
•
•
In this configuration the heater is connected by two
pipes, One discharging the products of combustion and
the other bringing the combustion air from outside the
building in which the heater is located
•
•
The outlet must be through the roof and must be made
with concentric pipes
• The flue pipe and combustion air inlet should be
metal smooth bored pipe with a diameter of not less
that both the flue and combustion spigot
connections on the heater
All joints should be sealed
It must be properly secured so as to remain stable
at all times
It must have a wind shielded and rain proof terminal
The flue should not exceed the length limits
indicated in the following pages
The following pages show installation diagrams of the above configurations.
24
B22: Single pipe flue to outside wall or roof terminal. Combustion air from inside
building
L1
Ø100
MIN. 400
L2
MAX 500
Ø100
MIN 400
INSTALLATION DISTANCES FOR FLUE PIPE:
HORIZONTAL FLUE
TYPE UNIT
L1 MIN.
L1 MAX.
1
m
1,00
5,00
2
m
1,00
5,00
3
m
1,00
5,00
4
m
1,00
5,00
5
m
1,00
5,00
6
m
1,00
5,00
•
•
•
•
VERTICAL FLUE
L2 MIN.
L2 MAX.
1,00
10,00
1,00
10,00
1,00
10,00
1,00
10,00
1,00
10,00
1,00
10,00
Only manufacturers recommended flue must be used
When designing the flue consideration should be made for entrapment and disposal of any condensate
Each bend corresponds to between 0,8-1 meter of horizontal pipework
The flue installation must comply with all the relevant regulations regarding height and position from all openings.
25
C12: Horizontal flue installation twin pipe and concentric flue terminals.
L1
*
Ø100
MIN. 400
✴
100 mm type 1 – 2 – 3
150 mm type 4 – 5 – 6
MAX 500
L2
Ø150
*
Ø100
MIN. 400
MAX 300
INSTALLATION DISTANCES FOR FLUE PIPE:
TWIN PIPE SYSTEW
TYPE UNIT
L1 MIN.
L1 MAX.
1
m
1,00
2,50
2
m
1,00
2,50
3
m
1,00
2,50
4
m
1,00
2,50
5
m
1,00
2,50
6
m
1,00
2,50
•
•
•
•
HORIZONTAL CONCENTRIC TERMINAL
L2 MIN.
L2 MAX.
1,50
2,50
1,50
2,50
1,50
2,50
1,50
2,50
1,50
2,50
1,50
2,50
Only manufacturers recommended flue must be used
When designing the flue consideration should be made for entrapment and disposal of any condensate
Each bend corresponds to between 0,8-1 meter of horizontal pipework
The flue installation must comply with all the relevant regulations regarding height and position from all openings
26
C32 Concentric vertical roof terminal
Ø150
L1
Ø100
*
✴
100 mmtype 1 – 2 – 3
150 mm type 4 – 5 – 6
INSTALLATION DISTANCES FOR FLUE PIPES:
TYPE
UNIT
1
2
3
4
5
6
m
m
m
m
m
m
•
•
•
•
VERTICAL ROOF TERMINAL
L1 MIN.
0
0
0
0
0
0
L1 MAX.
10,00
10,00
10,00
10,00
10,00
10,00
Only manufacturers recommended flue must be used
When designing the flue consideration should be made for entrapment and disposal of any condensate
Each bend corresponds to between 0,8-1 meter of horizontal pipework
The flue installation must comply with all the relevant regulations regarding height and position from all openings
27
ELECTRICAL PANEL AND CIRCUIT BOARD
Panel illustrated is fitted to type 5 and 6.
1.
2.
3.
4.
5.
6.
7.
Lockout reset
Red lockout indication light
Yellow temperature indication light
Green operating light
Flame control circuit
Remote connection
Line fuse 3.15 Amp
8.
9.
10.
11.
12.
13.
14.
Control box cover
Differential pressure switch
Main fuse (type 4-5-6, 2-3 up rated fan)
Neutral fuse (type 4-5-6)
Earth connection (type 4-5-6, 2-3 up rated fan)
Contactor (type 4-5-6, 2-3 up rated fan)
Overload protection (type 4-5-6, 2-3 up rated fan)
ELECTRICAL CABLE CONNECTIONS
Only cable sockets provided should be used
when wiring heater .
