Roberts Gorden CUHA, CUHC, CUHD, CUHA/A, CUHB/A Installation, Commissioning, Operation & Service Manual

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Page 1

FOR YOUR SAFETY

If you smell gas:

1. Open windows.

2. DO NOT try to light any appliance.

3. 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.

7. If you cannot reach your gas supplier, call the Fire Department.

C mbat

Unit Heaters

Installation, Commissioning,

WARNING

Fire Hazard

Do not store or use petrol or other flammable vapours and liquids in the vicinity of this or any other appliance.

Failure to follow these instructions can result in death, injury or property damage.

Operation & Service Manual

Model CUH

(A, B, C, D)

60 to 240 Manual Ignition

Model CUH

(A/A, B/A, C/A, D/A)

60 to 380 Automatic Ignition

WARNING

Improper installation, adjustment, alteration, service or maintenance can result in death, injury or property damage. Read the installation, operation and service manual thoroughly before installing or servicing this equipment.

Installation must be done by a registered installer/ contractor qualified in the installation and service of gas-fired heating equipment or your gas supplier.

Quality in Any Language™

Installer

Please take the time to read and understand

these instructions prior to any installation.

Installer must give a copy of this manual to the owner.

Owner

Keep this manual in a safe place to provide your

serviceman with information should it become

necessary.

Roberts-Gordon

Oxford Street

Bilston, West Midlands WV14 7EG UK

Telephone: +44(0) 1902 494425 Fax: +44(0) 1902 403200 Service Telephone: +44(0) 1902 498733 Service Fax: +44(0) 1902 401464 Export Sales Telephone: +44(0) 1794 521562 Export Sales Fax: +44(0) 1794 521387 E-mail: uksales@rg-inc.com E-mail: export@rg-inc.com

www.combat.co.uk www.rg-inc.com

X404E Rev A 07/02

Page 2

Page 3

TABLE OF CONTENTS

...................................................................Product Approval 1

SECTION 1: Heater Safety......................................................2

SECTION 2: Installer Responsibility .....................................2

2.1 Low Level User Instructions......................................... 2

2.2 Corrosive Chemicals....................................................2

2.3 National Standards and Applicable Codes ..................2

SECTION 3: Critical Considerations .....................................3

3.1 Basic Information.........................................................3

3.2 Location and Suspension ............................................3

3.3 Minimum Required Clearances to Combustibles.........3

3.4 Ventilation .................................................................... 3

3.5 Gas Supply ..................................................................3

3.6 Electrical Supply..........................................................3

3.7 Flue..............................................................................3

SECTION 4: Specifications .................................................... 6

4.1 All Models....................................................................6

4.2 Components Identification...........................................7

4.3 General Technical Data Table (all models) ..................8

4.4 Technical Data Table - CUHA, CUHB, CUHC and

CUHD Manual Ignition Range.....................................9

4.5 Technical Data Table - CUHA/A, CUHB/A, CUHC/A

and CUHD/A Automatic Ignition Range .................... 10

4.6 Gas Controls - Automatic Ignition .............................. 11

4.7 Gas Controls - Manual Ignition .................................. 11

4.8 Main Fan.................................................................... 11

4.9 Limit Thermostats ......................................................11

4.10 Thermocouple Interrupter Relay .............................. 11

4.11 Automatic Ignition - Burner Control Box ..................11

SECTION 5: Heater Installation............................................ 13

5.1 General......................................................................13

5.2 Handling .................................................................... 13

5.3 Shelf Mounting and Suspension ................................13

SECTION 6: Flue Installation ............................................... 14

6.1 Flue Installation ......................................................... 14

6.2 Models 340 and 380 only ..........................................16

SECTION 7: Air Supply ......................................................... 17

7.1 Air Supply .................................................................. 17

7.2 Building Ventilation .................................................... 17

SECTION 8: Optional Heater Configurations .....................18

8.1 Distribution Ductwork for CUHB, CUHC and CUHD

Heaters ...................................................................... 18

SECTION 9: Gas Piping ........................................................ 20

SECTION 10: Wiring and Electrical Information ................ 21

10.1 Electrical Supply ...................................................... 21

10.2 Remote Controls...................................................... 21

10.3 CUH Individual Controls (all models).......................22

10.4 CUHD External Motor Alternative Wiring

(all models) ..............................................................22

10.5 CUHA Wiring Diagram.............................................23

10.6 CUHB & CUHC Wiring Diagram (60-160) ...............23

10.7 CUHB & CUHC Wiring Diagram (180-240) .............24

10.8 CUHD Wiring Diagram (all models).........................25

10.9 CUHA/A Wiring Diagram (60-240) Satronic.............26

10.10 CUHA/A Wiring Diagram (280-300) Satronic.........27

10.11 CUHA/A Wiring Diagram (340-380) Satronic.........27

10.12 CUHB/A & CUHC/A Wiring Diagram (60-160)

Satronic .................................................................28

10.13 CUHB/A & CUHC/A Wiring Diagram (180-300)

Satronic .................................................................29

10.14 CUHB/A & CUHC/A Wiring Diagram (340-380)

Satronic .................................................................30

10.15 CUHD/A Wiring Diagram (60-300) Satronic...........31

10.16 CUHD/A Wiring Diagram (340-380) Satronic.........31

10.17 CUHA/A Wiring Diagram (60-240) Honeywell........32

10.18 CUHA/A Wiring Diagrams (280-300) Honeywell....33

10.19 CUHA/A Wiring Diagram (340-380) Honeywell......33

10.20 CUHB/A & CUHC/A Wiring Diagram (60-160)

Honeywell ..............................................................34

10.21 CUHB/A & CUHC/A Wiring Diagram (180-300)

Honeywell ..............................................................35

10.22 CUHB/A & CUHC/A Wiring Diagram (340-380)

Honeywell .............................................................36

10.23 CUHD/A Wiring Diagram (60-300) Honeywell .......37

10.24 CUHD/A Wiring Diagram (340-380) Honeywell .....37

SECTION 11: Commissioning The Heater ..........................38

11.1 Pre Commission Checks..........................................38

11.2 Gas Supply ..............................................................38

11.3 Mechanical Checks..................................................38

11.4 Automatic Ignition Unit Heaters ...............................39

11.5 Manual Ignition Unit Heaters....................................42

11.6 Commissioning Tests - (all models)

Spillage Test.............................................................43

11.7 Combustion Testing - (all models)............................43

11.8 Pilot Drop-Out Test - Manual Ignition Models ..........43

11.9 Turning Off the Heater - (all models)........................43

11.10 External Controls ...................................................43

11.11 Complete the Installation .......................................43

11.12 Instruction to the User............................................43

SECTION 12: User Instructions ...........................................44

12.1 User Instructions......................................................44

12.2 Heater Operation .....................................................44

12.3 Common User Controls (all models)........................44

12.4 Automatic Ignition User Controls .............................45

12.5 Automatic Ignition Lighting Instructions ...................45

12.6 Manual Ignition User Controls..................................45

12.7 Manual Ignition Lighting Instructions........................45

12.8 Simple Fault Finding (all models).............................46

12.9 Service Requirements .............................................47

SECTION 13: Servicing.........................................................48

13.1 Servicing Instructions...............................................48

13.2 Fan/Motor Assembly Maintenance

(all models)...............................................................48

13.3 Heat Exchanger Maintenance..................................48

13.4 Gas Control Valve Maintenance (all models)...........49

13.5 Manual Ignition.........................................................49

SECTION 14: Conversion Between Gases..........................50

14.1 General ....................................................................50

14.2 Burner Conversion ...................................................50

14.3 Gas Valves - Automatic Ignition ...............................50

14.4 Conversion of Manual Ignition Valves ......................52

SECTION 15: Troubleshooting.............................................53

15.1 General for Automatic Ignition..................................53

15.2 Troubleshooting For Automatic Ignition Burner

Systems...................................................................55

15.3 Flame Supervision System ......................................57

15.4 Troubleshooting for Solenoid Valves ........................58

15.5 Troubleshooting for Main Fan ...................................58

15.6 Troubleshooting for Fan Contactor...........................59

All rights reserved. No part of this work covered by the copyrights herein may be reproduced or copied in any form or by any means - graphic, electronic, or mechanical, including photocopying, recording, taping or information storage and retrieval systems - without the written permission of Roberts-Gordon.

Printed in U.K.

Page 4

SECTION 16: Removal and Replacement Parts................. 60

16.1 Burner Tray.............................................................. 60

16.2 Main Burner Bars / Injectors.................................... 60

16.3 Pilot Burner Assembly (where fitted). ...................... 62

16.4 Gas Control Valves .................................................. 63

16.5 CUHA Axial Fan/Guard/Motor Assembly................. 63

16.6 CUHB & CUHC Centrifugal Fan/Guard/Motor

Assembly................................................................. 64

16.7 Combination Fan/Limit Thermostat ......................... 64

16.8 Second Limit Thermostat ........................................ 64

16.9 Major Components Descriptions ............................. 66

Page 5

TABLE OF FIGURES

Figure 1: Clearances to Combustibles ......................................4

Figure 2: Flue Termination........................................................5

Figure 3: Offset Flues with 135° bends.....................................5

Figure 4: Ducting ......................................................................5

Figure 5: Combination Fan/Limit Thermostat..........................12

Figure 6: Honeywell Control ................................................... 12

Figure 7: Suspension Methods ...............................................13

Figure 8: Guy Wire ..................................................................14

Figure 9: Socket Direction....................................................... 14

Figure 10: Flue and Roof Detail..............................................15

Figure 11: Flue and Heater Spigot Joint Detail....................... 15

Figure 12: Heaters installed in isolated equipment rooms...... 19

Figure 13: CUH C or D Heaters with Inlet/Outlet Duct

Spigots and Flange................................................19

Figure 14: Gas Connection with Stainless Steel Flex

Connector ..............................................................20

Figure 15: Setting Louvers...................................................... 38

Figure 16: S.I.T. Tandem 0.830.033 Gas Valve

(Natural gas) 0.830.020 Valve (L.P.G) ...................40

Figure 17: S.I.T. Nova 0.822.177 Automatic Ignition

Gas Valve .............................................................. 40

Figure 18: S.I.T. Nova 0.820.054 Manual Ignition

Gas Valve .............................................................. 41

Figure 19: Main Gas Valves for Models 340 and 380 .............41

Figure 20: Heater Operating Sequence ..................................44

Figure 21: Fan/Limit Thermostat ............................................. 44

Figure 22: S.I.T. Nova Valve for Manual Ignition,

Operation............................................................... 46

Figure 23: Pilot Burner Options .............................................. 50

Figure 24: Conversion of Nova Family Valve ..........................51

Figure 25: Conversion of Honeywell Gas Valve for L.P.G. ......51

Figure 26: Automatic Burner Control Box Sequence ..............56

Page 6

Page 7

Product Approval

ROBERTS GORDON® appliances have been tested and certified as complying with the essential requirements of the Gas Appliance Directive, The Low Voltage Directive, The Electromagnetic Compatibility Directive and the Machinery Directive for use on natural gas and L.P.G. gas when installed, commissioned and maintained in accordance with these instructions.

These instructions refer to appliances designed to operate in the following countries: Austria (AT), Czech Republic (CZ), Denmark (DK), Estonia (EE), Finland (FI), Greece (GR), Ireland (IE), Italy (IT), Portugal (PT), Slovak Republic (SK), Spain (ES), Sweden (SE), Switzerland (CH) & 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.

Page 8

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

SECTION 1: HEATER SAFETY

Your Safety is Important to Us!

2.2 Corrosive Chemicals

This symbol is used throughout the manual to notify you of possible fire, electrical or burn hazards. Please pay special attention when reading and following the warnings in these sections.

Installation, Service and Annual Inspection of heater must be done by a registered installer/contractor qualified in the installation and service of gas-fired heating equipment.

Do not use heater in an area containing corrosive chemicals.

Corrosive chemicals will damage the burner and heat exchanger parts.

Failure to follow these instructions can result in property damage.

Read this manual carefully before installation, operation, or service of this equipment.

Roberts-Gordon cannot be responsible for ensuring

This heater is designed for heating non-residential indoor spaces. Do not install in residential spaces. These instructions, the layout drawing, local codes and ordinances, and applicable standards that apply to gas piping, electrical wiring, venting, etc., must be thoroughly understood before proceeding with the installation.

that all appropriate safety measures are undertaken prior to installation; this is entirely the responsibility of the installer. It is essential that the contractor, the sub-contractor, or the owner identifies the presence of combustible materials, corrosive chemicals or halogenated hydrocarbons* anywhere in the premises.

CAUTION

SECTION 2: INSTALLER RESPONSIBILITY

• To install the heater, as well as the gas and electrical supplies, in accordance with applicable specifications and codes. Roberts-Gordon recommends the installer contact a local building inspector, Fire Officer or insurance company for guidance.

• To use the information given in the manual together with the cited codes and regulations to perform the installation.

• To install the heater in accordance with the Clearances to Combustibles of this heater.

• To furnish all needed materials not furnished as standard equipment.

• To plan location of supports and flues.

• To provide access to burners for servicing, for burner removal.

• To provide the owner with a copy of this installation, commissioning, operation and service manual.

• To never use heater as support for ladder or other access equipment and never hang or suspend anything from heater.

• To ensure that there is sufficient ventilation in the area to comply with the requirements of all relevant safety and local regulations.

2.1 Low Level User Instructions

In all situations, clearances to combustibles must be maintained. See Page 4, Figure 1.

* Halogenated Hydrocarbons are a family of chemical compounds characterized by the presence of halogen elements (fluorine, chlorine, bromine, etc.). These compounds are frequently used in refrigerants, cleaning agents, solvents, etc. If these compounds enter the air supply of the burner, the lifespan of the heater components will be greatly reduced. Warranty will be invalid if the heater is exposed to halogenated hydrocarbons.

2.3 National Standards and Applicable Codes

All Appliances must be installed in accordance with the latest revision of applicable standards and national codes. This refers also to the electric, gas and venting installation. Note: Additional standards for installations in Public Garages, Aircraft Hangars, etc. may be applicable.

• 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.

• BS 5440 Parts 1 Installation of Flues and Ventilation of Gas appliances of Rated Input Not Exceeding 60kW.

Page 9

SECTION 3: CRITICAL CONSIDERATIONS

3.1 Basic Information

The following types of heaters in the CUH range are covered by these instructions and are for ON/OFF operation only. High/Low or modulating versions are covered in a supplement.

SECTION 3: CRITICAL CONSIDERATIONS

3.4 Ventilation

It is important to ensure that there is adequate air circulation around the heater to supply air for combustion, ventilation and distribution in accordance with local codes.

Fan Type Manual Ignition Automatic Ignition

Axial CUHA 60 to 240 CUHA/A 60 to 380 Centrifugal CUHB 60 to 240 CUHB/A 60 to 380

Ducted Inlet CUHC 60 to 240 CUHC/A 60 to 380

No Fan CUHD 60 to 240 CUHD/A 60 to 380

COMBAT® CUH ranges of unit air heaters are type B11 appliances for vertical flue. Models in the 80 to 380 range are for use with natural gas or L.P.G. as stated on the heater data plate. Models 60 are for use with natural gas only. All models are intended for indoor installation only.

