Roberts Gorden Dualair DA260G Series Operating instructions

FOR YOUR SAFETY
If you smell gas:
1. Open windows.
2. DO NOT try to light any appliance.
. DO NOT use electrical switches.
4. DO NOT use any telephone in
your building.
5. Leave the building.
6. Immediately call your local gas
supplier after leaving the building.
Follow the gas suppliers
instructions.
Do not store or use petrol or other
flammable vapours and liquids in the
vicinity of this or any other appli-
ance.
Failure to follow these instructions
can result in death, injury or property
damage.
WARNING
Improper installation, adjustment, alteration,
service or maintenance can result in death, injury
or property damage. Read the Installation,
operation and service manuals thoroughly before
installing or servicing this equipment
Installation must be done by a contractor qualified
in the installation and service of gas/oil fired
heating equipment (whichever is applicable).
Installer
Please take time to read and understand these
instructions prior to any installation. Installer must
give a copy of this manual to the user/owner.
Owner/User
Keep this manual in a safe place close to the heater
to provide your serviceman with information should it
become necessary.
Roberts-Gordon Europe Ltd.
Oxford Street
Bilston, West Midlands WV14 7EG UK
Telephone: [phone]
Fax: [phone]
email: [email protected]
www.combat.co.uk
www.rg-inc.com
V1
Heating & Cooling Unit
DA260G AND VARIANTS
DA300G AND VARIANTS
DA300L AND VARIANTS
DA325G AND VARIANTS
DA380G AND VARIANTS
DA380L AND VARIANTS
Installation, Commissioning,
Service & User Instructions
WARNING
Fire Hazard
X525 02/03
© Copyright 2002 Roberts-Gordon

Details of condense drain for cooling coil

Page1
The gas heater section of these appliances have been tested and certified as
complying with the essential requirements of the Gas Appliance Directive,
The Low Voltage Directive and The Electromagnetic Compatibility Directive
for use on natural gas and L..P.G. gas when installed, commissioned and
maintained in accordance with these instructions . The complete appliances
comply with the requirements of the Machinery Directive .
These instructions refer to appliances designed to operate in the following
countries:
Ireland (IE), Spain (ES), Italy (IT) & United Kingdom (GB ).
Appliances designed for other countries are available on request.
This Appliance must be installed in accordance with the rules in force and
used only in a sufficiently ventilated space, as specified in these instructions.
Before installation, check that the local distribution conditions, nature of gas
and pressure, and adjustment of the appliance are compatible.
IMPORTANT NOTE
ForheatersfittedwithModulatingor High/Lowburners,theseinstructions shouldberead inconjunction
with the relevant sections of the Supplement Manual supplied with the heater.

Page2
Contents
The parts of this manual are numbered by section, clause and sub-clause. Hence 1:2:3 refers to
Section 1, clause 2, sub clause 3. Figure numbers also follow this notation, hence Fig. 2:3 is Section
2, Fig. 3.
SECTION
1. General Specification
2. Technical Data
3. Heater Installation
4. Commissioning of the Air Heater
5. Wiring Diagram
6. Servicing Instructions
7. Removal and Replacement of Parts
8. Fault Finding Charts
9. User Instructions
10. Conversion between natural gas and L.P.G - On/Off burners only
11. Parts List
12. Commissioning Data Sheet
THE AIR HEATER SECTIONS OF THE ON/OFF BURNER APPLIANCES ARE FOR USE WITH
NATURAL GAS OR L.P.G ONLY AS STATED ON THE HEATER DATA PLATE (Conversionbetween
gasses must be carried out in accordance with section 10 of these instructions)
THESE INSTRUCTIONS ARE TO BE LEFT WITH THE USER OR NEAR THE HEATER
Note:Everyeffortismade toensurethatthe informationcontainedinthis Manualisaccurate. However,
Roberts-Gordon reserves the right to alter specifications without prior notice.
Roberts-Gordon shall not be liable to rectify any defects or damage caused by any modifications
madeor attemptedtobemade totheheating unitsbythe customer, hisservants,agentsor employees.