Ensure cables are properly secure
Care should be taken to ensure that the cables
are not exposed to hot surfaces.
ELECTRICAL CONNECTION
damage from being sustained to the heater or its
controls (ie: during servicing).
Claims for damage will not be considered if they
have resulted from incorrect wiring or the incorrect use
of the heater.
Each heater requires a permanent 230V 50Hz 1ph
(415/3/50Hz, Types 5 6 ) electrical supply, which must
be wired through a Fused Isolator fitted with a fuse of
the correct rating.
The correct supply connection points for the live,
neutral, and earth are clearly indicated on the wiring
diagram mounted inside the wiring box cover.
Wiring diagrams are also detailed within this manual.
The electrical supply isolator should be mounted
adjacent to the air heater in an easily accessible
position to allow for servicing isolation, or emergency
shut off.
The heaters are supplied with the electric panel fitted
and pre wired Connection is required to
• The mains electrical supply
• A room thermostat
• Or accessories such as a remote control panel.
All electrical wiring and connections must be in
accordance with the relevant European, National, and
local regulations as well as to IEE Standards.
Ensure that the Electric and gas supplies are
turned off before any electrical work is carried
out on the heater.
Also ensure that wiring cannot make contact
with any metal surfaces liable to be subject to
high temperatures, and where insulation of the
wiring could be impaired as a result of such
contact.
All the heaters must be earthed.
Ensure that the mains isolator is turned OFF
before undertaking any electrical on the
heater. Access to the electrical panel is
gained by opening the right hand heater side
panel.
The main electrical supply must not be switched
off or disconnected as a method for stopping the
heater, the exception to this is in the event of an
emergency, or when the heater has been
allowed to cool sufficiently to prevent any
28
Any
ancillary
electrical
items
e.g.
room
thermostats, time switches, remote panels etc,
must be wired into the heater electrical circuit in
accordance with the diagrams provided.
When external controls operate to switch the heater
OFF, power to the heater should remain to allow the
fan to continue to operate to sufficiently cool the
heater thereby preventing damage to the heat
exchanger.
The cover to the electrical panel can be removed by
undoing the screws which secure it to the panel. A copy
of the wiring diagram is affixed to the inside of the
cover.
Ensure that all connections are secure and that
there are no loose strands which could bridge
across the terminals.
One electrical panel per heater is required, unless
heaters are specified for multiple heater control
applications. On no account should more than one
heater be connected to a single time switch or
thermostat. The only exception to this is when a control
panel suitable for multiple heater applications is
supplied by the manufacturer, in which case the wiring
diagram supplied with the control panel should be read
in conjunction with the existing wiring diagram.
WARNING!
THESE HEATERS
SWITCHED.
ARE
NEUTRALLY
ELECTRICAL TABLE
Type Electrical
supply
Power
motor
Fuse (1)
Thermal
Relay
Power up
rated fan
motor
(kW)
Fusibili (1) Relay up
up rated
rated
motor
motor
(A)
(A)
Live
Cable (2)
Earth
Cable (2)
(kW)
(A)
(A)
(mm2)
(50Hz∼)
1
230V
0,50
6,3
N.A.
0,50
6,3
N.A.
1,5
2
230V
0,50
6,3
N.A.
0,75
10
3,7÷5,5
1,5
3
230V
0,50
10
N.A.
1,1
12
5,5÷8,0
1,5
4
400V 3N
0,75
10
1,8÷2,6
1,5
10
2,6÷3,7
1,5
5
400V 3N
1,1
10
2,6÷3,7
2,2
10
3,7÷5,5
1,5
6
400V 3N
1,5
10
2,6÷3,7
3,0
12
5,5÷8,0
1,5
(1) Included with the heater
(2) The supply cable size should ensure a fall in voltage of less than 5% over a length of 30 meters
(mm2)
1,5
1,5
1,5
1,5
1,5
1,5
DUCT CONNECTION
The heater is supplied with a duct spigot fixing points and dimensions below.