3.2 Location and Suspension

All models must be installed in a level position and may be suspended from above (See Page 13, Figure 7) or from wall brackets of sufficient strength to support the heater as listed in the General Technical Data Table on Page 8, Section 4.3. Drop rods must be a minimum of 10 mm diameter mild steel. Four hanging brackets are located on top of the heater. All heaters may be mounted on a shelf of non combustible material. It is important that the lower front and rear panels remain accessible for burner routine maintenance and repairs. The burner may only be removed from the front lower panel. The rear lower panel must be removed to accomplish this.

3.5 Gas Supply

It is important that the gas supply pipe and the electrical connections do not support any of the heater’s weight.

3.6 Electrical Supply

A permanent 230v 50Hz electrical supply is required at the main electrical terminals. The heater also requires suitable energy controls in accordance with Section 10.

3.7 Flue

Choose heater siting to allow for the proper location of the flue. Each heater must be fitted with an individual and correctly sized stainless steel flue (See Page 6, Section 4). No other appliance may be connected to the flue. It is important that flues are designed to prevent down draughts. It is essential that the spillage test on Page 43, Section 11.6 is carried out.

3.3 Minimum Required Clearances to Combustibles

Clearances around the heater and flue must be as indicated on Page 4, Figure 1 through Page 5, Figure 3 to ensure access for servicing, correct operation and to maintain the clearance to combustibles.

Page 10

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

Figure 1: Clearances to Combustibles

If installed at low levels where individuals can come in contact with hot heat exchanger components, adequate guarding must be provided.

Temperature of any combustible material near the flue must not exceed 65°C when the heater is in operation.

WARNING

Fire Hazard

Some objects will catch fire or explode when placed close to heater.

Keep all flammable objects, liquids and vapors the required clearances to combustibles away from heater.

Failure to follow these instructions can result in death, injury or property damage.

Installation Clearances to Combustibles for all models:

Model A

back of fan

(m)

CUHA

CUHB

CUHC

CUHD

See Figure 4 0.8 2.75 - 3.75 1.1 3.0 0.6

See Figure 4 0.8 N/A 1.1 3.0 0.6

0.6 0.8 2.75 - 3.0 1.1 3.0 0.6

0.6 0.8 2.75 - 3.75 1.1 3.0 0.6

sides

(m)

recommended

mounting height (m)

burner removal

(m)

combustibles

(m)

above

(m)

Page 11

SECTION 3: CRITICAL CONSIDERATIONS

Figure 2: Flue Termination Figure 3: Offset Flues with 135° bends

Flues up to 200 mm dia. are fitted with Bird Screens, over 200 mm with a Rain Cap.

1 m

Minimum

Use adequate support to prevent heater from carrying the weight of the flue.

Figure 4: Ducting

*Less than

2.5 m

Roof

Wall

*1 m

Minimum

*If the point of roof intersection is within 2.5 m of a nearby structure, the flue must terminate at least 1 m above that structure.

Nearby

Structure

1 m

Minimum

above roof

Use adequate support to prevent heater from carrying the weight of the flue.

Minimum Total 1m + (0.5m for each 135° bend) + (1m for each 0.33m of flue running in the 135° direction)

Roof

135°

Wall

All joints between the heater and ductwork should be made as air tight as possible.

Airflow Indicator

Minimum-

Twice

Dimension

X

AIRFLOW

Lower Rear Panel

Minimum-

Twice

Dimension

X

AIRFLOW

Lower Front Panel

Ducting

Dimension

X

Ducting

Area required for

Burner Removal

1.1m

Minimum

Flexible Flange

Dimension

X

Page 12

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

SECTION 4: SPECIFICATIONS

4.1 All Models

Front Views

Side Views

CUHA/B/C Models 60 - 300 CUHA/B/C Models 340 - 380

CUHA Models 60 - 380

CUHB Models 60 - 380

CUHD (and other models fitted with

air outlet spigots) Models 60 - 380

CUHC Models 60 - 380 CUHD Models 60 - 380

Dimension Data - All Models

Model

Ref.

A Width

B Support Spacing

C Flue Diameter

D Inlet & Outlet Spigot Width Weight (CUHA) Weight (CUHB) Weight (CUHC)

Weight (CUHD)

(in)

kg 91 91 110 110 130 130 150 150 190 200 200 210 210

kg 111 111 130 130 150 150 170 180 220 270 270 276 276

kg 128 128 148 148 169 169 191 201 243 295 295 303 304

kg 82 82 92 99 104 114 124 134 154 180 180 190 190

* Duct spigots width for models CUHC and CUHD. Duct spigots ’Height’ shown on above drawings.

Duct spigots are complete with 30 mm mez. flange.

60 80 100 120 140 160 180 200 240 280 300 340 380

519

(20½)

479

(18)

178

(7)

438

(17¼)

519

(20½)

479 (18) 178

(7)

438

(17¼)

589 (23) 549

(21¾)

178

(7)

508 (20)

589 (23) 549

(21¾)

178

(7)

508 (20)

729

(28½)

689

(27¼)

178

(7)

648

(25¼)

729

(28½)

689

(27¼)

178

(7)

648

(25¼)

869 (34) 829

(32¾)

229

(9)

788 (31)

869 (34) 829

(32¾)

229

(9)

788 (31)

1009

(39¾)

969

(38¼)

254

(10)

928

(36½)

1219

(48)

1179

(46½)

254 (10)

1137

(44¾)

1219

(48)

1179

(46½)

254 (10)

1137

(44¾)

1359

(53½)

1319

(52) 305 (12)

1277

(50¼)

1499

(59)

1459

(59) 305 (12)

1417

(55¾)

Page 13

4.2 Components Identification

Terminal Box at lower back of heater on some models.

Bottom of Terminal Box

Green Light-Heater On

Red Light-LockoutReset Button

(Honeywell Control)

SECTION 4: SPECIFICATIONS

Pilot Viewing via cut out

REAR VIEW

FRONT VIEW

Flue Spigot

Gas Connection

Hanging Brackets

Draught Diverter

Honeywell Combination Fan/Limit Stat.

Lighting Instructions

Combustion Air Slots

Data Plate

SIDE VIEW

Electrical Supply via Cable Gland

Electrical Connections for Main Fan, Gas Valve and Interrupter Relay

Reset Button (Satronic Control)

Interrupter Relay (Manual Ignition)

Access to Second Limit Thermostat

Burner Compartment

Air Deflection Grille

Page 14

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

4.3 General Technical Data Table (all models)

MODEL REFEREN CE 60 80 100 120 140 160 180 200 240 280 300 340 380

’A’ RAN GE

Total Electrical Load

Watts

Fan Type

Number of

Fans Fitted

Capacitor µf

Rating - Wa tts

Run C urrent - Amps 0.7 0.7 0.7 0 .86 0.8 6 1.8 1.8 1.5 4 1.54 3.56 3.56 3.5 6 3.56

Start Current - Amps

Air Flow - m³/hr

Air Flow - ft³/min 1583 1583 1942 2248 2380 2770 2580 2684 3737 5480 5480 5519 5519

'B' & 'C' RANGES

Total Electrical Load

Watts

Number of

Fans Fitted

Direct Drive Fan

Motor Details

Size Watts

Normal Set Speed

Normal Run Current

Amps

Normal Start Current

Amps

Maximums at

High Speed

Run C urrent - Amps 6. 1 6.1 6.9 6.9 5. 1 5.1 11.4 11 .4 13 .7 13.7 13 .7 17.9 17.9

Start Cu rrent - Amps

Not to be us ed without

reference to Combat

Air Flow - m³/hr

Air Flow - ft³/min

'D' RANGE

Required

Minimum Air Flow m³/hr

ft³/min

Pressure loss

across heat

exchanger at

required air flow

mbar 0.43 0.43 0.43 0.43 0.43 0.43 0.43 0.43 0.43 0.43 0.43 0.43 0.43

191 191 191 228 228 444 444 384 384 849 849 849 849

Sifan PMG 35041-101

1111111222222

2.52.52.533552 x 2.52 x 2.52 x 52 x 52 x 52 x 5

170 170 170 210 210 180 180 170 170 180 180 180 180

1.9 1.9 1.9 2.3 2.3 3.4 3.4 4.2 4.2 6.7 6.7 6.7 6.7

2690 2690 3300 3820 4044 4706 4383 4560 6350 9310 9310 9376 9376

900 900 1200 1200 1175 1175 1750 2200 2400 2400 2400 3500 3500

1111112222233

TORIN

270-270

1 x 550 1 x 550 1 x 550 1 x 550 1 x 550 1 x 550 2 x 550 2 x 550 2 x 550 2 x 550 2 x 550 3 x 550 3 x 550

LOW LOW MEDIUM MEDIUM MEDIUM MEDIUM LOW MEDIUM MEDIUM MEDIUM MEDIUM MEDIUM MEDIUM

3.9 3.9 5.2 5.2 5.1 5.1 7.5 9.4 10.3 10.3 10 .3 15 15

4.8 4.8 6.4 6.4 6 6 9.3 11.6 12.8 12.772 12.772 18.6 18.6

8 8 8.6 8.6 7 7 13.6 13.6 17.1 17.1 17.1 22.1 22 .1

2500 2600 3100 3200 3250 3260 4480 5700 6200 6700 6800 9400 9400

1471 1530 1825 1883 1913 1919 2637 3355 3649 3943 4002 5533 5533

2500 2600 3100 3200 3250 3260 4383 4560 6200 6800 6800 9376 9376

1471 1530 1825 1883 1913 1919 2580 2684 3649 4002 4002 5519 5519

TORIN

270-270

Sifan PMG 35041-101

TORIN

270-270

Sifan PMG 39041-101

TORIN

270-270

Sifan PMG 39041-101

TORIN

270-270

Sifan PMG

42041-101

TORIN

270-270

Sifan PMG

42041-101

TORIN

241-241

Sifan PMG 35041-101

TORIN

241-241

Sifan PMG 35041-101

TORIN

270-270

Sifan PMG 42041-101

TORIN

270-270

Sifan PMG 42041-101

TORIN

270-270

Sifan PMG 42041-101

TORIN

270-270

Sifan PMG 42041-101

TORIN

270-270

Page 15

SECTION 4: SPECIFICATIONS

4.4 Technical Data Table - CUHA, CUHB, CUHC and CUHD Manual Ignition Range

Appliance Category II

2H3+

Natural Gas Inlet Pressure 20 mbar (17 - 25) Propane Inlet Pressure 37 mbar (25-45) Butane Inlet Pressure 29 mbar (20-35)

MANUAL IGNITION

MODEL NO

Heat Input Gross cv - kW 22.5 29.5 37 43 52 59 66.5 74 89

Hea t Input Gross cv - B tu/hr

Heat Input Net cv - kW 20.3 26.6 33.3 38.7 46.9 53.2 59.9 66.7 80.2

Heat Input Ne t cv - Btu/hr 69170 90689 113746 132191 159859 181379 204435 227492 273605

Approx. Heat Output - kW

Approx Heat Output - Btu/hr 60648 79517 99733 115906 140165 159033 179249 199466 239898

Number of Burners 44567891012

NATURAL GAS

Injector size 7 x .94 7 x .94 7 x .94 7 x .94 7 x .94 7 x .94 7 x .94 7 x .94 7 x .94

Injec tor ma rking 840 840 840 840 840 840 840 840 840

Burner Pressure - mbar

Burner Pressure - in. w.c. 2.4 4.0 4.2 4.3 4.8 4.8 5.0 5.1 6.0

*Gas Rate - m³/hr

Gas Rate - ft³/hr 75.70 99.30 124.50 144.70 175.00 198.50 223.80 249.00 299.50

Gas Valve Type

Part No

LPG GAS

Injector Size

Injec tor ma rking N/A 250 250 250 250 250 250 250 250

Propane Inlet Pressure - mbar N/A 37.0 37.0 37.0 37.0 37.0 37.0 37.0 37.0

Propane Inlet Pressure - in. w.c. N/A 14.8 14.8 14.8 14.8 14.8 14.8 14.8 14.8

*Propane Gas Rate m³/hr N/A 1.11 1.39 1.62 1.96 2.22 2.50 2.79 3.35

Propane Gas Rate kg/hr N/A 2.11 2.64 3.07 3.72 4.22 4.75 5.29 6.36

BUTANE

Butane Inlet Pressure - mbar

Butane Inlet Pressure - in. w.c. N/A 11.6 11.6 11.6 11.6 11.6 11.6 11.6 11.6

*Butane Gas Rate M³/hr

Butane Gas Rate kg/hr N/A 2.15 2.69 3.13 3.78 4.29 4.84 5.39 6.48

Gas Valve Type N/A S.I.T. Nova S.I.T. Nova S.I.T. Nova S.I.T. Nova S.I.T. Nova S.I.T. Nova S.I.T. Nova S.I.T. Nova

Part No

Gas Connection Size R ½R ½R ½R ½R ½R ½R ½R ½R ½

60 80 100 120 140 160 180 200 240

76770 100654 126244 146716 177424 201308 226898 252488 303668

17.78 23.31 29.23 33.97 41.08 46.61 52.54 58.46 70.31

5.9 10 10.6 10.7 12.0 12.0 12.5 12.8 14.9

2.14 2.81 3.53 4.10 4.96 5.62 6.34 7.05 8.48

S.I.T. Nova S.I.T. Nova S.I.T. Nova S.I.T. Nova S.I.T. Nova S.I.T. Nova S.I.T. Nova S.I.T. Nova S.I.T. Nova

0.820.054 0.820.054 0.820.054 0.820.054 0.820.054 0.820.054 0.820.054 0.820.054 0.820.054

L 431 L 431 L 431 L 431 L 431 L 431 L 431 L 431 L 431

N/A 7 x .54 7 x .54 7 x .54 7 x .54 7 x .54 7 x .54 7 x .54 7 x .54

N/A 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0

N/A 0.84 1.06 1.23 1.49 1.69 1.90 2.12 2.55

0.820.054 0.820.054 0.820.054 0.820.054 0.820.054 0.820.054 0.820.054 0.820.054

(No Regulator) (No Regulator) (No Regulator) (No Regulator) (No Regulator) (No Regulator) (No Regulator) (No Regulator)

L 431 L 431 L 431 L 431 L 431 L 431 L 431 L 431

*Gas rates corrected to standard conditions 1013.25 mbar 15°C

Page 16

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

4.5 Technical Data Table - CUHA/A, CUHB/A, CUHC/A and CUHD/A Automatic Ignition Range

Appliance Category II

2H3+

Natural Gas Inlet Pressure 20 mbar (17 - 25) Propane Inlet Pressure 37 mbar (25-45) Butane Inlet Pressure 29 mbar (20-35)

AUTOMATIC IGNITION

MODEL REFERENCE

Heat Input Gross cv

Btu/hr

Heat Input Net cv

Btu/hr

Approx. Heat Output

Btu/hr

Number of Burners

NATURAL GAS

Injector size 7 x .94 7 x .94 7 x .94 7 x .94 7 x .94 7 x .94 7 x . 94 7 x .94 7 x .94 7 x . 94 7 x .94 7 x .94 7 x .94

Injector marking

Burner Pressure

mbar

Burner Pressure

in. w.c.