Page3
Section 1. General Specification - DualAir® Unit
1.1 Basic Information
1.1.2 Description
The DualAir® combined heating and cooling unit is formed by four sections combined into a single
unitand deliveredas acomplete assemblyreadyfor installationon site.The DualAir®unit isdesigned
to be installed with the air flow from right to left as shown in Fig 1.1. Units with opposite air flow
direction are available by special order.
The four sections are as follows:-
1.1.3 Gas Fired Heater Section
The heater section is a CUHD/A 300 or the CUHD/A 380 automatic ignition unit heater and contains
the burner controls, the electrical terminal box for the system, the control relays for the operation of
the heater/cooling equipment, and the transition piece between the heater and the fan compartment.
The heater is an open flued gas fired heater of flue type B11 for vertical flue.
The On/Off heaters are Cat II 2H3+ appliances for use with Natural Gas or L.P.G. as stated on the
heater data plate (Modulating and High/Low burners are Cat I2H for use with Natural Gas only), and
are intended for indoor installation only. They must be installed and commissioned in accordance
with local regulations and the requirements of Section 3 of these Instructions.
Apermanent electricalsupply of400 volts50 Hz,threephase andNeutral isrequired forthe operation
of the heater and fan and all models must be earthed. (Note the burner operates on 230v 50 Hz taken
internally from the above supply).
1.1.4 Fan Section
The fan section houses the double-inlet, belt-drive centrifugal blower fan and three phase electric
motor. This section of the cabinet is fully insulated with foil faced glass fibre insulation.
The fan rotation is counter clockwise viewed from the control side as marked on the fan case.
1.1.5 Cooling Coil
DualAir® units can be fitted with either a DX or Chilled Water cooling coil:
1.1.5.1 DX Coil
The DX cooling coil is installed into the DualAir® unit with the two refrigerant circuits sealed ready for
site connection. There are no other refrigerant controls supplied with the coil and all refrigerant pipe-
work and controls must be supplied by the installer to suit the equipment being installed with the
condenser units.
DXcoils aredesignedfor operationat anambienttemperature of28°Cusing R22orR407C refrigerant
evaporating at 6°C.
Theinstallation ofthecooling condensersandtherefrigerantcircuitsmustbe carriedoutin accordance
with the condenser manufacturers instructions.

Page4
1.1.5.2 Chilled Water Coil
A single chilled water coil can be fitted as an option. This type of coil is designed to operate at 6°C
'Water On' temperature. There is no other equipment supplied with the coil and all chilled water pipe-
work and controls must be supplied by the installer to suit the equipment being installed with the
Chiller units.
The installation of the Chiller units and the refrigerant circuits must be carried out in accordance with
the condenser manufacturers instructions.
1.1.6 Filters
Thestandard filterssuppliedwith theDualAir®unit areFarr3030 gradeEU4.These filtersarerequired
to protect the cooling coil from airborne particles.
Filters must be fitted and maintained to ensure proper operation of the equipment.
1.1.7 Controls
See Section 3.9
1.2 Heater Operation
1.2.1 Automatic Ignition Burner
Roberts-Gordon CUHD/A range warm air heaters are fitted with an automatic ignition control which
ignites the gas and monitors for the safe operation of the burner each time the external controls call
for the heater to operate.
1.2.2 Operation - Heater Section
When the external controls call for heat, the burner operates to supply heat to the heat exchanger.
The air delivery fan will also start to run turned on by the fan relay, supplying warm air to the building.
When the external controls are satisfied they will turn off the burner leaving the fan running to cool
down the heat exchanger. When cool enough the fan thermostat will turn off the fan.