15
435
515
695
940
1300
1540
232
272
362
242
332
392
520
1
2
3
4
5
6
N°of
fixings
6+2
6+2
6+2
10+2
10+2
10+2
244
B
15
244
A
B
464
Type
B
16
1
16
Ø7.5
29
Important:
• A gasket should be provided between the heater
flange and the ductwork (not supplied)
• In order to prevent the transmission of vibrations to
the ducting a suitable flexible joint is advised
• The ductwork should be suitably supported through
out the installation.
•
A
29
The total resistance in both the inlet and supply
ducting should not exceed that given in the
TECHNICAL DATA section of this manual .
The heater should always be connected to
ductwork, and not operated as a free blowing unit
only a suitably qualified and competent person
should size the ductwork.
29
RETURN AIR CONNECTIONS
The heater is supplied with 2 return air connecctions one at the rear and one underneath:
a. Return air from direction “A”;
b. Return air from direction “B”;
c. Return air from both direction “A” and “B”.
A
The heater is supplied with a grille at the rear and a
blank panel underneath, both the grille and panel are
interchangable the fixing points and dimensions of the
return air plenum are detailed below.
B
15
B
1
2
3
4
5
6
365
445
625
870
1230
735
335
415
595
840
1200
1440
N° of
fixings
4
4
4
4
4
6
15
539
A
510
Type
A
15
32
M6
30
B
30
PROTECTION
To prevent any accidental damage or contact with the moving parts of the heater ensure all grilles and panels are
securely in place
PRE COMMISSIONING CHECKS
Once the equipment has been installed, and before it is
started up, check the following:
• All the safety conditions have been observed
• The equipment has been suitably positioned
• That the free area around the machine has been
respected
• The gas connections have been properly carried out
• The exhaust and intake pipes have been correctly
installed
• All the taps for the various circuits are open
• All the electrical connections have been properly
carried out
The following pre-commissioning checks should be
undertaken, having first ensured that the gas and
electrical supplies are turned off.
• Check that all panels and fasteners are secure and
in place.
• Check that the heater is mounted safely.
• Check that the flue is sealed, secured, and
adequately supported.
• Check that the fan is free to rotate, that the fan
motor is secure and that the guards and fan
assembly are all in place and properly secured
• Check that the heater is installed so that it is not
tilted and remains square.
• Check that the outlet duct resistance is compatible
to the data plate .
The may be fumes and odours the first time
the equipment is started up, caused by the
evaporation of liquid protecting the heat
exchanger in storage; this is normal and will
disappear after a short time of working. It is
advisable to properly ventilate the room.
30
INITIAL START UP
Before each attempt at ignition
necessary to wait at least 10 seconds.
VENTILATION
• Switch on mains supply to the equipment
• Set On/ Standby switch to ON
Set the remote control panel switch to VENT check that
fans rotation is correct
it
is
When the burner has ignited check the manometer and,
adjust gas pressure setting to pressure indicated on
data plate, adjust by turning the solenoid valve screw
on gas valve.
• Check the gas consumption reading corresponds
with that indicated in the TECHNICAL DATA
section.
• Set on/standby switch to ‘standby’. When heater is
sufficiently cool Isolate electrical supply Isolate gas
supply. Remove the manometer and ensure the
screw at the test point is tightened to avoid any gas
leaks
• Open the gas isolating cock Switch on electrical
supply. Set the room thermostat to the desire
temperature. The heater is now ready for operation.
HEAT
Set the remote control panel to HEAT
Set the room thermostat to the desired temperature
The flue venter will start, activating the differential
pressure switch
After a short period ignition takes place After one
minute the air flow fan will start
When desired room temperature is reached the burner
will stop the fan will overrun for approximately 3-4
minutes.
•
•
•
IGNITION
Connect the manometer on the pressure test point
on the gas manifold
• Set mains isolator to On
• Open gas isolator cock
• Set the on/standby switch to ‘On’
• Set heat/vent switch to Heat
• Set the room thermostat to the desired temperature
• Reset any lockout in the system as indicated by the
red or yellow lights.