*Gas Rate - m³/hr

Gas Rate - ft³/hr 75.70 99.30 124.50 144.70 175.00 198.50 223.80 249.00 299.50 346.60 370.20 420.60 471.10

Gas Valve Type

Part No

LPG GAS

Injector Size N/A 7 x .54mm 7 x .54mm 7 x .54mm 7 x .54mm 7 x .54mm 7 x .54mm 7 x .54mm 7 x .54mm 7 x .54mm 7 x .54mm 7 x .54mm 7 x .54mm

Injector marking

PROPANE

Inlet Pressure - mbar N/A 37.0 37.0 37.0 37.0 37.0 37.0 37.0 37.0 37.0 37.0 37.0 37.0

Inlet Pressure - in. w.c. N/A 14.8 14.8 14.8 14.8 14.8 14.8 14.8 14.8 14.8 14.8 14.8 14.8

*Propane Rate - m³/hr

Propane Rate - kg/hr N/A 2.11 2.64 3.07 3.72 4.22 4.75 5.29 6.36 7.36 7.86 8.93 10.01

BUTANE

Inlet Pressure - mbar

Inlet Pressure - in. w.c. N/A 11.6 11.6 11.6 11.6 11.6 11.6 11.6 11.6 11.6 11.6 11.6 11.6

*Butane Rate - m³/hr N/A 0.84 1.06 1.23 1.49 1.69 1.90 2.12 2.55 2.95 3.15 3.58 4.01

Butane Rate - kg/hr N/A 2.15 2.69 3.13 3.78 4.29 4.84 5.39 6.48 7.50 8.00 9.10 10.19

Gas Valve Type

Part No L 413 L 413 L 413 L 413 L 421 L 421 L 421 L 421 L 421 L 421 L 059B L 059B

Gas Connection

Size

/A 60 /A 80 /A 100 /A 120 /A 140 /A 160 /A 180 /A 200 /A 240 A 280 /A 300 /A 340 /A 380

22.5 29.5 37 43 52 59 66.5 74 89 103 110 125 140

76770 100654 126244 146716 177424 201308 226898 252488 303668 351436 375320 426500 477680

20.3 26.6 33.3 38.7 46.9 53.2 59.9 66.7 80.2 92.8 99.1 112.6 126.1

69170 90689 113746 132191 159859 181379 204435 227492 273605 316644 338163 384277 430390

17.78 23.31 29.23 33.97 41.08 46.61 52.54 58.46 70.31 81.37 86.90 98.75 110.60

60648 79517 99733 115906 140165 159033 179249 199466 239898 277634 296503 336935 377367

4 4 5 6 7 8 9 10 12 14 15 17 19

840 840 840 840 840 840 840 840 840 840 840 840 840

6.9 10.6 10.2 10.0 10.6 10.5 10.5 10.5 11.5 11.0 12.1 11.0 11.4

2.8 4.2 4.1 4.0 4.2 4.2 4.2 4.2 4.6 4.4 4.84 4.4 4.56

2.14 2.81 3.53 4.10 4.96 5.62 6.34 7.05 8.48 9.81 10.48 11.91 13.34

S.I.T.

Tandem

0.830.033 0.830.033 0.830.033 0.830.033 0.830.033 0.822.117 0.822.117 0.822.117 0.822.117 0.822.117 0.822.117

L 411 L 411 L 411 L 411 L 411 L 421 L 421 L 421 L 421 L 421 L 421 L 059B L 059B

N/A 250 250 250 250 250 250 250 250 250 250 250 250

N/A 1.11 1.39 1.62 1.96 2.22 2.50 2.79 3.35 3.88 4.14 4.70 5.27

N/A 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0 29.0

N/A

R ½R ½R ½R ½R ½R ¾R ¾R ¾R ¾R ¾R ¾ R 1 R 1

S.I.T.

Tandem

S.I.T.

Tandem

0.830.020 0.830.020 0.830.020 0.830.020 0.822.117 0.822.117 0.822.117 0.822.117 0.822.117 0.822.117

(No

Regulator)

S.I.T.

Tandem

S.I.T.

Tandem

(No

Regulator)

S.I.T.

Tandem

S.I.T.

Tandem

(No

Regulator)

S.I.T.

Tandem

S.I.T.

Tandem

(No

Regulator)

S.I.T. Nova

S.I.T. Nova S.I.T. Nova S.I.T. Nova S.I.T. Nova S.I.T. Nova S.I.T. Nova Honeywell Honeywell

(No

Regulator)

S.I.T.

Nova

(No

Regulator)

S.I.T. Nova

(No

Regulator)

S.I.T. Nova

(No

Regulator)

S.I.T. Nova

(No

Regulator)

S.I.T. Nova

(No

Regulator)

Honeywell Honeywell

VR 420

AB 1002

VR 420

AB 1002

Regulator)

(No

VR 420

AB 1002

VR 420

AB 1002

(No

Regulator)

*Gas rates corrected to standard conditions 1013.25 mbar 15°C

Page 17

SECTION 4: SPECIFICATIONS

4.6 Gas Controls - Automatic Ignition

Gas control valves fitted are dependent upon the model, each giving the same control elements as follows. See Page 40, Figure 16 through Page 41, Figure 19.

4.6.1 Main Gas Burner

The main gas valve contains

• Gas pressure regulator.

• Two automatic shut off valves.

When commissioned as defined on Page 38, Section 11 through Page 43, Section 11.12 the valves will have a step opening operation on the main gas. Settings of the valves are given on Page 42, Section

11.4.2 and in the tables on Page 9, Section 4.4 through Page 10, Section 4.5.

4.6.2 Pilot Gas Burner (Models 340 to 380 only)

There is one solenoid valve to control the pilot burner gas supply which is designed to operate at inlet pressure.

4.7 Gas Controls - Manual Ignition

The gas valve contains

• Main gas regulator.

• Safety gas valve controlled by the thermocouple.

• Solenoid valve to operate the main gas.

• Manual control knob and piezo electric igniter.

4.8 Main Fan

The main air moving fan(s) fitted to these heaters are operated automatically by the fan thermostat within the combination fan/limit thermostat. When suitably connected to site wiring (See Page 21, Section 10) the fan(s) may also be used for distributing unheated air.

Fan Thermostat

The fan thermostat controls the operation of the main fan during the heater operation. It also ensures that the main fan continues to run after the burner turns off. 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.

4.9.2 Second Limit Thermostat

This is a manual reset device - See Page 7, Section

4.2.

NOTE: On CUHB and CUHC models 340 and 380 there are two of these fitted. To reset this thermostat:

1. Remove the screw on cover of the thermostat where it protrudes from the cabinet side.

2. Push in the button in the centre of the thermostat.

3. Replace the cover.

4.10 Thermocouple Interrupter Relay

Manual ignition heaters are fitted with a thermocouple interrupter relay to interface between the limit thermostats and the thermocouple. The limit thermostats provide a constant voltage to the coil connections making the relay permanently energised. On interruption of the electrical supply to the relay, the contact opens causing the safety valve to close. The pilot will then need to be manually lit.

4.9 Limit Thermostats

There are two limit thermostats on these heaters to protect them from overheating, should the fan fail. One is within the combination thermostat and the second is on the side of the heater towards the rear of the heater. NOTE: On models 340 and 380 B & C versions there is a further secondary limit thermostat protecting the third fan unit.

4.9.1 Honeywell Combination Fan/Limit Thermostat (See Page 12, Figure 5)

The combination fan/limit thermostat is a dual function control and safety device. Two of these are fitted to CUHD versions, the second one is on the inlet spigot at the rear of the heater.

4.11 Automatic Ignition - Burner Control Box

4.11.1 Description of Burner Control Box

The fully automatic gas burner fitted to all CUHA/A, CUHB/A, CUHC/A and CUHD/A models is controlled by a Satronic DKG 972 or a Honeywell S 4563 control box. This control ensures the safe start and stop sequence and also monitors the safe presence of a flame. See Page 56, Figure 26.

Page 18

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

Figure 5: Combination Fan/Limit Thermostat

WARNING

Fire Hazard

Break-off link must be removed from replacement thermostat.

Failure to follow these instructions can result in death, injury, property damage or product damage.

Dial

Limit Hand

Fan On Hand

Fan Off Hand

Fan Terminals

Manual Fan Switch

(White)

Figure 6: Honeywell Control

Honeywell S4563 C Control Models 60 -300

Fan & air pressure switch Connections ( linked out)

Supply, Remote lockout signal & reset Main Gas Valve

Push Screwdriver in and hold to release

Push in Lock

Wire to Controlled Equipment

Limit Stat

Manual

Reset Button (Red)

Limit Terminals

BREAK-OFF LINK MUST BE REMOVED

Honeywell S4563 B Control Models 340 -380 only

Supply, Remote lockout signal & reset

Start Gas Valve

Flame Probe

6.3 x 0.8

S 4563 C Honeywell

Earth

4.8 x 0.8

Ignition

2.8 x 0.5

Main Gas Valves

Flame Probe

6.3 x 0.8

S 4563 B Honeywell

Earth

4.8 x 0.8

Ignition

2.8 x 0.5

Page 19

SECTION 5: HEATER INSTALLATION

10 mm Drop Rod

Nut

Washer

Nut

10 mm Drop Rod

Washer

Nut

Unistrut

Channel Nut

Cone Point

Set Pin

Window

Clamp

Unistrut

SECTION 5: HEATER INSTALLATION

5.1 General

Heaters are designed for installation where by the bottom panel of the heater is between 2.75m and

3.75m above the floor.

5.2 Handling

All CUH range heaters are supplied secured to a wooden pallet and shrink wrapped. Use the pallet to support the heater during handling and installation.

Figure 7: Suspension Methods

5.3 Shelf Mounting and Suspension

WARNING

Suspension Hazard

Support heater at all four corners on the lower edge of the side panels.

Use 10mm drop rod minimum.

Failure of the supports can result in death, injury or property damage.

The bottom panel is not intended to support the weight of the heater. For typical suspension See Page 13, Figure 7.

Lower Edge

Page 20

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

Over 2 m

use Guy Wires

Roof

Wall

Use adequate support to prevent heater from carrying the weight of the flue.

SECTION 6: FLUE INSTALLATION

6.1 Flue Installation

Flues must be correctly sized for the model. See

WARNING

Page 6, Section 4.1. Flues should be assembled as on Page 5, Figure 2, on Page 5, Figure 3 and Page 14, Figure 8 through Page 15, Figure 11. The joints

between the flue and the roof or wall must be properly sealed. If the flue passes through a wall or ceiling of combustible material it must be enclosed

Fire Hazard

Some objects will catch fire or explode when placed close to heater.

Keep all flammable objects, liquids and vapours the required distance away from the heater.

Failure to follow these instructions can result in death, injury and property damage.

by a sleeve of non-combustible material and be separated from the sleeve by at least a 25 mm air gap.

Flues must be adequately supported so that the heater does not bear the weight of the flue.

For straight and offset flue termination See Page 5, Figure 2 and Figure 3.

90° bends and horizontal pipe must not be used in flues. 135° bends are used to offset the flue as in

Figure 3.

Figure 8: Guy Wire Figure 9: Socket Direction

Flue

Terminal

Male spigot

facing up.

Roof

Conversion Collar -

last joint below

the roof line.

Masterflash

soaker flashing

or Rain Collar.

Metal Sleeve

Screws,

four typical.

Clamp Ring

Male spigot

facing down.

Page 21

SECTION 6: FLUE INSTALLATION

Figure 10: Flue and Roof Detail Figure 11: Flue and Heater Spigot Joint Detail

Screws,

four typical.

Clamp ring

If it is necessary to cut any section of flue, the cut is made at the bottom of the lowest section where it connects to the heater.

Roof

Rain Collar

Seal Rain Collar

joint with silicon

sealer provided

Heat Sealed

Flash Band

Screws

Roof Plate

Secure Bolts

Stainless Steel Roof Tidy Plate

Heater

Spigot

Fire

Cement

Heat

Resistant

Rope

Page 22

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

6.2 Models 340 and 380 only

The models 340 and 380 heaters are provided with two outlet spigots on top of the heater and a flue assembly to combine these two flue outlets into a single vertical flue.

For flue assembly See Page 16, Step 6.2.1 and Step 6.2.2.

The remainder of the vertical flue is then installed from the spigot at the top of the assembly in accordance with the instructions for all other models.

Step 6.2.1 Flue assembly for models 340 and 380 only.

Branch Arms

Bend

Step 6.2.2 Fitting Flue assembly to heater for models 340 and 380 only.

Fit flue assembly to heater.

Dim. F

Screws

Dim. E

Dimension F = 372 mm Dimension E = 405 mm

Seal to spigots

using fire cement

and heat

resistant rope.

Page 23

SECTION 7: AIR SUPPLY

7.1 Air Supply

It is important to ensure that there is adequate air supply at all times for both combustion and heating requirements.

7.1.1 Isolated Equipment Rooms

Ventilation must prevent the isolated equipment room temperature from exceeding 32°C as well as prevent any negative air pressure within the room. See Page 19, Figure 12. Any isolated equipment room containing air heaters will require permanent air vents direct to outside air in compliance with local codes

Where natural ventilation is used, suitable permanent openings at low and high level, communicating directly with the outside air, must be provided.

Where mechanical ventilation is used, extract rate must be 5% - 10% less than the inlet rate. The mechanical ventilation must be interlocked with the burner on the CUH heater.

SECTION 7: AIR SUPPLY

7.1.2 Heaters Installed Within the Heated Space

Where the volume of the heated space is greater than 4.7 m

per kilowatt of total rated heat input and the air change rate is at least 0.5/h, additional high and low level ventilation will not be required.

For a building having an air change rate less than

0.5/h, low level ventilation will be necessary in accordance with local codes.

7.2 Building Ventilation

Where ventilation is required air must be taken from an outside point where it is not likely to be contaminated.

Page 24

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

SECTION 8: OPTIONAL HEATER CONFIGURATIONS

8.1 Distribution Ductwork for CUHB, CUHC and CUHD Heaters

CUHC range heaters have the fans enclosed so that the heater may be connected to inlet ducting.

8.1.1 CUHD Heaters

For CUHD heaters it is essential that the airflow in the duct system is at least that specified in the Data Sheet on Page 8, Section 4.3 and in the correct

direction across the heat exchanger as indicated by CUHD range heaters are supplied with inlet and outlet duct spigots for mounting the heater into a customer designed duct system for use with an external fan system.

the arrow on the heater. Higher air flows are

permitted, but will cause a lower exiting air

temperature. It is recommended that the fan is

positioned to blow the air through the heat

exchanger. It is important when ducted systems are required that only the spigots and flanges produced and fitted by Roberts-Gordon are used at the heater. See Page 5, Figure 4 and Page 19, Figure 13. It is recommended that flexible duct connectors are

The duct must be designed as described on Page

18, Section 8.1 and on Page 5, Figure 4 to ensure

that there is a homogenous air flow across the

whole of the heat exchanger. used to reduce duct born noises.

Failure to provide a suitable air flow properly When installing heaters onto ducting use a 60 second time delay relay to force the fan to run.

distributed across the heat exchanger will reduce

the life of the heat exchanger. Do not rely on the fan thermostat to turn it on. See suggested scheme on Page 22, Figure 10.3. Any such device must be in parallel with the fan thermostat so that the fan run-on operation will still operate. CUHD heaters are fitted with two combination thermostats, at the front and in the rear

The fan motor or its control must contain a method

of overload protection. When installed remote from

the heater the fan must be supplied via a local

electrical isolator positioned and properly labeled to

prevent inadvertent operation. inlet spigot for this purpose

Contact Roberts-Gordon Europe Ltd. Design Department for recommendations regarding duct resistance and design. Tel: +44 (0) 1902 494425

Page 25

Figure 12: Heaters installed in isolated equipment rooms.

SECTION 8: OPTIONAL HEATER CONFIGURATIONS

High level

Flue

ventilation

Duct distribution system or discharge to heated space.

AIRFLOWAIRFLOW

Max Temperature 32° C Room air pressure must not be negative.