Page5
Fig 1.1 General Arrangement
Air Flow
MainHeaterSection
Flue
AirOutletSpigot
BurnerControls MainFan Unit CondenseDrain
Cooling Coil
FilterPanels
AirInletSpigot
Connectionsfor
refigerantpipework
FilterPanels
access
ElectricalTerminal
boxforall connections

Page6
Fig. 2.1 DualAir® 300 Module - Dimensions
Section 2. Technical Data
FRONT VIEW REAR VIEW
SIDE VIEW

Page7
Fig. 2.2 DualAir® 380 Module - Dimensions
FRONT VIEW REAR VIEW
SIDE VIEW

Page8
Fig. 2.3 Design Graph - DualAir® 300 - DX COIL
Fig. 2.4 Design Graph - DualAir® 380 - DX COIL
Graph of Air Flow v Static Pressure for
Model DualAir 300 Range with 4.0kW Motor
0
20
40
60
80
100
120
140
160
180
200
2.5 2.6 2.7 2.8 2.9 3.0 3.1 3.2 3.3
Air Flow m3/sec
Static Pressure Pa
Air flow with 118 mm motor pulley
Graphof Air Flow vStatic Pressure
for ModelDualAir®380 (DX Coil) with 4.0kw Motor
0
50
100
150
200
250
300
350
2.6 2.8 3 3.2 3.4 3.6 3.8 4 4.2
Air Flow m³/sec
Static Pressure Pa
Air Flow 125 mm Pulley

Page9
Fig. 2.5 Design Graph - DualAir®300 - CHILLED WATER COIL
Fig. 2.6 Design Graph - DualAir®380 - CHILLED WATER COIL
Graph of Air Flow v Static Pressure
for DualAir®Model 380 with Chilled Water Coil
4kW motor with 125mm PCD pulley. Fan Pulley 180mm
0
50
100
150
200
250
300
350
2 2.2 2.4 2.6 2.8 3 3.2 3.4 3.6 3.8 4
Air Flow m3/s ( Minimum air flow 2.6 m3/s )
Static Pressure Pa
Air Flow v Externalstatic pressure
Graph of Air Flow v Static Pressure
for DualAir®300 with Chilled Water Coil
4kW motor with 118mm pcd pulley. Fan pulley 180mm pcd
0
40
80
120
160
200
2 2.2 2.4 2.6 2.8 3 3.2
Air Flow m3/s (Minimum air flow 1.9m³/s)
Static Pressure Pa
Static Pressure Pa

Page10
Table 2.5 General Technical Data
# The pressure loss across dirty filters should not be allowed to exceed 150 Pa (1.5 mbar)
ataDlacinhceTriAlauD
003®riAlauDledoM083®riAlauDledoM
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wolFriAdengiseD wolFriAelbatpeccA.niM wolFriAelbatpeccA.xaM m88.2
3
#sretlifnaelchtiwces/ ces/³m66.1 ces/³m17.3 m7.3
3
#sretlifnaelchtiwces/ ces/³m6.2 ces/³m43.5
tinUnaF yelluPnaF yelluProtoM stlebeeV evirdtlebtelnielbuod684-754 DCPmm081A2 DCPmm811A2 46Affo2 evirdtlebelbuod0051x0051 DCPmm081A2 DCPmm521A2 95Affo2
sliateDlacirtcelE
rotoMesahPeerhTzH05v004.Wk4 A7.8tnerrucdaollluf A03tnerructratS esahPeerhTzH05v004.Wk4 A7.8tnerrucdaollluf A03tnerructratS
tinu®riAlauDotylppuslacirtcelElartuen&esahpeerhtzH05v004lartuen&esahpeerhtzH05v004
daollacirtcelelatoTWk1.6Wk1.6
retaehmorfdeilppusstiucriclortnoCA5desufzH05v032A5desufzH05v032
XD-lioCgnilooC
daolgniloocmumixaM snoitcennoctiucricgnilooC noitcennocniardesnednoC .stiucricowtotnitilpsWk8.45 reppocDmm82xDmm22 "4/3cR .stiucricowtotnitilpsWk27 reppocDmm53xDmm22 "4/3cR
noitceSretliF
dettifsretliF4UEedarg0303rraF 89x144x495ffo4 4UEedarg0303rraF 89x144x495ffo4 89x144x982ffo2
ataDlacisyhP
gkthgieW056007
m1tatenibacmorfgnitaResioN m1tatelniriamorfgnitaResioN )a(Bd16RN )a(Bd56RN )a(Bd16RN )a(Bd56RN
Notes:
Fan Pulley, Motor Pulley and Vee Belt sizes are dependant upon the specified air flow/static pressure
requirements. Refer to loose insert sheet for data and performance curves, if applicable.