The flue venter will start up activating the differential
pressure switch.
The heater will pre purge the combustion chamber the
electronic control box will supply the ignition electrode
and the gas valve simultaneously.
If the gas line has not been correctly purged ignition
may not take place at the first attempt resulting in
lockout of the burner. Reset button and repeat.
•
WARNING!
The heater must only be operated with the burner
compartment door(s) closed
STOPPING
To stop the heater using only the room thermostat Set it
to the minimum temperature. Fan will stop after about
3-4 minutes. If required, switch off the mains current at
the isolator.
WARNING
If Heater is to be switched Off for a Long Period set
ON/STANDBY switch to STANDBY.
Isolate at mains electrical supply
Isolate the gas supply
Model SIT 843 (TWO STAGE)
Model SIT 840 (SINGLE STAGE)
PM
PV
RP
RP1
RP2
Main inlet pressure point
Head pressure test point
Pressure adjusting screw
Cross cut screw low fire adjuster
Hexagonal screw high fire adjuster
31
GAS CONVERSION
The heaters are supplied ready for use with (G20),Natural Gas as per the table below LPG Conversion kits are available
from the manufacturer:
Natural Gas (G20)
TYPE
Number of injectors
Diameter of injectors
Gas supply pressure
Head pressure max
Head pressure min (two stage)
1
1
410
2
1
480
3
1
555
13,0
7,0
13,0
6,5
13,0
6,5
4
2
500
20 mBar
10,0
7,0
5
2
540
6
4
450
N°
mm/100
13,0
6,5
10,5
5,0
mBar
mBar
Before converting the heater to LPG ensure that the gas supply is isolated conversion should be carried out as described
in the following section .
INSTRUCTIONS FOR CONVERSION TO PROPANE (G31):
1. Change injectors
2. Adjust to the correct gas inlet pressure
3. Adjust to the correct head pressure
4. Fit primary air diaphram (if required)
5. Change adhesive label supplied with kit indicating correct gas type
6. Ensure settings are correct as per the manual and data plate.
CHANGE INJECTORS:
To change injectors:
Unscrew the natural gas injectors and replace them with the correct size injectors for propane as shown in the table
below:
Propane Gas (G31)
TYPE
Number of injectors
Diameter of injectors
1
1
250
2
1
280
3
1
335
4
2
285
5
2
320
6
4
255
N°
mm/100
Replacing injectors single manifold (type 1-2-3-5)
Replacing injectors twin manifold (type 4-6)
Check the size stamped on the side of the
injector is correct to the data in the manual.
label completely test for gas soundness on
completion.
Ensure that the aluminium washers supplied for
types (5–7) are fitted when changing the
injectors.
Ensure that the new injectors are correctly fitted
in the manifold and are gas tight. When the
conversion is complete afix the adhesive label
supplied with the kit indicating the correct gas
pressure on to the manifold covering the existing
32
GAS PRESSURE SETTINGS
To regulate the gas inlet pressure :
•
Connect a manometer to pressure test point (PM)
•
Ensure that gas supply pressure is sufficient as detailed the table in the manual provided :
To regulate the head pressure at the injectors:
•
Connect a manometer to pressure test point (PV)
•
Adjust the pressure untill it is correct to the data supplied in the following table:
VERSION SINGLE STAGE
Propane Gas (G31)
TYPE
Gas inlet pressure
Head pressure max
Head pressure min (two stage)
1
VERSION TWO STAGE
2
3
4
5
6
34,5
18,0
35,5
18,0
34,5
18,5
37
35,0
18,0
35,5
18,5
35,5
18,0
mBar
mBar
mBar
Warning gas inlet pressure should not exceed 60 mBar.
SINGLE STAGE
Gas valve regulatiion Propane G31:
For operation with propane G31 the pressure regulation
screw on the valve must be excluded.
To exclude the regulation screw on the gas valve
the following proceedure should be carried out:
• Remove the plastic cap
•
•
Turn the screw RP clockwise to the bottom
Replace the plastic cap and reseal with paint
For heaters equiped with two gas valves it will be necessary to exclude both valves .