Wall

ventilation

Outside

Figure 13: CUH C or D Heaters with Inlet/Outlet Duct Spigots and Flange.

Return air duct from heated space or fresh air from outside

Low level

Wall

AIRFLOW

Inlet Duct Spigot

on CUHC and CUHD

AIRFLOW

Outlet Duct Spigot

on CUHD and special

order CUHB and CUHC

ROBERTS GORDON

produced flange (30 mm)

Inlet and Outlet joints sealed at factory

Page 26

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

SECTION 9: GAS PIPING

WARNING

Fire Hazard

Connect gas supply according to Figure 14, below.

Gas can leak if not installed properly.

Failure to follow these instructions can result in death, injury or property damage.

A gas meter is connected to the service pipe by the Gas Supply Company. An existing meter should be checked, preferably by the Gas Supply Company to ensure that the meter is adequate for the rate of gas supply required.

Connect the heater to the gas supply ensuring that

the final connections are as follows:

• Gas supply pipe work is run in medium or heavy gauge tubing to National Standards terminating as shown on Page 20, Figure 14.

• An isolating valve and union connection should be used and fitted into the supply adjacent to the heater.

• For suspended heaters use an approved metal flexible connection between the isolating valve and the heater. To reduce pressure loss, use one pipe size larger that the supply gas pipe.

IMPORTANT - the complete installation must be purged and tested for gas soundness in accordance with National Standards.

L.P.G. For L.P.G. applications each heater must be provided with the gas inlet pressure closely controlled to 37 mbar for Propane (G31) or 29 mbar for Butane (G30). A suitable regulator controlling the inlet pressure to each heater will be required for this.

Figure 14: Gas Connection with Stainless Steel Flex Connector

Hold gas nipple securely

with pipe wrench when attaching the flex gas connector.

Do not twist flexible

gas connector.

Stainless Steel Flex

Gas Connector

(for suspended heaters)

Insure all joints are

gas tight.

Gas Service Cock

Union Connection

Page 27

SECTION 10: WIRING AND ELECTRICAL INFORMATION

10.1 Electrical Supply

All heater models need a constant 230 volt 50 Hz single phase supply connected to terminals L, N & Earth. Polarity "L & N " must be correct. For automatic ignition versions the voltage between N and Earth must not exceed 15v. All heaters and controls must be correctly earthed.

10.2.2 Siting Room Thermostats or Roberts-Gordon Control

A room thermostat or Roberts-Gordon control should be mounted on a wall or column at a height of approximately 1.5 metres from the floor to measure the ambient temperature. It should be clear of cold draughts and the direct path of warm air from the heater.

All external wiring must comply with the relevant local codes. External controls must have the same constant 230v 50Hz supply.

10.2.3 Remote Frost Thermostat

Where a frost thermostat is required to override the operation of a time switch during its "off" periods,

An isolator with a contact separation of at least 3 mm on all poles must be installed adjacent to, but not fixed to the heater to disconnect all supplies to the heater and any remote control.

connect to terminals 2 and 3 in the main terminal block on the side of the heater. Locate within the heated space adjacent to the most vulnerable equipment that requires protection. See Page 22, Section 10.3.

The final connection to the heater should be made in flexible conduit to the main terminal block on the side of the heater using 1 mm

cable on all models.

10.2.4 Remote Fan Controls

The fan will operate automatically providing there is a constant 230v supply to the main terminals.

Models Fuse Size

A switch or control wired between terminals L & 1 in the terminal block at the side of the heater will allow

CUHA, CUHA/A all models 5 Amp.

external control of the fan(s). The fan may be controlled to operate continuously from an external control, with the burner cycling on

CUHB, CUHB/A CUHC, CUHC/A up to 300 10 Amp.

and off, providing that the fan run-on at close down is not impaired.

SECTION 10: WIRING AND ELECTRICAL INFORMATION

CUHB, CUHB/A, CUHC, CUHC/A from 340 to 380 20 Amp.

CUHD and CUHD/A models must have the external fan, or its control connected to Terminal 1 so that the fan run-on function at close down operates correctly.See Page 22, Section 10.4.

WARNING

Electrical Shock Hazard

Disconnect electrical power before servicing.

Failure to follow these instructions can result in death or electrical shock.

10.2 Remote Controls

The heaters are designed to be operated by controls installed remote from the heater. See Page 22, Section 10.3.

10.2.1 Burner Controls

Controls to operate the burner must be voltage free contacts connected between terminals 2 & 3 of the main terminal block on the side of the heater.

Page 28

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

10.3 CUH Individual Controls (all models)

Minimum Control

Heater Terminals

230v Room Thermostat

230v 50Hz Supply

Normal Control

Heater Terminals

Optional Fan Controls

Heater Terminals Heater Terminals

Remote fan switch

Time/Temperature

RDW 1532

230v 50Hz Supply

Time Switch

230v 50Hz

Frost Thermostat

Room Thermostat

For CUHB, CUHC or CUHD Heaters Scheme to force fan to run with burner operation.

230v 50Hz Time Delay or Standard Relay

Controls

10.4 CUHD External Motor Alternative Wiring (all models)

Single Phase Motor with load over 7 Amps

NL 1 2 3

230v Thermostat

230v

Single Phase Motor with load over 7 Amps

overload protection must 230v 50Hz supply

be provided at the motor

or contactor

Contactor or relay

RDW 1565

Three Phase motor

NL 1 2 3

400v 50Hz 3N Supply

LLL

230v Thermostat

230v

Contactor or relay

400v 3 phase motor

overload protection must be provided at the motor or contactor

Page 29

10.5 CUHA Wiring Diagram

230v 50Hz supply

MANUAL IGNITION

MAIN TERMINALS

Combination

fan/limit

thermostat

red/white

red

SECTION 10: WIRING AND ELECTRICAL INFORMATION

Second limit thermostat

Fan

white

Limit

blue

brown

230v remote room thermostat

Thermocouple

interrupter

relay

brown

site wiring

RDW 1518

NOTE: Second fan on models CUHA 200 & 240. The second fan terminals and capacitor may be in a separate terminal box.

10.6 CUHB & CUHC Wiring Diagram (60-160)

MANUAL IGNITION

RDW 1652

red/white

brown

Multifunctional

gas valve

blue

fan capacitors

brown

Motor

Fan

black

blue

brown

white

black

blue

230v room

thermostat

230v 50Hz

supply

site wiring

red

limit thermostat

Thermocouple interrupter relay

brown brown

white/red

Second

blue

brown

white

white/red

black

blue

red

white

green/yellow

High

Medium

Low

Neutral

red

white/red

brown

blue

Multifunctional

gas valve

limit

fan combination

thermostat

NOTE:

Consult Page 8, Section 4.3 for correct speed setting for model. Consult Roberts Gordon before changing speed setting.

Page 30

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

10.7 CUHB & CUHC Wiring Diagram (180-240)

MANUAL IGNITION

RDW 1651

changing speed setting.

site wiring

230v 50Hz Supply

correct speed setting for model.

Consult Roberts Gordon

before

NOTE:

Consult Page 8, Section 4.3 for

blue

230v room thermostat

MAIN TERMINALS

brown

white/red

brown

white/red

brown

Multifunctional

gas valve

brown

Thermocouple

interrupter

relay

blue

white/red

combination

thermostat

fan

red

limit

Limit stat

Second

white

Fan 1

Fan 2

green/yellow

white

red

blue

black

green/yellow

white

red

blue

black

Neutral

Low

Medium

High

Neutral

Low

Medium

High

12345678910

blue

yellow

blue

yellow

Motor

contactor

230v coil

red

Page 31

10.8 CUHD Wiring Diagram (all models)

MANUAL IGNITION

SECTION 10: WIRING AND ELECTRICAL INFORMATION

230v 50Hz supply

Fan motor

Max load 7Amps

230v thermostat

MAIN TERMINALS

blue

brown

Thermocouple interrupter relay

red

red/white

orange/white

Combination fan/limit thermostat

Flame probe

Fan

Limit

orange

red

Secondary limit thermostat

red/white

white

Rear combination fan/limit thermostat

Fan

Limit

RDW 1563

brown

Multifunctional gas valve

blue

orange/white

orange

red/white

Site wiring

Page 32

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

10.9 CUHA/A Wiring Diagram (60-240) Satronic

AUTOMATIC IGNITION

230v 50Hz

site wiring

Supply

230v room

thermostat

Lockout

reset

Lockout

MAIN TERMINALS

fan

blue

Second fan motor

for models 200 and over

white/red

black

brown

black

brown

white

Capacitors

white

pink

thermostat

white

Combination

limit

Second

limit stat

Spark

generator

red

brown

white

blue

black

white/brown

brown

grey

N FN/660/3/06

mains filter

blue

Schaffner

blue

(red)

black

OUT

Lockout

blue

violet

(green)

Heat ON

Remote Reset

Satronic DKG 972 Mod 03

control box

RDW 1800

probe

Flame

GV1

GV2

Page 33

10.10 CUHA/A Wiring Diagram (280-300) Satronic

AUTOMATIC IGNITION

RDW 1801

MAIN TERMINALS

white/brown

white

red

Combination

thermostat

blue

grey

Limit

black

white

Second limit stat

Schaffner FN/660/3/06

mains filter

OUT

Violet

Lockout

230v room thermostat

Lockout reset

heat ON (green)

Lockout (red)

SECTION 10: WIRING AND ELECTRICAL INFORMATION

Satronic DKG 972 Mod 03 control box

Remote reset

blue

black

brown

black

brown

spark generator

pink

GV2

GV1

flame probe

white/red

230v 50Hz Supply

site wiring

fan

white/red

blue

10.11 CUHA/A Wiring Diagram (340-380) Satronic

AUTOMATIC IGNITION

RDW 1802

MAIN TERMINALS

Lockout

230v room thermostat

Lockout reset

white/brown

blue

red

black

grey

Limit Combination thermostat

Schaffner

FN/660/3/06

mains filter

white

Second limit stat

OUT

heat ON

(green)

Lockout

violet

(red)

Capacitors

white

Satronic DKG 972 Mod 10 control box

Remote reset

blue

brown

black

brown

spark generator

blue

pink

blue

GV3

GV2

GV1

black

blue

brown

Fan Motors

Flame probe

black

blue

brown

230v 50Hz supply

site wiring

Capacitors

white/red

fan

white/red

blue

white

black

blue

brown

Fan Motors

black

blue

brown

Page 34

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

10.12 CUHB/A & CUHC/A Wiring Diagram (60-160) Satronic

AUTOMATIC IGNITION

NOTE:

Consult Page 8, Section 4.3 for

correct speed setting for model.

Consult Roberts Gordon before

changing speed setting.

white

red

Fan 1

blue

black

green/yellow

site wiring

Neutral

Low

Medium

High

blue

Supply

230v 50Hz

white/red

fan

white/red

230v room

thermostat

Lockout

reset

RDW 1803

Lockout

MAIN TERMINALS

Limit

Combination

thermostat

Second

Limit stat

blue

red

white

white/brown

mains filter

IN OUT

Schaffner

FN/660/3/06

grey

black

GV2

violet

Lockout

(red)

blue

heat ON

(green)

Satronic DKG 972 Mod 03

control box

blue

brown

flame

probe

black

GV1

pink

brown

spark

generator

Page 35

10.13 CUHB/A & CUHC/A Wiring Diagram (180-300) Satronic

AUTOMATIC IGNITION

SECTION 10: WIRING AND ELECTRICAL INFORMATION

NOTE:

Consult Page 8, Section 4.3 for

correct speed setting for model.

Consult Roberts Gordon before

changing speed setting.

Fan 1

green/yellow

white

red

site wiring

Neutral

Low

230v 50Hz

Supply

230v room

thermostat

Lockout

reset

RDW 1804

Lockout

MAIN TERMINALS

blue

white/red

fan

blue

limit

combination

thermostat

Limit stat

white/red

red

Second

red

white

blue

white/brown

black

grey

Fan 2

blue

black

green/yellow

white

red

blue

black

Medium

High

Neutral

Low

Medium

High

910

yellow

blue

yellow

Schaffner

FN/660/3/06

mains filter

OUT

brown

GV1

blue

GV2

Motor

contactor

230v coil

pink

spark

generator

brown

flame

probe

black

violet

Lockout

(red)

blue

heat ON

(green)

Satronic DKG 972 Mod 03

control box

Remote Reset

Page 36

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

10.14 CUHB/A & CUHC/A Wiring Diagram (340-380) Satronic

AUTOMATIC IGNITION

230v room

thermostat

combination

thermostat

limit

site wiring

NOTE:

Consult Page 8, Section 4.3 for

correct speed setting for model.

Consult Roberts Gordon before

changing speed setting.

230v 50Hz

Supply

white/red

fan

red

Lockout

RDW 1807

Lockout

reset

white

grey

MAIN TERMINALS

Fan 1

Fan 2

Fan 3

green/yellow

white

red

blue

black

green/yellow

white

red

blue

black

green/yellow

white

red

Neutral

Low

Medium

High

Neutral

Low

Medium

High

Neutral

Low

blue

6789

10 11 12 13

blue

yellow

blue

yellow

230v coil

pink

Limit stat

white/red

red

Motor

contactor

generator

Second

limit stat

blue

spark

brown

white

Extra

white/brown

mains filter

FN/660/3/06

Schaffner

OUT

violet

Lockout

(red)

blue

GV3

GV1

brown

black

GV2

brown

(green)

black

heat ON

remote

reset

Satronic DKG 972 Mod 10

control box

blue

black

Medium

High

14 15

flame

probe

Page 37

10.15 CUHD/A Wiring Diagram (60-300) Satronic

SECTION 10: WIRING AND ELECTRICAL INFORMATION

Lockout N

230v room thermostat

Fan motor max load 7 Amps

230v 50Hz Supply

MAIN TERMINALS

Lockout reset

red

AUTOMATIC IGNITION

heat ON (green)

black

grey

white/brown

blue

limit

front combination thermostat

white/red

fan

white

secondary limit stat

orange/white

Schaffner

FN/660/3/06

mains filter

violet

OUT

red

limit

orange/white

Rear combination thermostat

fan

Lockout (red)

blue

Satronic DKG 972 Mod 03 control box

blue

brown

GV2

GV1

brown

spark generator

Flame probe

pink

RDW 1806

10.16 CUHD/A Wiring Diagram (340-380) Satronic

AUTOMATIC IGNITION

MAIN TERMINALS

black

grey

white/brown

red

Fro Combination Thermostat

blue

white

limit

white/red

fan

secondary limit stat

orange/white

Schaffner FN/660/3/06

Mains Filter

Lockout

230v room thermostat

Fan motor max load 7 Amps

230v 50Hz Supply

Lockout reset

violet

OUT

limit

Orange/white

Rear Combination Thermostat

fan

red

heat ON (green)

Lockout (red)

Satronic DKG 972 Mod 10 control box

remote

reset

blue

brown

black

brown

spark generator

pink

RDW 1805

GV3

GV2

GV1

Flame probe

site wiring

Page 38

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

10.17 CUHA/A Wiring Diagram (60-240) Honeywell

AUTOMATIC IGNITION

site wiring

Supply

blue

for models 200

and over

Second fan motor

230v 50Hz

white/red

fan

black

brown

black

brown

thermostat

230v room

Lockout

Remote

Lockout reset

MAIN TERMINALS

thermostat

Combination

limit

red

white

white/brown

blue

grey

Lockout reset

white

Capacitors

white

limit stat

where fitted

white

Second

mains filter

Lockout

(red)

violet

Valve

Main Gas

RDW 1800 /A

OUT

Heat ON

(green)

S 4563 C Honeywell

Probe

Flame

Page 39

10.18 CUHA/A Wiring Diagrams (280-300) Honeywell

SECTION 10: WIRING AND ELECTRICAL INFORMATION

RDW 1801/A

AUTOMATIC IGNITION

Lockout

reset

Lockout

white

Second limit stat

white/red

blue

Remote Lockout

230v room thermostat

230v 50Hz Supply

site wiring

reset

Lockout

MAIN TERMINALS

grey

brown

white

red

combination

thermostat

white/red

black

blue

limit

fan

10.19 CUHA/A Wiring Diagram (340-380) Honeywell

(red)

mains filter

Main Gas Valve

OUT

where fitted

Capacitors

white

flame probe

S 4563 C Honeywell

Heat On

(green)

Fan Motors

black

blue

brown

black

blue

brown

RDW 1802/A

Remote Lockout

reset

Lockout

230v room thermostat

230v 50Hz Supply

site wiring

MAIN TERMINALS

black

grey

brown

white

blue

red

combination

thermostat

white/red

AUTOMATIC IGNITION

(red)

mains filter

Start Gas Valve

where fitted

white

OUT

Capacitors

white

limit

fan

Lockout

reset

white

second

limit stat

Lockout

white/red

blue

S4563 B Honeywell

Heat On

(green)

black

blue

Fan Motors

brown

Main Gas Valve

brown

black

blue

Flame Probe

Page 40

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

10.20 CUHB/A & CUHC/A Wiring Diagram (60-160) Honeywell

AUTOMATIC IGNITION

site wiring

Green/Yellow

white

red

blue

black

Supply

230v 50Hz

white/red

fan

Neutral

Low

Medium

High

correct speed setting for model.