Page11
Table 2.6 Gas Heater Section - Technical Data (On/off Burner)
003riAlauD083riAlauD
Wk-vcssorGtupnItaeH 011041
rh/utB-vcssorGtupnItaeH 023573086774
Wk-vcteNtupnItaeH 1.991.621
rh/utB-vcteNtupnItaeH 361833093034
Wk-tuptuOtaeH.xorppA 09.6806.011
rh/utB-tuptuOtaeH.xorppA 305692763773
srenruBforebmuN 5191
noitcennoCsaG "¾R"1R
SAGLARUTAN
ezisrotcejnI 49.x749.x7
kramdna 048048
rabm-erusserPrenruB 5.014.11
GWsni-erusserPrenruB 2.465.4
rh/³M-etaRsaG 84.0143.31
rh/³tf-etaRsaG 2.0731.174
EPYTEVLAVSAG T.I.SllewyenoH
avoN2001BA024RV
711-228-0
oNTRAP 124LB950L
SAGGPL
eziSrotcejnI mm45.0x7mm45.0x7
kramdna 052052
ENAPORP
rabm-erusserPtelnI 7373
GWsnI-erusserPtelnI 8.418.41
rh/³M-etaRenaporP 41.472.5
rh/gk-etaRenaporP 68.710.01
rh/rtLdiuqiL-etaRenaporP 4.516.91
ENATUB
rabm-erusserPtelnI 9292
GWsnI-erusserPtelnI 6.116.11
rh/³M-etaRenatuB 51.310.4
rh/gk-etaRenatuB 00.891.01
rh/rtLdiuqiL-etaRenatuB 59.3167.71
EPYTEVLAVSAG avoN.T.I.SllewyenoH
711-228-02001BA024RV
)rotalugeRoN()rotalugeRoN(
oNTRAP 124LB950L
Data shown is for On/Off burner. For Modulating and High/Low burners, please refer to data for
CUH/A300 and CUH/A380 units in the relevant Manual Supplement supplied.
Gas supply pressure required.(with burner running)
Natural Gas [G20] inlet pressure 20 mbar (17-25)
Propane gas [G31] inlet pressure 37 mbar (25-45)
Butane gas [G30] inlet pressure 29 mbar (20-45)

Page12
2.1 Gas Controls - Automatic Ignition (On/Off Burner*)
The heaters may be fitted with one of two types of gas control valves dependent upon the model,
each giving the same control elements as follows (see Section 4)
2.1.1 Main Gas Burner
The multifunctional main gas valve contains a gas regulator and two automatic shut off valves. When
set up as defined in Section 4 the valves will have a step opening operation on the main gas to give
smooth lighting. Settings of the valves are given in Section 4 and tables in Section 2.
2.1.2 Start Gas Burner
There is one solenoid valve to control the pilot burner gas supply which is designed to operate at inlet
pressure and therefore does not need a regulator.
* Note: For Modulating and High/Low burners, please refer to the Manual Supplement supplied.
2.2 Main Fan
The main air moving fan fitted to these appliances is operated automatically by the fan thermostat
within the Honeywell combination fan/limit thermostat and the Fan relay when in the heating mode or
the relevant relay for the current external demand when in the cooling mode.
2.3 Limit Thermostats
There are two limit thermostats on these heaters to protect them from overheating, should the air flow
fail for any reason. One is within the Honeywell combination thermostat and the second is situated on
the side of the heater towards the rear of the CUHD heater section.
2.3.1 Honeywell Combination Fan/Limit Thermostat
The combination fan/limit thermostat is a dual function control and safety device (see Fig. 2.2).
Fan Thermostat
The fan thermostat controls the operation of the main fan during the heater operating cycle. This
control also ensures that the main fan continues to run after the burner turns off to dissipate the
residual heat from the heat exchanger.
The white button on the fan thermostat should be pulled to its “out”position for normal operation. In
the “pushed in”position the fan will run continuously.
Limit Thermostat
The limit thermostat operates in overheat conditions caused by insufficient air passing over the heat
exchanger. This is a manual reset device and is reset by pressing in the red reset button on the
thermostat. Note the heat exchanger must have cooled to below the operating temperature for reset
to be possible.