TWO STAGE
Gas valve regulation Propane G31 :
Gas valve head pressure setting high fire Propane G31:
Remove the plastic cover from the adjuster RP1 RP2
With a screw driver hold the adjuster RP1 stationary
and using a spanner, screw adjuster RP2 clockwise to
the bottom of the thread until the correct pressure
according to the data plate is achieved .
When setting the gas pressure for propane high fire
(second stage ) contact SF should be closed the high
fire pressure adjusting screw on the gas valve must be
excluded.
Connect a manometer on test point PV
33
Gas valve head pressure setting low fire Propane G31:
When setting the gas pressure for propane low fire (first
stage) contact SF should be open. The low fire
pressure should be adjusted to the settings shown on
the data plate and the data in the manual provided by
adjusting screw RP1
Clockwise increases the pressare. Anti clockwise to
decrease the pressare. On completion replace the
plastic cover and seal with paint.
Remove manometer ensuring that the test point screw
is gas tight.
For heaters equiped with two gas valves it will be necessary to exclude both valves .
Assembly of primary air diaphragm:
Diagram showing the fitting of a primary air
diaphragm to single burner manifold (1-2-3-5)
Diagram showing the fitting of a primary air
diaphragm for a two burner manifold type (6)
Warning the diaphragm plates should only be used when using propane gas G31.
Gas conversion adhesive label:
Once the heater has been converted to propane ensure that the correct label is fitted to the burner overtop of the factory
fitted one covering it completely. It is recommended that the diameter of the nozzles be checked also that the pressure
corresponds to that shown on the data plate provided
Ensure that all of the additional gas components are correct for the installation (including storage tank, pipes and
pressure valves etc
Ensure that the pressure regulators are sealed after carrying out the conversion.
Gas inlet pressure must not exceed 60 mbar at the gas valve inlet.
THERMOSTAT
• LIMIT THERMOSTAT (LM)
When due to a fault the air temperature near the sensor
reaches exceeds the set value and reaches (100°C),
the yellow indicator light will flash and the burner will
shut down The overheat limit switch will have to be
manually reset
The heater is supplied with thermostats to control the
FAN operation and LIMIT functions.
• FAN OPERATION (SND)
When the air near the sensor SND reaches the set
temperature (30°C) which is approximately 30 seconds
after ignition the electrical contact closes and starts the
fan.
When the air temperature close to the sensor drops
below the set temperature (30°C) and about 3-4
minutes after the burner switches off the fan will stop.
This prevents cold air flows when the burner starts and
stops.
Fan control SND TR function is connected in
parallel through the control box to the fan operation
SND
• FAN CONTROL THERMOSTAT (SND - TR)
If the air reaches the set temperature due to a fault in
the air circulation (SND – TR) thermostat (70°C), will
shut down the burner and the yellow light on the front of
the heater will illuminate. Once the heater has
sufficiently cooled down the thermostat will reset and
the light will go out. Continual operation should be
investigated.
34
FAN
To check electrical absorption of the motor proceed
as follows:
• Insert the ammeter on a phase of the general supply
line
• Set the appliance to summer ventilation, so as to
exclude all other equipment (burner and auxiliary
parts)
Read the absorption figure on the ammeter and
compare it with the plate data for the motor shown in
the TECHNICAL DATA chapter.
The driven variable pitch pulley drive and fixed fan
pulley are factory pre set and are suitable for most
applications.
The fan speed can be adjusted on the variable speed
pulley to allow for variations in duct resistances
inclusion of filters etc.
If will be necessary to check that the temperature rise
across the heater is within the tolerance shown in the
technical data .
On types 4-5-6 Three Phase heaters, fan rotation
should be checked prior to first ignition of the unit. It
may be necessary to adjust the motor pulley to achieve
correct motor running current as motor plate.
Regulation of the variable pulley on the motor
1.
2.
3.
4.
5.
6.