Consult Roberts Gordon before

changing speed setting.

NOTE:

Consult Page 8, Section 4.3 for

white/red

blue

thermostat

230v room

Lockout

Lockout reset

Remote

MAIN TERMINALS

Combination

thermostat

limit

red

blue

white

white/brown

grey

Lockout reset

limit stat

where fitted

white

Second

mains filter

OUT

(red)

Lockout

Valve

Main Gas

RDW 1803/A

Heat ON

(green)

S 4563 C Honeywell

Flame

Probe

Page 41

SECTION 10: WIRING AND ELECTRICAL INFORMATION

10.21 CUHB/A & CUHC/A Wiring Diagram (180-300) Honeywell

AUTOMATIC IGNITION

NOTE:

Consult Page 8, Section 4.3 for correct

speed setting for model.

Consult Roberts Gordon before

changing speed setting.

green/yellow

white

Fan 1

red

blue

site wiring

Neutral

Low

Medium

Lockout

Remote Lockout

RDW 1804/A

Supply

230v 50Hz

thermostat

230v room

reset

MAIN TERMINALS

fan

blue

white/red

blue

Yellow

thermostat

white/red

combination

limit

Limit stat

Second

red

white

blue

white/brown

white

grey

black

Lockout

reset

Lockout

(Red)

Fan 2

black

green/yellow

white

red

blue

black

High

Neutral

Low

Medium

High

blue

230v coil

contactor

Motor

mains filter

where fitted

OUT

Main Gas

Valve

Yellow

(Green)

Heat ON

109

S 4563 C Honeywell

Flame

Probe

Page 42

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

10.22 CUHB/A & CUHC/A Wiring Diagram (340-380) Honeywell

AUTOMATIC IGNITION

site wiring

230v 50Hz Supply

230v On/Off Control

Lockout

Remote Lockout

reset

TERMINAL BLOCK

NOTE:

Consult

correct speed setting for model.

Consult Roberts Gordon before

changing speed setting.

fan

Page 8, Section 4.3

for

Green/Yellow

white

Red

Blue

Black

Neutral

Low

Medium

High

white/red

white

blue

combination

thermostat

limit stat

limit

second

red

blue

white

white/brown

R1/1

230 v

white/red

Red

Lockout

Yellow

(red)

grey

black

mains filter

where fitted

OUT

blue

Lockout

reset

Green/Yellow

white

Red

Blue

Black

Green/Yellow

white

Red

Blue

Black

Neutral

Low

Medium

High

Neutral

Low

Medium

High

Motor

Contactor

1110

blue

Yellow

230v coil

(green)

Heat ON

Main Gas

Valve

Start Gas

Valve

S 4563 B Honeywell

RDW 1852

Flame

Probe

Page 43

10.23 CUHD/A Wiring Diagram (60-300) Honeywell

SECTION 10: WIRING AND ELECTRICAL INFORMATION

Remote Lockout

Lockout

230v room

thermostat

Fan motor

max load

7 Amps

230v 50Hz Supply

MAIN TERMINALS

reset

AUTOMATIC IGNITION

Main Gas

Flame Probe

Valve

Lockout

(Red)

limit

Orange/white

rear

combination

thermostat

fan

S 4563 C Honeywell

red

OUT

mains filter

Heat ON

(Green)

RDW 1806/A

black

grey

blue

limit

front

combination

thermostat

white/red

fan

Lockout

reset

white

secondary

limit stat

orange/white

red

site wiring

10.24 CUHD/A Wiring Diagram (340-380) Honeywell

AUTOMATIC IGNITION

Lockout

(Red)

limit

Orange/white

rear

combination

thermostat

fan

red

Remote Lockout

Lockout

230v room thermostat

Fan Motor

max load

7 Amps

230v 50Hz Supply

MAIN TERMINALS

reset

red

black

grey

blue

limit

front

combination

thermostat

white/red

fan

Lockout

reset

white

secondary

limit stat

orange/white

mains filter

Start Gas Valve

OUT

Flame Probe

S 4563 B Honeywell

Main Gas

Heat ON (Green)

Valve

RDW 1805/A

site wiring

Page 44

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

30 mm

minimum gap

SECTION 11: COMMISSIONING THE HEATER

Installation, service and annual inspection of heater must be done by a contractor qualified in the installation and service of gas-fired heating equipment.

Read this manual carefully before installation, commissioning, operation, or service of this equipment.

11.1 Pre Commission Checks All pre commission checks must be carried out

before lighting the heater

Ensure that the heater and all controls are suitable for the gas, pressure and electrical supply to which they are to be connected.

Turn off gas and electrical supply before maintenance.

Fan can start automatically at any time.

Failure to follow these instructions can result in severe injury or product damage.

WARNING

Cut Hazard

11.1.1 Louvers

The air delivery louvers need to be set during commissioning to give the required air distribution. To do this each louver must be twisted around its axis, raising the lower edge forward. The minimum gap is 30mm. See Figure 15.

NOTE: The louvers are designed to be set once, but will allow for occasional readjustment. Frequent adjustment will damage the axis system and require louver assembly replacement.

Figure 15: Setting Louvers

Twist

louvers

up to

open.

11.1.2 Electrical Checks

All pre commission checks must be carried out before commissioning the heater.

1. Check that all site wiring is connected in accordance with the appropriate wiring diagrams on Page 21, Section 10 through Page 37, Section 10.24.

2. Check the correct fuse size is fitted; See Page 21, Section 10.1.

11.1.3 Polarity Test

230v 50Hz AC

(must be less than 15v)

Supply

Earth

Terminal

Less Than

0.1 ohm

ohm

11.2 Gas Supply

All aspects of the gas installation including the gas meter must be inspected, tested for soundness and purged in accordance with local codes. Ensure that the air is fully purged from the heater inlet pipe up to the main gas valve inlet test nipple.

11.3 Mechanical Checks

1. Check that the fan(s) are free to run and delivery louvres are turned to give required air deflection.

Page 45

SECTION 11: COMMISSIONING THE HEATER

2. Check that the flue is installed in accordance with these instructions and local regulations.

3. Check that the settings of the Combination Fan/ Limit thermostat are correct - see below.

NOTE: The second limit thermostat is preset and sealed at the factory and is not adjustable.

Front Combination Thermostat (All Models)

Set Point 3 Limit

Set to 95°C

Set Point 2 Fan On

Set to 57°C

Set Point 1 Fan Off

Set to 38°C

120

100

C°

Rear Combination Thermostat on CUHD... Only

2. Wait one minute, then press in the control box reset button, or the remote reset button if fitted, and repeat until the pilot flame ignites.

NOTE: At the first firing of the heater it may be necessary to repeat several times to purge the remaining air from the gas train.

3. There is no adjustment for the pilot burner. Once the pilot flame has ignited it will be monitored by the flame probe and should remain on until the controls turn it off.

4. Turn off the burner at the external control and refit the electrical plug(s) to the main gas valve.

For All other Models

1. Turn off the gas isolating valve

2. Using the installed external control, turn on the burner. The automatic sequence will now begin as described on Page 56, Section 15.2.1, Fig- ure 26 and Page 44, Section 12, Figure 20.

Set Point 3 Limit

Set to 90°C

Set Point 2 Fan On

Set to 55°C

Set Point 1 Fan Off

Set to 30°C

120

100

C°

Always refit the cover and tighten the cover screw after adjustments.

To continue with the Commissioning follow Page 39, Section 11.4 for Automatic Ignition models or Page 42, Section 11.5 for Manual Ignition models. Then continue on Page 43, Section 11.6 for all appliance types

11.4 Automatic Ignition Unit Heaters

11.4.1 Before Operating the Heater

To ensure that all the controls are in safe working order, operate the heater for the first time with the main gas valve turned off.

There will be no ignition of the burner and lockout will occur, which proves the controls are operating correctly.

Models 340 & 380 (with a separate pilot)

1. Unplug the electrical plug from the main gas valves.

For Models 340 & 380

1. The pilot flame will ignite when pilot gas valve opens. If the flame does not ignite then the control will go to lockout.

Page 46

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

Figure 16: S.I.T. Tandem 0.830.033 Gas Valve (Natural gas) 0.830.020 Valve (L.P.G)

Regulator adjusting screw under cover. (NOTE: On L.P.G. heaters the Regulator Adjusting Screw must be turned fully clockwise.)

Burner Pressure

Test Point

Step Opening

Adjustment

Inlet Pressure

Test Point

Electric

Connection

Step Opening Breather Port

Gas Outlet

Gas Inlet

Description Part Number

S.I.T. Tandem 0.830.033 Automatic Ignition Natural Gas Valve L411 S.I.T. Tandem 0.830.020 Automatic Ignition LPG Gas Valve L413

Figure 17: S.I.T. Nova 0.822.177 Automatic Ignition Gas Valve

Plug for

Main Gas Valve

Inlet Pressure

Regulator (under cover)

Burner Pressure

Plug for Main

Safety Gas Valve

Pilot gas outlet of valve Blanked off

Description Part Number

S.I.T. Nova 0.822.177 Automatic Ignition Gas Valve L421

Gas Outlet

Page 47

Figure 18: S.I.T. Nova 0.820.054 Manual Ignition Gas Valve

SECTION 11: COMMISSIONING THE HEATER

Burner

Pressure

Inlet

Pressure

Manual

Control Knob

Regulator

Adjusting Screw

(under cover)

Electrical Connection

Gas

Outlet

Description Part Number

S.I.T. Nova 0.820.054 Manual Ignition Gas Valve L431

Pilot Gas Pipe

Connection

Thermocouple

Connection

Thermocouple

Interrupter

Relay Connections

Figure 19: Main Gas Valves for Models 340 and 380

The main gas control valve used on all versions of the models CUHA/A, CUHB/A, CUHC/ A and CUHD/A 340 and 380 is the Honeywell VR 420AB 1002 combination gas valve. This control contains two main safety shut off valves and burner pressure regulator.

Honeywell VR 420AB 1002 Main gas valve

Inlet flange with inlet

pressure test point

Outlet pressure test point

Outlet flange

Electrical

Connection

Pressure regulator under screw cover

Description Part Number

Honeywell VR 420AB 1002 Gas Valve L059B

Page 48

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

11.4.2 Commissioning the Gas Valves Natural Gas

11.4.2.1 Check Burner Gas Pressure

1. Remove the screw cover of the outlet (burner) pressure test point and connect a manometer.

2. With the burner firing, measure the pressure on the manometer. To adjust the burner pressure, remove the regulator cover from the valve and turn the regulator adjustment screw to set the required burner pressure as stated in the Technical Data Tables on Page 9, Section 4.4 through Page 10, Section 4.5.

NOTE: If the correct burner pressure cannot be reached, then check the inlet pressure to the valve, with the burner firing. See Technical Data Tables on Page 9, Section 4.4 through Page 10, Section 4.5 for pressure requirement.

Do not continue to adjust the regulator if the pressure is not changing.

If the inlet pressure is too low to allow correct burner setting, then gas pressure must be corrected before completing the commission.

Step Opening (Direct Main Flame Ignition)

It is important that the step opening is adjusted correctly.This ensures that the burner ignites smoothly and quietly.

S.I.T. Tandem valves Models 60 to 140

1. Turn off the burner and wait one minute for the valve to settle.

2. Remove the plastic cover from the step opening breather port. See Page 40, Figure 16. Block this port with a finger, to keep the valve at step open level. Turn on the burner again and use the step opening adjuster to set the step opening pressure to approximately 2.5 mbar.

3. Refit the plastic plug to the breather port.

11.4.3 Commissioning the Gas Valves Liquid Petroleum Gas (L.P.G.)

1. In all cases the gas valves for L.P.G either have no regulator or have the regulator set to maximum. See Page 50, Section 14.

2. Set the inlet pressure to the gas valve to 37 mbar for G31 (Propane) or 29 mbar for G30 (Butane).

NOTE: The appliance will operate safely between 25-45 mbar for G31(propane) or 20-35 mbar for G30 (butane). The correct heat input is at the specified inlet pressure. No further adjustment is necessary.

11.5 Manual Ignition Unit Heaters

All CUH manual ignition unit heaters are controlled by an S.I.T Nova 0.820.054 multifunctional gas valve. See Page 41, Figure 18.

1. Remove the electrical plug from the multifunctional gas valve to ensure that main gas cannot be released.

2. Ignite the pilot: Press in the manual control knob of the gas valve and turn counter-clock wise to the star symbol. See Page 46, Figure

22. Press the knob in and hold while intermittently pressing and releasing the piezo ignition device to create the spark ignition.

WARNING

Explosion Hazard

If pilot fails to light or goes out, wait 3 minutes before trying to relight pilot.

Dangerous gas mixtures can build up.

Failure to follow these instructions can result in death, injury or property damage.

S.I.T. Nova and Honeywell valves

Do not attempt to adjust step opening on these valves.

Check Gas Rate

1. After burner pressure adjustment, allow the heater to operate for at least 15 minutes and then re-check settings.

2. Remove the manometer and refit all covers to the valve.

3. Check gas flow rate at gas meter.

3. Once the pilot flame has lit, continue to hold in the control valve knob for an additional 20-30 seconds, then release. The pilot flame should remain on. If the pilot fails to light, or goes out, wait 3 minutes before trying to light the pilot again.

4. Once the pilot flame has been established it will remain on constantly unless the gas or electricity supplies are interrupted or the limit thermostats operate.

Page 49

SECTION 11: COMMISSIONING THE HEATER

To Operate the Main Burner

Replace the electrical plug onto the gas valve. Press in slightly and turn the valve control knob a quarter turn counter-clockwise to the "flame" symbol. With the external controls in an on position and calling for heat the main burner will now fire.