Page13
Fig. 2.2 Combination Fan/Limit Thermostat
WARNING:IT IS ESSENTIAL THAT THE BREAK OFF LINK SHOWN IS REMOVED
IN THE EVENT OF THERMOSTAT REPLACEMENT
2.3.2 Second Limit Thermostat
This is a manual reset device - see Figs. 1 .1 & 2.1.
Note: On the DualAir®models these are fitted so that the sensing element is on the lower rear of the
heat exchanger in the same way as for the standard CUHD unit heater. The operating head of the
thermostat is located on the side panel of the CUHD heater section.
To reset this thermostat:
a) Remove the screw on cover of the thermostat .
b) Push in the button in the centre of the thermostat. Note: the heat exchanger must be cooled to
allow this to happen.
c) Replace the cover.

Page14
2.4 Fan Relay (R1 on wiring Diagram)
This two pole relay is provided to ensure that the fan will always run when the burner is firing,
as the temperature rise through the heat exchanger is much lower than for the standard heater, due
to the increased air flow. This Relay is additional to the fan thermostat which still provides for the "fan
run on" after burner operation.
2.5 Automatic Ignition - Burner Control Box
2.5.1 Description of Satronic DKG 972 Control Box
The fully automatic gas burner fitted to all CUHD/A models is controlled by a Satronic TFI 812 2B
Mod 10 plug-in control box. This control ensures the safe start and stop sequence and also monitors
the safe presence of a flame.
Fig 2.3 Satronic DKG 972 Control Box Sequence
2.5.2 Sequence of Events
With the external controls on and calling for heat, the control box will self check and then begin a start
sequence.
Electric Ignition ON
Start Gas Valve Energises
The start gas valve opens and once a flame has been established this remains on until close down.
The flame probe is now continuously monitoring for the safe presence of flame.

Page15
Fig. 2.4 Motor Starter and Thermal Overload
Electric Ignition OFF
Five seconds later the electric ignition turns off, leaving the start gas flame to be proved as stable.
Main Gas Valve Energises
Following a short delay the main gas valves energise and the main flame cross lights from the start
gas. The control is now in its normal run position.
Close Down
When the external controls are satisfied the control box turns off all outputs simultaneously and
returns to rest position for the beginning of the next sequence.
2.5.3 Fault Conditions
If at any stage the flame fails the control will go to ‘lockout'. The red light will glow and the control will
need to be manually reset before any further start attempt can be made.
Minimum flame probe current 1 µA DC.
Typical flame probe current 3-5 µA DC (on main flame)
2.6 External Controls
DualAir®range heaters may be operated from external controls as described in sections 4 & 5.
The wiring diagrams for the external controls are shown in Section 5.