Slacken the belt tension by unscrewing
screw (5)
Remove the belt (1)
Loosen grub screw (3) of the mobile part of
pulley with a hexagonal spanner (2)
Rotate the mobile part of the pulley so as to
obtain the pitch line diameter required
Lock the grub screw (3) tightly at the hub
hollow
Mount and tighten the belt (1)
CONTROL
To ensure that the heater is working correctly certain
criteria need to be checked . Start up heater and check
the following
•
•
•
•
Check that the fan starts approximately 30 seconds
after ignition of the burner.
•
When the heater is at its full efficiency after about 20
minutes the following checks should be made:
•
•
•
•
•
•
Check that the horizontal fins are correctly set so as
to give the optimum heating performance and the air
flow is sufficient to cool the heat exchanger. ensure
where vertical fins are installed they are also open
and not restricting the air flow.
Check that there are no gas leaks
Check that the gas rate is correct using a meter.
Check injector pressure is correct.
Check temperature rise is correct to data plate.
•
•
•
•
•
35
Check the operation of the control and limit
thermostats TR, SND, LM.
Check that the room thermostat operates the burner
not the fan.
Check that the motor absorption is not more than
stated on data plate.
Check that the relays (type 4 - 5 - 6- and type 2 - 3
up rated fan) correspond to the value on the data
plate
Check that the flue venter and axial fan are working
correctly.
Check that the fan runs on 3–4 minutes after the
burner has shut down.
Check output corresponds to that on the data plate.
Check that the air flow corresponds to that shown in
the data plate and the duct calculations are correct.
Check that the temperature rise across the heater is
as per the data plate
Check that there is no condensate in the flue
gasses.
MAINTENANCE
It is a requirement that only qualified personnel are
allowed to carry out installation commissioning or
servicing.
Before commencing any maintenance or servicing work
the heater must be shut down and allowed to cool, and
have the gas and electric supplies to it turned off at the
supply cock and isolator respectively.
In order to carry out analyses of the Flue gasses sample points must be made at the following dimensions See Diagram
1
200
1
200
2
2
1. Combustion by-product sampling point
2. Combustion air sampling point
•CLEANING OF EXHAUST AND INTAKE DUCTS
The cleaning of the exhaust and combustion air intake ducts consists of the mechanical removal of dust and any foreign
substances which may have been deposited internally.
•CENTRIFUGAL FAN MAINTENANCE
Cleaning of the fan consists of the mechanical removal
of dust and any foreign substances which may have
been deposited on the fan wheel, motor and intake
grate. Periodically, check the transmission belt tension
and the alignment between motor pulley and the fan
pulley.
The belts must not be tighter than is necessary in
order to prevent sliding; on pressing the two sides of
the belt with hands, the belt must give at least 2-3 cm.
To regulate the transmission use the special belt
tightening system.
CLEANING OF EXHAUST EXTRACTOR
Cleaning of the exhaust extractor consists of the mechanical removal of dust and any foreign substances which may
have been deposited on the fan.
LIMIT THERMOSTAT
Annually, check the LIMIT thermostat is functioning properly, disconnecting the special bridge marked
TEST and checking that the burner stops.
CLEANING OF BURNER
Cleaning of the burner takes place by removing it from its housing and removing any scale which may have been
deposited on the tubing, using exclusively compressor air or brass brush. Any broken tubes or packing must be replaced.
36
CLEANING OF HEAT EXCHANGER
Cleaning of the heat exchanger must be carried out by authorized personnel and is governed by specific regulations. As
a guideline cleaning should take place at least once a year, at the beginning of the winter.
For this operation proceed as follows:
•
•
•
•
•
•
•
•
Remove burner (1) from its housing after having disconnected the gas solenoid valve unit;
Remove upper panel (2);
Remove inspection door (3);
Remove conveyor (4);
Brush the exchange elements (5);
Remove any soot which may have fallen from the exchange elements into the combustion chamber (5);
Clean all the external surfaces of the heat exchanger;
Reassemble everything, paying particular attention to tightness and substituting packing if necessary.
37
FAULT FINDING
If heater is not working firstly check the following:
•
•
•
Check electrical supply
Check gas pressure
Check gas pressure is a stated in Technical Data
FAULT
CAUSE
SOLUTION
No operation
No electrical supply
Check main isolator.