Carry out the checks of burner settings as described on Page 42, Section 11.4.2.1.

11.6 Commissioning Tests - (all models) Spillage Tes t

With the main burner operating for at least 15 minutes carry out a spillage test on the draught diverter in accordance with local codes. Ensure that all doors and windows in the area are closed and that any extract fans are turned ON.

If spillage is occurring then corrective action MUST be taken. See Page 3, Section 3 and Page 14, Section 6 for design of flues and Page 17, Section 7 for air supply.

switch (if fitted) and room thermostat to the users’ requirements.

11.11 Complete the Installation

Ensure that all covers are fitted correctly and all test points are properly sealed.

11.12 Instruction to the User

Explain the controls of the heater to the user including how to turn it on and off, using the controls fitted on site. Give this manual to the user. Ensure that the user is shown and understands the user instructions on Page 44, Section 12 through Page 47, Section 12.9 and all warnings defined in this manual.

Do not use electrical Isolator for control of heater. Electrical Isolator will switch off the fan. Heat exchanger will be damaged. Warranty will not cover damage to the heat exchanger if operated improperly.

11.7 Combustion Testing - (all models)

The only adjustment to alter combustion performance is burner pressure, combustion quality must be tested to prove correct heater operation. Incorrect results will indicate faults with the installation or appliance.

Combustion testing must be carried out with all covers in place. The flue gas is sampled in the flue, within 1 metre of the heater. The values of CO

(Carbon Dioxide) should be between 5.5% and

6.5%. CO (Carbon Monoxide) should be no more than 0.005% (50 PPM). Temperature rise of the flue gases above ambient should be approximately 160°C to 180°C.

11.8 Pilot Drop-Out Test - Manual Ignition Models

Carry out the Pilot Drop-Out Test as described on Page 49, Section 13.5 and ensure a positive result.

11.9 Turning Off the Heater - (all models)

Set the external controls to the off position and the main burner will stop. The fans will run until they are stopped automatically by the fan thermostat. Do not use the electrical isolator for shutting off the burner. This will switch off the fan prematurely and may damage the heat exchanger.

11.10 External Controls

External Controls may include time switch, room thermostat and manual switch.Operate each control to ensure that they function correctly. Set the time

Page 50

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

SECTION 12: USER INSTRUCTIONS

12.1 User Instructions

Figure 20: Heater Operating Sequence

Automatic Ignition

The CUHA/A, CUHB/A, CUHC/A & CUHD/A ranges of heaters are fully automatic and operate from the external controls fitted on site. The only user controls at the heater are the: Burner lockout

THERMOSTAT

CALL FOR

HEAT

BURNER

RUN

reset button................See Page 45, Section 12.4.1

Fan run button ........... See Page 44, Section 12.3.1

FAN

Limit thermostat

reset .......................... See Page 44, Section 12.3.1

Second limit thermostat

reset button ...............See Page 45, Section 12.3.2

(Models 340B/C & 380B/C have two second limit

NOTE: On some fully ducted heaters the fan will come on during the burner firing cycle and not wait for the temperature rise.

thermostat reset buttons.)

2-3 MINUTES

CLOSE DOWN

RUN ON

Manual Ignition

The CUHA, CUHB, CUHC & CUHD ranges of heaters are manual ignition of the pilot, but operate automatically from the remote controls fitted on site. The user controls on these heaters are: Main gas valve controls for lighting the pilot and

main burner ................See Page 45, Section 12.7.1

..................................... and See Page 46, Figure 22

Fan run button ............ See Page 44, Section 12.3.1

Limit thermostat

reset............................See Page 44, Section 12.3.1

Second limit thermostat

reset button................. See Page 45, Section 12.3.2

12.2 Heater Operation

When the heater has been switched on by the remote controls installed on site the main burner will automatically turn on.

12.3 Common User Controls (all models)

12.3.1 Combination Fan/Limit Thermostat

The Combination Fan/Limit Thermostat is located on the top right hand side of the heater. See Page 7, Section 4.2. This control ensures the heater does not blow cold air in the normal heating cycle and protects the heat exchanger against overheating.

Figure 21: Fan/Limit Thermostat

If the air flow is reduced due to power failure the limit thermostat will cause the burner to lockout.

Red limit Reset Button

(Press to reset)

White fan button

Pull out for normal operation.

Press in for constant fan.

For automatic ignition heaters, the burner control box will control the safe ignition of the pilot and main flame.

For manual ignition, the pilot flame must be manually ignited and constantly lit so that the external controls may operate the main burner.

All heaters require a constant gas and electricity supply which must not be interrupted during the normal operation of this heater.

The combination fan/limit thermostat is preset during commissioning.

See Page 38, Section 11.3

NOTE: To reset the heat exchanger must be cool.

Page 51

12.3.2 Secondary Limit Thermostat

Press to reset

Screw on cover

There are two of these thermostats on Models 340B/C and 380B/C which are sited on the rear panel below the fans. These are hand reset devices to give further protection against fan failure.

NOTE: To reset the heat exchanger must be cool.

12.4 Automatic Ignition User Controls

WARNING

SECTION 12: USER INSTRUCTIONS

2. The automatic firing sequence will begin as described on Page 56, Figure 26. The heater will now operate automatically under the control of the on site controls. Following long shut down periods, the control may go to lockout. See Page 45, Section 12.4.1.

12.5.2 To Turn the Heater Off

Set the installed remote controls to the “OFF” position. The burner will turn off immediately. The fan will continue to run for a few minutes. To restart turn the control used above to “ON”.

12.6 Manual Ignition User Controls

12.6.1 Multifunctional Gas Valve

The gas valve fitted to all manual ignition unit heaters is shown on Page 46, Figure 22. The gas valve is used to control the gas supply while lighting the pilot flame by hand. Follow the instructionson Page 45, Section 12.7 to light the pilot and operate the main burner.

Explosion Hazard

If control locks out, do not make more than 3 attempts to restart the heater.

Dangerous gas mixtures can build up.

The fault must be traced and repaired by a registered installer or service engineer.

Failure to follow these instructions can result in death, injury or property damage.

12.4.1 Burner Lockout Reset Button

The red warning light will illuminate when the control has gone to lockout. This may be caused by flame failure. After lockout wait three minutes before attempting to reset the control. Press the reset button on the side of the heater near the warning lights, or the remote reset if fitted.

12.5 Automatic Ignition Lighting Instructions

For types CUHA/A, CUHB/A, CUHC/A and CUHD/A only. (See Page 45, Section 12.7 for lighting manual ignition heaters.)

12.5.1 To Turn On Heater

1. Ensure that the electrical and gas supplies to the heater are on. Check that the on site controls are “ON”.

NOTE: The thermostat must be above the ambient temperature for the heater to operate.

12.7 Manual Ignition Lighting Instructions

For types CUHA, CUHB,CUHC and CUHD only. (See Page 45, Section 12.5 for lighting automatic ignition heaters.)

12.7.1

Ensure that the electrical and gas supplies to the heater are on. Check that the remote controls are set to “OFF”.

WARNING

Explosion Hazard

If pilot fails to light or goes out, wait 3 minutes before trying to relight pilot.

Dangerous gas mixtures can build up.

Failure to follow these instructions can result in death, injury or property damage.

To Light Pilot (See Page 46, Figure 22.)

1. Press in the manual control knob of the gas valve and turn counter-clockwise to the star symbol.

2. Press the knob fully in and hold while pressing and releasing the piezo ignition device to create the spark ignition.

Page 52

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

3. Once the pilot flame has been lit (visible through the rear panel near the gas pipe to the burner) continue to hold in the control valve knob for 30 seconds, and then release. The pilot flame should now remain on.

4. Once the pilot flame has been established it will remain on providing that the gas or electricity supplies are not interrupted and the limit thermostats do not operate.

To Operate The Main Burner

Press in slightly and turn the valve control knob a quarter turn counter-clockwise to the "flame" symbol. Set the external controls to the "ON" position. The thermostat must be above the ambient temperature for the heater to operate. The main burner will now operate automatically providing that the pilot flame remains alight.

Step 12.7.2 To Turn the Heater Off

Set the external controls to the “OFF” position. The burner will turn off immediately The fan will continue to run for a few minutes. The heater will remain off until the controls are turned on again.

12.8 Simple Fault Finding (all models)

Some possible reasons for the heater not operating are:

1. Gas supply not turned ON.

2. Electricity supply not turned ON.

3. The time and/or temperature controls are not “ON”.

4. One or both of the Limit Thermostats may have operated. This may be caused by an interruption of the electrical supply or failure of the distribution fan.

If the Limit Thermostats persistently operate, there is a fault which must be investigated by a contractor qualified in the installation and service of gas-fired heating equipment.

12.8.1 Simple Fault Finding Automatic Ignition Heaters

If the burner fails to ignite for any reason, it will go to lockout. This will be indicated by the red light on the heater or at the remote indicator (if fitted).

1. Wait one minute to reset. Press in and release the lockout reset button. If a remote reset is not fitted access this button through the hole in the electric box cover near the indicator lights.

Lockout should not occur during normal operation of the heater and indicates there is a fault condition which must be corrected.

Figure 22: S.I.T. Nova Valve for Manual Ignition, Operation

Piezo Ignition Device

Press in and turn to start

OFF Position START Position

Press in and hold to light pilot

Press in and turn to run burner

Press in and

turn to stop

Press in and

turn to stop

BURNER RUN Position

Page 53

SECTION 12: USER INSTRUCTIONS

12.8.2 Simple Fault Finding Manual Ignition Heaters

1. Ensure that the pilot flame is lit. See Page 45, Section 12.7.

2. Ensure that the control knob of the gas valve is turned to the main flame position.

3. If the pilot flame fails regularly, ensure that the electrical supply to the heater is not being interrupted. Electrical interruption for even a few seconds will cause the interrupter relay to turn off the pilot.

12.9 Service Requirements

This heater will require servicing annually. When operating the heater in a dirty or dusty area, more frequent service may be necessary. The service must be done by a registered installer/ contractor qualified in the installation and service of gas-fired heating equipment or your gas supplier in accordance with the requirements of this manual.

For service, contact your Heating Supplier.

The heater cabinet may be cleaned using a damp cloth and domestic detergent. Do not use excessive water or abrasives.

FOR YOUR SAFETY

If you smell gas:

1. Open windows.

2. DO NOT try to light any appliance.

3. 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.

7. If you cannot reach your gas supplier, call the Fire Department.

WARNING

Fire Hazard

Do not store or use petrol or other flammable vapours and liquids in the vicinity of this or any other appliance.

Failure to follow these instructions can result in death, injury or property damage.

Page 54

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

SECTION 13: SERVICING

13.1 Servicing Instructions

After commissioning, the heater will require maintenance to be carried out annually. If the heater is used in a dirty or dusty area, more frequent maintenance may be necessary.

Installation, Service and Annual Inspection of heater must be done by a contractor qualified in the installation and service of gas-fired heating equipment.

3. Check that the pilot gas pipe (where fitted) is clear of any deposits and that there are no cracks or gas leaks. Any cracks in the pipes or pipe joints must be repaired. See Page 62, Section 16.3.

4. Clean any deposits from the main burner which may have formed in the injectors or venturi of the burner. See Page 60, Section 16.2.

5. Check the condition of the thermal insulation at the bottom of the burner compartment and replace if necessary. The foil face of this insulation must be complete and unbroken.

WARNING

13.2 Fan/Motor Assembly Maintenance (all models)

The main fan bearings are permanently sealed and do not need lubrication. Before cleaning, turn off gas and electrical supply.

Cut Hazard

Turn off gas and electrical supply before maintenance.

Fan can start automatically at any time.

Failure to follow these instructions can result in severe injury or product damage.

NOTE 1: After any maintenance or repair work always test fire the heater in accordance with the commissioning instructions on Page 38, Section 11 through Page 43, Section 11.12 to ensure all safety systems are in working order before leaving the heater to operate. Minor faults may be traced by using the troubleshooting charts on Page 53, Section 15 through Page 59, Section 15.6.

NOTE 2: Check all gas pipes and pipe joints to ensure there are no cracks or gas leaks. Any cracks in the pipes or pipe joints must be repaired.

13.1.1 Burner Maintenance

Burner maintenance is similar for manual and automatic ignition heaters. Where there is a significant difference, the two types are referred to separately:

1. Remove the Burner Assembly.

See Page 60, Section 16.1 through Page 62, Section 16.3.

2. Check condition of the pilot burner (where fitted), ignition electrode and flame probe (for automatic), or thermocouple (for manual) as appropriate. Clean off any deposits which may have been formed on the thermocouple or flame probe. Replace as necessary.

with a small flue brush and a vacuum cleaner after removing the burner tray. 48

Remove the fan guards and use a small brush or duster to clean the fan blades from each side of the fan(s). Replace fan guards when done.

13.2.1 For CUHB & CUHC Centrifugal Fan Models

CUHB and CUHC models are fitted with thermally protected three speed fans. The General Technical Data Table (See Page 8, Section 4.3) indicates the number of fans and the standard running speed for each model. For CUHC models, the fans may be accessed via the removable panels in the top, bottom and sides of the inlet spigot compartment as required.

Do not operate at higher speeds than the original setting on the heater without prior consultation with Roberts-Gordon. The "HIGH" speed option is available to give the normal required air flow against higher static pressures and is not intended to be operated free blowing or against low resistance. Use of the fans under these conditions may cause the fan thermal overload to operate and the fan thermostat to cycle.

Where two or three fans are fitted they must all be operated at the same speed. They will be switched using a fan contactor built into the heater. See Page 64, Section 16.6.2.

13.3 Heat Exchanger Maintenance

The heat exchanger will remain clean unless a problem has developed with combustion. Inspect the heat exchanger. Look for signs of overheating at the lower edges which may indicate burner over firing or persistently low air flows. Any deposits in the heat exchanger may be removed

Page 55

13.4 Gas Control Valve Maintenance (all models)

No regular maintenance is required on these devices. To change gas control valves, See Page 60, Step 16.1.2 and Page 63, Section 16.4.

Do not repair or disassemble on site. Replace faulty gas valves with genuine ROBERTS GORDON

replacement parts.

13.5 Manual Ignition Pilot Drop Out Test

To check that the flame failure device operates correctly:

1. With the pilot flame lit continuously for at least ten minutes, turn off the gas isolating valve and watch the pilot flame.

2. Measure the time taken from the pilot flame going out until the gas safety valve operates, which can be felt and heard as a dull click. The time must be less than 60 seconds.

SECTION 13: SERVICING

If the test fails and more than 60 seconds elapse before the safety valve operates, the thermocouple must be replaced. Use only genuine ROBERTS GORDON

replacement

parts, See Page 62, Section 16.3.

Repeat the test to confirm a positive result.

Page 56

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

SECTION 14: CONVERSION BETWEEN GASES

14.1 General NOTE: All CUH 60 models can only be operated on

10, Section 4.5, Technical Data Tables for part numbers and specification numbers.

Natural Gas. Do not operate these models on L.P.G. All versions of the heaters use the same main burner bars and pilot burners.

14.3.1 Tandem Range Valves

Tandem range main gas valves cannot be converted between gasses as they are constructed either with

Natural Gas

All natural gas versions use the same main burner injectors, marked 840, and pilot injectors (where fitted) marked 34. The gas valves vary according to

or without a governor. These valves must be changed for the correct type as listed in the data tables on Page 8, Section 4.3 through Page 10, Section 4.5.

the models size and method of control. In all cases the valve contains a gas pressure regulator to allow for setting of the burner pressure.