Page16
2.7 Motor Starter and Thermal Overload
On belt driven fan models the motor is controlled by a direct on line contactor starter fitted with
thermal overload protection. If the thermal overload should operate the main fan will not run. To reset,
press in the reset button on the overload unit (see Fig. 2.4).
The overload should be set to indicate approximately 0.2 amps above the normal running current of
the heater.
Note: Running the fan with the fan compartment access panels removed may cause the thermal
overloads to operate due to the reduced resistance on the fan.
2.8 Frost Thermostat for the Cooling Coil
As part of the built in equipment a frost protection thermostat is fitted to protect the cooling coil from
freezing should the air flow fall to a low level during the cooling cycle.
It is strongly recommended that this control is connected and set (see 4.10) to give the cooling
coil protection from freezing which would cause severe damage.
2.9 Pressure Switch for the Cooling Coil/Filters
As part of the built in equipment a differential pressure switch is fitted to monitor the overall pressure
loss across the cooling coil and filters. The control is designed to turn off the control circuit of the
external condenser units to prevent any damage to the cooling coil due to blocked filters or other
reduced air flow. This should be set on site to reflect the installed conditions and to monitor the
differential pressure across the coil and filter.
The pressure setting on this pressure switch should be set so that the filter pressure switch (2.10)
operates first to give warning of impending problems
2.10 Pressure Switch for Air Filters
As part of the built in equipment a differential pressure switch is fitted to monitor the pressure loss
across the filter section.
The control is designed to turn on the built in amber warning light and also provide a 230v output at
terminals 22 & 23 for remote indication of the filters becoming blocked. This is an indication only and
warns that the filters need attention and should be set on site to reflect the installed conditions and to
monitor the differential pressure across the filter.
The maximum recommended final resistance across a dirty filter is 150 Pa (1.5 mbar).

Page17
Section 3. Heater Installation
3.1 Required Standards
It is important that all gas appliances are installed by competent persons, in accordance with the
relevant requirements of the local laws and regulations. Failure to install gas appliances correctly
could lead to prosecution.
THE RELEVANT REGULATIONS ARE:
Gas Safety (Installations and Use) Regulations 1994;
BS 6230 Specification for the Installation of Gas Fired Forced Convection Air Heaters for Commercial
and Industrial Space Heating of Rated input Exceeding 60kW;
BS 6891 Installation of Low Pressure Pipes up to 28mm (R1) or
Institute of Gas Engineers Documents IGE/UP/1 and IGE/UP/2 as appropriate;
BS 5588 Part 11 Fire Precautions In the Design and Construction of Buildings;
Building Regulations; The I.E.E Regulations; The Health and Safety at Work etc. Acts; Any
Requirements of the Local Authority, Fire Officer and Insurance Company.
The installation will be similar to the one shown in Figure 3.1.
WARNING:
AIR HEATERS SHOULD NOT BE INSTALLED IN CORROSIVE ATMOSPHERES
i.e. NEAR PLATING OR DEGREASING PLANTS OR IN AREAS WHERE THERE IS A FIRE
RISK.
CONSULT LOCAL REGULATIONS FOR FURTHER INFORMATION ON HAZARDOUS AREAS.
The cooling equipment should be installed in accordance with the manufacturer's instructions and
any local installation rules.
3.2 General Installation information
3.2.1 Handling
The Dual-Air unit is provided with 6 eye bolts positioned at the four corners and the centre of the unit.
The unit may be lifted from these points using a support cradle to prevent side load from damaging
the panels.
The lifting points that form part of the CUHD unit heater are not capable of supporting the
weight of the complete unit.

Page18
3.2.2 Installation
For installation the unit may be supported by the 6 lifting eyes provided, from positions vertically
above each point. Alternatively the 12mm D screwed rod which is supplied connecting the eye bolts
to the base frame may be replaced with extended 12mm rod or similar to provide a continuous
support system. In all cases it must ensured that the support system is adequate to support the full
weight of the unit (see Section 2 for details).
The DualAir®combined unit is designed for installation inside the building to be heated/cooled.
If the unit is sited in a plant room then the distribution air must be ducted to and from the unit and
adequate provision must be made for the combustion air as described in Sections 3.5 & 3.6.
When sited above floor level then a suitable access platform should be provided to provide safe
working conditions for the routine maintenance of the burner, fan and filters.
Access for burner maintenance is required at the heater front (under the outlet spigot) and to the
controls compartment (see Fig 1.1).
Note that for burner withdrawal a clear area of at least 1.1m is required directly in front of unit.
It is important to ensure that at all times there is adequate air circulation around the heater to supply
air for combustion, ventilation and distribution.
Consideration should also be given when siting a heater to allow for the proper location of the flue.