Check supply cables.
Check line fuses.
Check electrical connections
No spark ignition.
Flue venter working
No indication lights on
Differential pressure switch not
working
Check flue pipe and combustion
air pipe are clear
Replace differential pressure
switch
Check air pipes
Check electrical connection
Check that the air pipes are
condensate free
Change flue venter
Change control box
Faulty ionization electrode
Check the electrode is not
cracked or damaged
Check the probe
Room thermostat open
Check room thermostat
Change flue venter
Faulty control box
Change control box
Phase and Neutral inverted
Check
supply
Check electrical connection to
the probe.
Check probe
Change ionization probe.
Check that the gas type is
suitable for heater
Check gas pressure
Check head pressure.
Check gas supply pipes have
been purged of air.
Faulty differential pressure
switch
Poor connection at pressure
switch
Faulty flue venter
Faulty control box
No ignition
Flue venter not working
No indication lights on
Faulty flue venter
Burner lights but cuts out
after 5 seconds
polarity
of
electrical
Faulty ionization probe
Faulty ignition
38
Explosive start up
Faulty ignition electrode
Change ignition electrode
Reposition electrode correctly
over the burner bar
Change burner tube
Change transformer
Check that the gas type is
suitable for heater
Check gas pressure
Check head pressure.
Check gas supply pipes have
been purged of air.
Check heat exchanger
Check air intake pipes are not
blocked .
Check flue pipes are not
blocked check operation of flue
venter
Replace differential pressure
switch
Check position of thermostat
Check that the gas type is
suitable for heater
Check gas pressure
Check head pressure.
Check injector size is correct for
the heater
Check that the fan blades are
clean.
Check that the horizontal and
(vertical if fitted) louvres are
sufficiently
open
(see
installation).
Check fan is operating correctly
with sufficient air flow.
Change SND thermostat or fan
control l
Check that the gas type is
suitable for heater
Check gas pressure
Check head pressure.
Check injector size is correct for
the heater
Incorrect electrode position
Faulty burner tube
Faulty ignition transformer
Faulty ignition
Heat exchanger dirty
Burner shuts down
No indication lights on
Pressure differential switch not
operating
Faulty differential pressure
switch
Room thermostat in hot air flow
The burner goes out due to
the
intervention
of
the
thermostat SND; and is
restarted automatically when
heater has cooled down
Yellow light on.
Excessive
heat
temperature
exchanger
Excessive air temperature due
to poor air flow.
Faulty SND thermostat or faulty
fan control l
The burner goes out due to
the
intervention
of
the
thermostat
TR.
and
is
restarted automatically when
heater has cooled down
Yellow light on.
Excessive
heat
temperature
39
exchanger
Check that the fan blades are
clean.
Check that the horizontal and
(vertical if fitted) louvres are
sufficiently
open
(see
installation).
Check fan is operating correctly
with sufficient air flow
Faulty thermostat
Change thermostat
Excessive air temperature due
to poor air flow.
Control box will not reset.
Red light illuminated
Faulty flame control module
Change control module check
electrical connections
Fan works intermittently
Faulty FAN operation
Change fan control or SND
thermostat
Check that the gas type is
suitable for heater
Insufficient gas pressure
Check gas pressure
Check head pressure.
Check injector size is correct for
the heater
The fan does not work
Faulty FAN operation
Change fan control or SND
thermostat
Faulty fan
Check fan operation
Check fan motor.
Re check heat output required
for application
Check that the gas type is
suitable for heater
Heater works continuously
without reaching the required
temperature
Heater to small for application
Insufficient gas pressure
Check gas pressure
Check head pressure.
Check injector size is correct for
the heater
Dirty heat exchanger
40
Clean heat exchanger
BENSON HEATING LUDLOW ROAD KNIGHTON POWYS LD7 ILP
Tel 01547 528534
Fax 01547 520399
www.bensonheating.com
Benson Heating is a Division of Benson Climate Systems Ltd
15/09/03 Rev. 1
Cod. 016-MN
41