L.P.G.

All L.P.G. versions use the same main burner injector, marked 250, and pilot injectors (where fitted) marked 19. The gas valves vary according to the models size and method of control. If the gas valve contains a gas pressure regulator, it is disabled. The correct operation of the heater depends on the close control of the gas inlet pressure to the appliance.

14.3.2 Nova Range Valves

Nova range main valves may be converted to operate with or without a burner gas pressure regulator.

To Convert Nova valve from Natural Gas to L.P.G. (See Page 51, Figure 24).

1. Remove the dustcap of the pressure regulator.

2. Completely unscrew the governor spring assembly and remove it complete with its spring.

3. Replace the governor spring assembly and dustcap with the exclusion screw.

14.2 Burner Conversion

To convert the burner assembly from one gas to the other is the same for all types of heater.

1. Remove the burner tray as on Page 60, Section

4. Tighten the exclusion screw into the body of the regulator until it stops. The regulator is now disabled. The step opening feature of the main valve will still operate.

16 and remove all of the main burner injectors.

2. Replace with the injectors for the new gas.

3. Remove the pilot burner assembly where fitted, keeping the flame monitor, and spark electrode.

4. Fit the new pilot burner injector following the instructions on Page 62, Section 16.3.4.

To Convert Nova Valve from L.P.G. to Natural Gas

1. Remove the dustcap of the pressure regulator.

2. Completely unscrew the exclusion screw and remove it.

3. Replace the exclusion screw with the governor spring assembly. Adjust for appropriate burner

14.3 Gas Valves - Automatic Ignition

There are three types of valves used for this range

pressure. See Page 10, Section 4.5.

4. Screw in dustcap.

of heaters. See Page 9, Section 4.4 through Page

Figure 23: Pilot Burner Options

Manual Ignition

Thermocouple tip

Electrode

Description Part Number S.I.T. Part Numbers

Pilot Bracket B186 0.140.020 Pilot Burner Injector L.P.G. Marked 19 B088 0.977.148 Pilot Burner Injector Nat. Gas Marked 34 B184 0.977.103

Automatic Ignition Models 340 & 380

Flame Probe

ElectrodeInjector Injector

Page 57

Figure 24: Conversion of Nova Family Valve

SECTION 14: CONVERSION BETWEEN GASES

The valve shown is the Nova manual ignition version, conversion of the automatic ignition version is exactly the same.

Description Part Number

Exclusion Screw L425 Governor Spring Assembly L436 Dustcap L437

14.3.3 Conversion of Honeywell Valve to L.P.G.

1. Remove the dustcap of the pressure regulator.

2. Screw the regulator adjusting screw clockwise down fully.

3. Replace the dust cover tightly and apply paint or similar across the mating face of cover and valve.

The regulator is now out of action and the heater must be supplied with a gas pressure closely controlled at 37 mbar for Propane or 29 mbar for Butane.

Dustcap

Exclusion screw

for L.P.G.

Governor spring

assembly for

natural gas.

0 2 2

EV2

14.3.4 Conversion of Honeywell Valve from L.P.G. to Natural Gas

1. Remove the dustcap of the pressure regulator.

2. Unscrew the regulator adjusting screw counter clockwise to a halfway position before lighting the appliance and further adjusting this screw to give the appropriate burner pressure shown in the table on Page 10, Section 4.5.

3. Replace the dustcap.

Figure 25: Conversion of Honeywell Gas Valve for L.P.G.

Inlet flange with inlet

pressure test point

Electrical

Connection

Pressure regulator under screw cover

Outlet pressure test point

Outlet flange

Page 58

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

14.4 Conversion of Manual Ignition Valves

All CUH range manual ignition unit heaters use an S.I.T Nova multifunctional gas valve.

Nova Range Valves

Nova range main valves may be converted to operate with or without a burner gas pressure regulator.

To convert Nova valve from Natural Gas to L.P.G. (See Page 51, Figure 24).

1. Remove the cover of the pressure regulator.

2. Completely unscrew the regulator adjusting screw and remove it complete with its spring.

3. Replace the adjusting screw and original cover with the exclusion screw.

This device screws fully into the body of the regulator until it stops and puts the regulator out of action. The step opening feature of the main valve will still operate.

To Convert Nova Valve from L.P.G. to Natural Gas

1. Remove the cover of the pressure regulator.

2. Completely unscrew the exclusion screw and remove it.

3. Replace the exclusion screw with the regulator adjusting screw complete with its spring. Adjust for appropriate burner pressure. See Page 9, Section 4.4.

Page 59

SECTION 15: TROUBLESHOOTING

15.1 General for Automatic Ignition

Service and repair must be performed by registered installers or registered service engineers.

Failure to follow these instructions can result in death, injury or property damage.

Start

SECTION 15: TROUBLESHOOTING

WARNING

Explosion Hazard

Are gas & electrical

supplies on?

Ye s

Is Red lockout

warning light on?

Does the fan run?

Ye s

With external controls on, does the burner continue

through the heating cycle?

Yes

Turn on supplies.

Use 15.2 to test burner.

Press the white button on the

combination thermostat.

Does the fan run now?

Yes

See section 11.3 to

check fan thermostat settings.

Has burner Locked Out?

Use 15.5 to test fan.

Replace combination

thermostat.

Is Combination thermostat

set correctly?

See Section 11.3.

Adjust or replace

as necessary.

Yes

Use 15.2 to test burner.

Yes

Heater Operating

TROUBLESHOOT ENDS.

If problems persist, contact

ROBERTS GORDON

Tel: +44 (0)1902 498733

www.combat.co.uk or www.rg-inc.com

For your safety and optimum heater performance use only ROBERTS GORDON® replacement parts.

Conduct Commissioning procedure as on Page 38, Section 11

Page 60

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

15.1.1 General - Manual Ignition

WARNING

Explosion Hazard

Service and repair must be performed by registered installers or registered service engineers.

Failure to follow these instructions can result in death, injury or property damage.

Start

Are gas & electrical

supplies on?

Yes

Does pilot flame light when

gas valve button is pressed

and piezo igniter is

repeatedly pressed?

Yes

Does pilot remain on when

gas valve start knob is

released?

Ye s

Does main burner

come on?

Yes

Turn on supplies.

Does pilot ignite from

a lighted taper?

Is ignition circuit sound?

Check piezo igniter, lead

and electrode. Repair or

replace as necessary.

Use 15.3.2 to trace fault.

Is gas valve knob in burner

position? Are external

controls on, for

heat demand?

Yes

Check gas and

electrical supplies.

Does fan run?

Yes

With external controls on,

does the burner continue

through the heating cycle?

Yes

Heater Operating

TROUBLESHOOT ENDS.

Use 15.5 to trace fault.

Is Combination thermostat

set correctly?

See Section 11.3.

If problems persist, contact

ROBERTS GORDON Tel: +44 (0) 1902 498733

www.combat.co.uk or www.rg-inc.com

Adjust or replace

as necessary.

For your safety and optimum heater performance use only ROBERTS GORDON® replacement parts.

Conduct Commissioning procedure as on Page 38, Section 11

Page 61

15.2 Troubleshooting For Automatic Ignition Burner Systems

There are two possible burner controls used. Satronic DKG972 or Honeywell S4563. They both have similar operating sequences. Honewell has a built in ignition device. To measure flame current, connect a 0 - 50 µA DC meter in series with the flame probe by using the flame probe jack plug or connection at control box for Honeywell control. If the meter reads Negative values, then reverse the test leads. See Page 56, Section 15.2.1 for DKG 972 Control Box Data.

Start

Do not touch ignition components.

SECTION 15: TROUBLESHOOTING

WARNING

Electrical Shock Hazard

Are gas & electrical

supplies on?

Ye s

Is green light on?

Yes

Is Red lockout warning

light on?

Is the ignition

spark operating?

Yes

Is the pilot flame (or main

flame for direct flame

ignition) igniting?

Yes

Are external controls on?

Press in reset button on

control box near warning

lights or remote reset

button if fitted.

Is H.T. lead sound?

Is spark electrode sound?

Use Section 16.2.3 or 16.3

as appropriate.

Is the pilot gas

valve (or main gas valve for

direct flame ignition) opening?

Yes

Voltage from ignition components is high.

Failure to follow these instructions can result in death or electrical shock.

Have limit thermostats

operated or light faulty?

Reset or Replace as

necessary.

Spark generator faulty.

Replace generator

(or control if Honeywell).

Ensure gas supply is on

and purged of air?

Yes

Is Red lockout warning

light on?

Does the main burner

operate?

(omit for direct flame ignition)

Yes

Heater Operating

TROUBLESHOOT ENDS.

Use 15.4 to test

gas valves.

Is valve working now?

Yes

Is flame current at

least 1 m Amp DC

when the flame ignites?

Is there 230v from

terminal 5 of control box,

Satronic, or main gas valve

output on Honeywell Control.

Use Section 15.4 to

check gas valves.

If problems persist, contact

ROBERTS GORDON Tel: +44 (0) 1902 498733

www.combat.co.uk

or www.rg-inc.com

Yes

Use Section 15.3.1 to test flame supervision system.

Ensure flame probe and

Is inlet gas pressure

correct for gas type.

Control box faulty.

Replace with correct type.

pilot burner (if fitted) are sound.

Yes

Use Section 16.2.3 or

16.3 as appropriate.

For your safety and optimum heater performance use only ROBERTS GORDON

replacement parts.

Conduct Commissioning procedure as on Page 38, Section 11

Page 62

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

15.2.1 Satronic DKG 972 Control Information System

The Satronic DKG 972 control is a micro-processor control which provides information about the current operation of the burner and the cause of any faults. The information is available by reading the “flash code” at the red LED within the lockout reset button as detailed below.

FLASH CODE KEY

❘ = short pulse ❚ = long pulse

. = short pause _ = long pause

15.2.2 Program Sequence Display

Messages for normal operation

MESSAGE

Waiting time (tw)

Pre-ignition (tvz)

Safety time (ts) & post ignition (tn)

Delay 2nd stage (tv2)

Running

FLASH CODE

❘ ❘ ❘ .

❘ ❘ ❘ ❘ .

❚ ❘ .

❚ ❘ ❘ .

❘ _

These indications will repeat as long as the lockout reset button is not reset.

15.2.3 Fault Display Messages

On burner failure the red LED is illuminated for a period of approximately 10 seconds, followed by a brief “dark phase”, then one of the following flash codes will indicate the cause of the fault. This indication will repeat as long as the lockout reset button is not reset.

Lockout within lockout safety time. No flame establishment. ❘ ❚ ❚ ❚ ❚

Lockout during normal burner operation Gas supply or detector failure. ❘ ❘ ❚ ❚ ❚

Lockout caused by manually pressing the reset button. ❘ ❘ ❚ ❚ ❚ _ ❚ ❚ ❚ ❚ ❚

15.2.4 Additional Monitoring Equipment

By the use of additional monitoring equipment, a short history of recorded faults is also available. There are two types of additional monitoring devices available from Satronic Ltd. The “satropen” is a small pocket reader designed to give a visual read out of status, flame current and supply voltage. Computer software is available to allow access to the current information, fault information and stored data.

Figure 26: Automatic Burner Control Box Sequence

Burner sequence for Honeywell S4563 or Staronic DKG 972 controls

Supply 230v

Ignition Spark

Start Gas Valve

Main for direct main flame ignition

Flame Signal

Main Gas Valve

Honeywell Control

Satronic Control

Tv2

N/A

3.0 Seconds

Tv2

Required Incoming Signals

Signals Output By Control

CLOSE DOWNRUNSTART

Pilot IgnitionDirect Main Flame Ignition

10 Seconds40 Seconds

10 Seconds3.5 Seconds

25 Seconds

S 4563 BS 4563 CType

10 Seconds10 Seconds

10 Seconds

25 SecondsN/A

DKG 972 Mod 10DKG 972 Mod 3Type

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.

Page 63

15.3 Flame Supervision System

15.3.1 Automatic Ignition Systems

Maximum flame current

with no flame.

SECTION 15: TROUBLESHOOTING

MInimum flame current

with pilot only.

START

Connect a DC ammeter in

series with the flame probe.

Is the green light on?

Yes

Is there a current flowing in

the flame probe circuit with no

flame present?

Does lockout occur when

there is a flame present?

Use section 15.2 to

Yes

trace the fault.

Is the connecting lead damaged? Is the flame probe damaged or touching earthed

components?

Is inlet burner gas pressure

correct? Is live and neutral

polarity correct? Is

flame probe circuit correct?

Repair or replace as

necessary.

0 to 0.5 mA DC.

1.0 mA DC.

Typical flame current 3.0 to 5.0 mA

with main Burner on.

To measure flame current, connect a 0 - 50 µA DC meter in series with the flame probe by using the flame probe jack plug. If the meter reads negative values, then reverse the test leads. For DKG Controls this information is available by using a special reader unit “satropen”. See Page 56, Section 15.2.4.

Repair or replace as

Yes

necessary.

Control box faulty.

Replace with correct type.

Heater Operating

TROUBLESHOOT ENDS.

If problems persist, contact

ROBERTS GORDON Tel: +44 (0) 1902 498733

www.combat.co.uk or www.rg-inc.com

15.3.2 Flame Supervision Systems - Manual Ignition

START

Does pilot flame light when gas valve button is pressed

and piezo igniter is

repeatedly pressed?

Yes

Does pilot flame stay on

gas valve start knob

is released?

Yes

Does main burner

operate?

Yes

Heater Operating

TROUBLESHOOT ENDS.

Is gas supply correct?

Fault elsewhere.

Correct gas supply.

Wait 3 minutes. Try again.

Gas valve knob must be fully

depressed in start position

and held for at least 20 seconds

after pilot flame has lit.

Does pilot flame stay on?

Is gas valve knob in main

burner position? Are

external controls on?

If problems persist, contact

ROBERTS GORDON

Tel: +44 (0) 1902 498733

www.combat.co.uk or www.rg-inc.com

Does pilot ignite from

Yes

a lighted taper?

Use Section 16.3 to

inspect pilot assembly.

Is there 230v at the mains

connection for the thermocouple

interrupter relay and are

thermocouple interrupter leads

connected at the gas valve?

Yes

Is there 5 to 7 mv DC between

the thermocouple sheath and

the thermocouple interrupter

terminals of the valve?

Yes

Gas valve faulty.

Replace with correct type.

Is ignition circuit sound?

Check piezo igniter, lead

Yes

and electrode. Repair or

replace as necessary.

Have limit thermostats

Is there 5 to 7 mv on one

terminal only?

Thermocouple faulty.

Replace with correct type.

operated?

Interrupter relay faulty.

Yes

Replace with correct type.

For your safety and optimum heater performance use only ROBERTS GORDON® replacement parts.

Conduct Commissioning procedure as on Page 38, Section 11

Page 64

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

15.4 Troubleshooting for Solenoid Valves

NOTE: For manual ignition valves, the gas will not pass t

the main burner until the pilot accepted and the valve knob has been turned to main flame position.

START

Is 230v at the valve

terminals at the

appropriate time.

Yes

Is gas pressure at inlet of the

valve correct for gas type?

Note pressure found.

Yes

Fault elsewhere

flame has been lit and

Does gas pressure at outlet

of the valve rise when

valve turns on?

Ye s

Does gas pressure at

outlet of valve return to zero

when valve turns off?

Yes

Valve Operating

TROUBLESHOOT ENDS.

Valve faulty.

Replace with one of

correct type.

Valve faulty.

