© 2014
Roberts-Gordon LLC
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TABLE OF CONTENTS
SECTION 1: Heater Safety......................................................1
1.1 Manpower Requirements .............................................1
1.2 Safety Labels and Their Placement..............................1
1.3 California Proposition 65 ..............................................1
SECTION 2: Installer Responsibility .....................................5
2.1 Wall Tag .......................................................................5
2.2 Corrosive Chemicals....................................................5
2.3 National Standards and Applicable Codes...................5
SECTION 3: Critical Considerations .....................................6
3.1 Basic Information.........................................................6
3.2 Manufactured Units......................................................6
3.3 Location and Suspension ............................................6
3.4 Minimum Required Installation Clearances .................6
3.5 Ventilation ....................................................................6
3.6 Gas Supply ..................................................................6
3.7 Electrical Supply ..........................................................6
3.8 Vent..............................................................................6
SECTION 4: Clearances to Combustibles.............................7
4.1 Required Clearances to Combustibles.........................7
4.2 Clearances to Combustibles ........................................7
SECTION 5: National Standards and Applicable Codes......8
5.1 Gas Codes...................................................................8
5.2 Aircraft Hangars ...........................................................8
5.3 Parking Structures and Repair Garages ......................8
5.4 Electrical ......................................................................8
5.5 Venting .........................................................................8
5.6 High Altitude.................................................................8
SECTION 6: Duct Heater Installation.....................................9
6.1 General ........................................................................9
6.2 Suspension................................................................ 10
SECTION 7: Venting .............................................................. 11
7.1 Venting........................................................................ 11
7.2 Vent Installation .......................................................... 11
7.3 Horizontal Venting....................................................... 12
7.4 Vertical Venting ........................................................... 12
7.5 Maximum Vent Lengths Table .................................... 12
7.6 Vent Material............................................................... 12
7.7 Replacing an Existing Heater in a Venting System..... 12
SECTION 8: Air Supply ......................................................... 17
8.1 Separated Combustion Installation ............................ 17
8.2 Building Ventilation..................................................... 17
8.3 Outside Combustion Air Supply ................................. 17
SECTION 9: Gas Piping ........................................................ 18
9.1 Connections............................................................... 18
SECTION 10: Wiring ..............................................................20
10.1 Positioning Thermostats...........................................20
10.2 Low Voltage Thermostat for Models
UHD[T][M][X][S][R] 150-400 ....................................20
10.3 UHD[X][S][R] Series Internal Wiring Diagram for
Single Stage Gas Valves .........................................21
10.4 UHD[X][S][R] Series Ladder Wiring Diagram for
Single Stage Gas Valves .........................................22
10.5 UHD[T][X][S][R] Series Internal Wiring Diagram for
Two Stage Gas Valves .............................................23
10.6 UHD[T][X][S][R] Series Ladder Wiring Diagram for
Two Stage Gas Valves............................................. 24
10.7 UHD[M][X][S][R] Series Internal Wiring Diagram for
Modulating Gas Valves............................................ 25
10.8 UHD[M][X][S][R] Series Ladder Wiring Diagram for
Modulating Gas Valves............................................ 26
10.9 Electrical Connection to the Heater......................... 27
SECTION 11: Operation and Maintenance ......................... 28
11.1 Pre-Start-Up Checks ................................................ 28
11.2 Begin Start-Up ......................................................... 28
11.3 Pressure Switch........................................................ 32
11.4 Turning Off the Heater .............................................. 32
11.5 External Controls...................................................... 32
11.6 Complete Start-Up ................................................... 32
11.7 Instruction to the User .............................................. 32
SECTION 12: User Instructions........................................... 33
12.1 Heater Operation..................................................... 33
12.2 Lighting Instructions ................................................ 33
12.3 Simple Troubleshooting ........................................... 33
SECTION 13: Servicing ........................................................ 35
13.1 Servicing Instructions .............................................. 35
13.2 Burner Maintenance................................................ 35
13.3 Heat Exchanger Maintenance ................................. 35
13.4 Gas Valve Maintenance........................................... 35
13.5 Flue Blower ............................................................. 35
13.6 Venting and Air Intake Pipe ..................................... 36
13.7 Maintenance Checklist ............................................ 36
SECTION 14: Troubleshooting............................................. 38
14.1 General.................................................................... 39
14.2 Troubleshooting For Automatic Ignition Burner
Systems................................................................... 40
14.3 Troubleshooting for Flame Supervision System....... 41
14.4 Troubleshooting for Gas Valves ............................... 42
14.5 Troubleshooting for Flue Blower .............................. 42
SECTION 15: Replacement Parts ........................................ 43
15.1 Gas Valve ................................................................ 43
15.2 Burner Compartment for Models UHD[T][M][X][S][R]
150-400 ................................................................... 44
15.3 Ignition Electrode and Flame Probe for Models
UHD[T][M][X][S][R] 150-400.................................... 46
15.4 Heat Exchanger....................................................... 47
15.5 Flue Blower for Models UHD[T][M][X][S][R]
150-300 .................................................................. 47
15.6 Flue Blower for Models UHD[T][M][X][S][R]
350-400................................................................... 48
15.7 Pressure Switch....................................................... 49
15.8 Ignition Control ........................................................ 49
15.9 Limit Switches ......................................................... 49
SECTION 16: Specifications................................................ 50
16.1 Dimension Data for Models UHD[T][M][X][S][R]
150-250.................................................................... 50
16.2 General Technical Data Table .................................. 51
16.3 Technical Data Table................................................ 51