Replace with one of

correct type.

If problems persist, contact

ROBERTS GORDON Tel: +44 (0) 1902 498733

www.combat.co.uk

or www.rg-inc.com

15.5 Troubleshooting for Main Fan

For “B” and “C” versions with two or more fans, a contactor will be used to operate fans. See Page 59, Section 15.6 for contactor troubleshooting.

START

Does fan run

automatically?

Is power supply 230v at

terminals L to N of the

main terminal block?

Fault elsewhere.

Check wiring.

Yes

Is there 230v between

terminals 1 and N of the

main terminal block?

Yes

Fan motor or capacitor faulty.

Replace with correct type.

Combination thermostat faulty.

Replace with correct type.

Yes

Does fan turn on and

off while burner is firing

continously?

Fan Operating

TROUBLESHOOT ENDS.

Yes

Does fan run when white

button of combination

thermostat is pushed in?

Ye s

Use Section 11.3 to check

combination thermostat

settings. Reset or replace

as necessary.

If problems persist, contact

ROBERTS GORDON

Tel: +44 (0) 1902 498733

www.combat.co.uk or www.rg-inc.com

For your safety and optimum heater performance use only ROBERTS GORDON® replacement parts.

Conduct Commissioning procedure as on Page 38, Section 11

Page 65

15.6 Troubleshooting for Fan Contactor

START

SECTION 15: TROUBLESHOOTING

Does fan run

automatically?

Yes

Does fan turn on and

off while burner is firing

continously?

Fan Operating

TROUBLESHOOT ENDS.

If problems persist, contact

ROBERTS GORDON

Tel: +44 (0) 1902 498733

www.combat.co.uk

or www.rg-inc.com

Yes

Is power supply 230v at

terminals L to N of the

main terminal block?

Does fan run when white

button of combination

thermostat is pushed in?

Use Section 11.3 to check

combination thermostat

Yes

settings. Reset or replace

as necessary.

Yes

Ye s

NoNo

Fault elsewhere

Is there 230v between terminal 1 and N of the

main terminal block?

Yes

Is there 230v at the coil

terminals of the contactor?

Yes

Does contactor operate?

Yes

Is 230v available at both

the load input and output

terminals of the contactor.

Combination thermostat faulty.

Replace with correct type.

Wiring fault. Investigate.

Contactor faulty.

Replace with correct type.

Contactor faulty.

Replace with correct type.

For your safety and optimum heater performance use only ROBERTS GORDON® replacement parts.

Conduct Commissioning procedure as on Page 38, Section 11

Page 66

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

SECTION 16: REMOVAL AND REPLACEMENT PARTS

See warnings and notes on Page 48, Section 13 before removing or replacing parts.

16.1 Burner Tray

16.1.1 Lower panels

The burner tray may be removed complete with the gas valve train assembly or without. These instructions indicate how to remove the burner tray and valves separately.

NOTE: Burner tray has sharp edges.

To avoid injury, use care when handling these components.

Remove front and rear

lower panels.

Step 16.1.2 Gas Valve

Manual Ignition

Pilot Gas Pipe

Step 16.1.3 Remove Burner Tray

Thermocouple

Automatic Ignition

Unplug the flame probe lead from its socket and the HT lead from the electrode.

Pilot Valve assembly on models 340/380

16.2 Main Burner Bars / Injectors

16.2.1 Burner Bar Removal

Remove

Rear Baffle

Remove screws.

Remove

Retaining Bar

Page 67

16.2.2 Individual Bar and Injector Removal

16 mm

3 mm

SECTION 16: REMOVAL AND REPLACEMENT PARTS

On automatic ignition models 60 to 300 remove ignition electrode and flame probe first. Remove the individual bars by pulling up the front end out of its mounting slot and slide the burner off its injector. Start at this end.

Burner Bars

End burner with no cross lighter Remove last Install first

To remove unscrew the injectors

(13mm spanner).

Use

correct

injector.

See marking

and tables in

Section 4.

Use new

sealing washer

each time

Description Part Number

Main Burner Injector - Natural Gas B094 Main Burner Injector - LPG B095 Sealing Washer B210

Pilot position relative

to adjacent burner

Cross-section view of pilot

position relative to adjacent burner

16.2.3 Direct Main Flame Ignition for Automatic Ignition Up To Model 300.

Burner

Bars

To remove the Spark Ignitor and the Flame Probe remove the securing screw and slide them out of the holding bracket.

Main Burner

Manifold

Flame Probe

3 mm

Spark Igniter

Direct main flame

spark ignitor and

flame probe relative

to adjacent burner

Cross-section view of

direct main flame ignition

relative to adjacent burners

Page 68

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

16.3 Pilot Burner Assembly (where fitted).

Step 16.3.2 Pilot Bracket Assembly CAUTION: Do not kink or tightly bend the pilot gas pipe or thermocouple.

Main Burner Manifold

Natural gas and L.P.G. operate utilizing different pilot injectors. See Page 50, Figure 23.

The difference between manual and automatic ignition is:

• Manual Ignition heaters are controlled with a thermocouple.

Pilot Bracket Assembly

• Automatic ignition are controlled with a flame probe.

Burner Bars

The ignition electrode has a small tag connector for connecting the HT lead and ALWAYS fits into the centre hole of the pilot burner bracket. The thermocouple or (flame probe with permanently connected P.T.F.E. insulated wire) is fitted in the end hole of the pilot burner bracket.

16.3.1 Removal of Pilot Burner

Remove the rear lower panel of the heater and disconnect the pilot burner connections. See Page 60, Section 16.1.

Remove 2 set screws

Step 16.3.3

Push assembly forward so it will drop and pull clear of the main burner.

Step 16.3.4

Disconnect the thermocouple/flame probe, spark electrode and gas line from rear of the pilot burner bracket.

Fit correct injector onto the lip of the compression nut. Failure to comply will cause gas leaks and permanent damage.

Compression nut

Description Part Number

Pilot Burner Bracket B186 Spark Electrode J021 Automatic Ignition Flame Probe J035 Manual Ignition Thermocouple L432 Pilot injector Nat gas (marked 34) B184 Pilot injector LPG Gas (marked 19) B088

Pilot Burner Bracket

Pilot Burner Injector

Spark Electrode

Gas Line

Thermocouple/ Flame Probe

Page 69

SECTION 16: REMOVAL AND REPLACEMENT PARTS

16.4 Gas Control Valves

16.4.1 General

The gas control valves are easily accessible from the rear of the heater or may be withdrawn as part of the burner assembly. Remove the valves keeping the burner tray in place. The tables on Page 8, Section 4.3 through Page 10, Section 4.5 give details of the gas valve specified for use on the various heater models.

IT IS IMPORTANT THAT ONLY THE CORRECT GAS VALVES SPECIFIED FOR EACH MODEL TYPE ARE USED WHEN REPLACING THESE CONTROLS.

16.4.2 Removal of Gas Valves - All Models

See Page 60, Section 16.1.2 for gas valve removal. The pilot gas valves (where fitted) are supported on the inlet pipe fittings and the outlet is a 4 mm OD compression fitting. Electrical connection is by a three pin plug.

To remove gas valves

1. Turn off gas and electrical supply.

2. Where fitted, disconnect the pilot gas pipe at the compression fitting at the pilot gas valve and thermocouple at valve.

3. Disconnect the union between the gas supply pipe and the gas valve.

4. Disconnect the electrical plugs to all gas valves.

5. Disconnect the union or valve outlet flange between the gas valve and the burner.

Connect to the valve using the nut, screwed hand tight plus no more than ¼ turn with a spanner This is an electrical connection and must be clean, use NO compounds. See Page 62, Step 16.3.2 through Step 16.3.3.

16.4.4 Thermocouple Interrupter Relay

All manual ignition heaters are fitted with a thermocouple interrupter relay to interface between the limit thermostats and the thermocouple.

After replacement of limit thermostats or interrupter relay, perform commissioning checks to insure safe operation. See Page 38, Section 11.

Use only ROBERTS GORDON® replacement parts.

16.5 CUHA Axial Fan/Guard/Motor Assembly

The Axial fan unit for the CUHA range of heaters is supplied completely assembled and balanced. These components are not replaceable separately.

Step 16.5.1 Fan Removal and Replacement

Fan

Capacitor

Inside

Rubber

Washers

Metal

Washer

Disassemble gas train for automatic ignition

1. Where a separate pilot is fitted, separate the start and main gas valves.

2. Hold the main gas valve firmly in a vice and unscrew the pilot line from the main gas line at the ¼" elbow by ¼ turn.

3. Unscrew the pilot or the main gas valve from the main gas pipe.

To refit reverse the previous procedure.

• Use only a minimum amount of non hardening

gas seal so that excess sealant is not carried into the valve mechanisms.

• Ensure valves are assembled with the marked

gas flow in the correct direction.

• Ensure "O" ring seals are fitted to the inlet and

outlet flanges where appropriate.

• Commission valve as on Page 39, Section 11.4.

• See Page 50, Section 14 for converting between

natural gas and L.P.G.

16.4.3 Thermocouple

Be careful not to kink or crack the thermocouple tube.

Thermocouple

Interrupter Relay

Description Part Number

Axial Fan 35041- 101 A262A Axial Fan 39041- 101 A263A Axial Fan 42041- 101 A264A

16.5.2 To Replace the Fan Assembly

To replace the fan assembly reverse the procedure shown above. Fit rubber washers to the guard mountings to reduce vibration.

• Check that the fan blades are free to rotate before turning on the power to the fan.

• Strictly comply with the colour code of the fan wires to ensure correct operation. See Page 21, Section 10 wiring diagrams

• Replace the fan capacitor when changing a fan.

• Use only genuine ROBERTS GORDON

replacement parts.

Page 70

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

16.6 CUHB & CUHC Centrifugal Fan/Guard/Motor Assembly

The direct drive fan/s for the CUHB & CUHC range is supplied as a complete assembly. Take careful note of the electrical connections of the fan before disconnecting from the terminals.

For the CUHC versions fitted with an inlet spigot assembly, the fans may be accessed through the removable covers on the sides, top and bottom of the spigot, as required.

16.6.1 Fan Removal and Replacement

20 mm x 5 mm Adhesive Seal

is applied to the flange.

• Check that the fan blades are free to rotate without catching before turning on the power to the fan.

16.7 Combination Fan/Limit Thermostat

16.7.1 Removal and Replacement

1. Remove the cover retaining screw and pull off

the cover.

2. Disconnect the electrical connections by push-

ing in with a small screwdriver and pulling out the wires. See Page 12, Figure 5. The earth wire is held under a screw connection.

3. Unscrew two screws and withdraw the unit from

the cabinet feeding the cables through the plastic conduit connection.

4. To refit, reverse the above procedure re-using

the plastic conduit connection and reset as in the commissioning instructions on Page 38, Section 11 through Page 43, Section 11.12.

5. Remove link. See Page 12, Figure 5.

Permanent damage and a fire hazard will be caused by leaving this link in.

Description Part Number

Torin Fan DDC 270-270 A047 Torin Fan DDC 241-241 A049

Remove the fan by removing the fixing screws while supporting the weight of the fan (approx. 19 kg).

16.6.2 To Replace the Fan(s)

To reassemble reverse the procedure shown above.

• Fit new rubber seal between the fan flange and the heater rear panel.

• Fit to the rear panel in the correct orientation with the curved surface upwards.

• Strictly comply with the colour code of the fan wires to ensure correct operation. See Page 21, Section 10 Wiring diagrams.

• Use only genuine ROBERTS GORDON

replacement parts.

The three speed winding connections are: Low speed: White N, Red Live The other two windings are "parked" separately in spare terminals. Medium speed: White N, Blue live. The other two windings are "parked" separately in spare terminals. High speed: White N, Black live. The other two windings are "parked" separately in spare terminals.

WARNING

Fire Hazard

Break-off link must be removed from replacement thermostat.

Failure to follow these instructions can result in death, injury, property damage or product damage.

6. Seal limit setting by a suitable method (paint spot) to prevent unauthorized adjustment.

16.8 Second Limit Thermostat

16.8.1 Removal and Replacement

1. Remove the mounting nut securing the thermostat to the heater side.

2. Remove the heater lower rear panel to gain access to the body of the thermostat and its electrical connections.

3. Disconnect the push-on electrical connections from the thermostat.

NOTE: On Models 340 and 380 B & C versions the secondary limit thermostats are mounted on the fan mounting panel. The relevant fan will need to be removed to gain access to these thermostats.

Page 71

4. Remove the fan assembly from the heater rear.

See Page 63, Section 16.5.1 or See Page 64, Section 16.6

5. Carefully pull the capillary sensing probe through its access hole in the side of the heater heat exchanger being careful not to damage the capillary tube.

6. To refit a thermostat, first carefully straighten the capillary tube, it is important not to kink or crack it. Replace by reversing the above procedure

• Ensure that the sensing bulb is positioned against the base of the heat exchanger near the centre of the fan outlet. (Where there are two or three fans, the position of the sensing bulb should be towards the centre of the fan/s on the opposite side of the heater from the controls).

• Secure the capillary tube re-using the metal bracket.

SECTION 16: REMOVAL AND REPLACEMENT PARTS

Page 72

COMBAT® CUH UNIT HEATERS INSTALLATION OPERATION AND SERVICE MANUAL

16.9 Major Components Descriptions

Axial Fan 35041-101 P/N A262A

CUHA 60/100/200/240

Axial Fan 39041-101 P/N A263A

CUHA 120/140

Axial Fan 42041-101 P/N A264A

CUHA 160/180/280/300/340/380

S.I.T. Tandem (Natural Gas) 0.830.033 P/N L411

Automatic Ignition Gas Valve

S.I.T. Tandem (L.P.G. Gas) 0.830.020 P/N L413

Automatic Ignition Gas Valve

Centrifugal Fan DDC 270-270 P/N A047

CUHB/C 60/160/240/380

Centrifugal Fan DDC 241-241 P/N A049

CUHB/C 180/200

Honeywell VR 420AB 1002 Main Gas Valve P/N L059B

S.I.T. Nova (All Gasses) 0.822.117. Automatic Ignition Gas Valve P/N L421

0 2 2

0 4

2 V

S.I.T. Nova (All Gasses) 0.820.054.

Manual Ignition Gas Valve P/N L431

Page 73

Major Components Descriptions

S.I.T. Nova Exclusion Screw for L.P.G.

0.907.037 P/N L425

Pilot Burner Injector - Marked 34. P/N B184

(Natural Gas)

Pilot Burner Injector - Marked 19. P/N B088

(L.P.G. Gas)

SECTION 16: REMOVAL AND REPLACEMENT PARTS

Spark Electrode P/N J021

(all models with pilot burner)

Automatic Ignition Flame Probe P/N J035

S.I.T. 600mm Thermocouple P/N L432

Pilot Burner Bracket P/N B186

(all models)

Main Burner Injector - Marked 840. P/N B094

(Natural Gas)

Main Burner Injector - Marked 250. P/N B095

(L.P.G. Gas)

Sealing Washer P/N B210

for Main Burner Injector

Spark Igniter P/N J038

for Direct Main Flame Ignition

Honeywell Combination P/N K017A Fan/Limit Thermostat

Second Limit Thermostat P/N K120A

Flame Probe P/N J039

for Direct Main Flame Ignition

Thermocouple Interrupter Relay P/N L434

Page 74

Page 75

Page 76

Roberts Gorden CUHA, CUHC, CUHD, CUHA/A, CUHB/A Installation, Commissioning, Operation & Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual