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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 .....................................4
2.1 Wall Tag .......................................................................4
2.2 Corrosive Chemicals....................................................4
2.3 National Standards and Applicable Codes...................4
SECTION 3: Critical Considerations .....................................5
3.1 Basic Information .........................................................5
3.2 Manufactured Units......................................................5
3.3 Location and Suspension ............................................5
3.4 Minimum Required Installation Clearances .................5
3.5 Ventilation ....................................................................5
3.6 Gas Supply ..................................................................5
3.7 Electrical Supply ..........................................................5
3.8 Vent..............................................................................5
SECTION 4: Clearances TO combustibles ............................6
4.1 Required Clearances to Combustibles.........................6
4.2 Clearances to Combustibles ........................................6
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: Heater installation..............................................9
6.1 General ........................................................................9
6.2 Suspension..................................................................9
SECTION 7: Venting .............................................................. 10
7.1 Venting........................................................................ 10
7.2 Vent Installation .......................................................... 10
7.3 Horizontal Venting....................................................... 11
7.4 Vertical Venting ........................................................... 11
7.5 Maximum Vent Lengths Table..................................... 11
7.6 Vent Material............................................................... 11
7.7 Replacing an Existing Heater in a Venting System ..... 11
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 UHA[T][M][X][S]
150-400 .....................................................................21
10.3 UHA[X][S] Series Internal Wiring Diagram for Single
Stage Gas Valves ......................................................22
10.4 UHA[X][S] Series Ladder Wiring Diagram for Single
Stage Gas Valves ......................................................23
10.5 UHA[T][X][S] Series Internal Wiring Diagram for Two
Stage Gas Valves ......................................................24
10.6 UHA[T][X][S] Series Ladder Wiring Diagram for Two
Stage Gas Valves...................................................... 25
10.7 UHA[M][X][S] Series Internal Wiring Diagram for
Modulating Gas Valves ............................................. 26
10.8 UHA[M][X][S] Series Ladder Diagram for Modulating
Gas Valves ................................................................ 27
10.9 Electrical Connection to the Heater......................... 28
SECTION 11: Operation and Maintenance ......................... 29
11.1 Pre-Start-Up Checks ................................................ 29
11.2 Begin Start-Up ......................................................... 30
11.3 Pressure Switch........................................................ 34
11.4 Turning Off the Heater .............................................. 34
11.5 External Controls...................................................... 34
11.6 Complete the Start-Up ............................................. 34
11.7 Instruction to the User.............................................. 34
SECTION 12: User Instructions........................................... 35
12.1 Heater Operation..................................................... 35
12.2 Lighting Instructions ................................................ 35
12.3 Simple Troubleshooting ........................................... 35
SECTION 13: Servicing ........................................................ 37
13.1 Servicing Instructions.............................................. 37
13.2 Burner Maintenance................................................ 37
13.3 Fan/Motor Assembly Maintenance .......................... 37
13.4 Heat Exchanger Maintenance ................................. 38
13.5 Gas Valve Maintenance........................................... 38
13.6 Flue Blower ............................................................. 38
13.7 Venting and Air Intake Pipe ..................................... 38
13.8 Maintenance Checklist ............................................ 38
SECTION 14: Troubleshooting............................................. 41
14.1 General.................................................................... 42
14.2 Troubleshooting For Automatic Ignition Burner
Systems ................................................................ 43
14.3 Troubleshooting for Flame Supervision System....... 44
14.4 Troubleshooting for Gas Valves ............................... 45
14.5 Troubleshooting for Flue Blower .............................. 45
SECTION 15: Replacement Parts ........................................ 46
15.1 Gas Valve ................................................................ 46
15.2 Burner Compartment for Models
UHA[T][M][X][S] 150-400 ...................................... 47
15.3 Ignition Electrode and Flame Probe for Models
UHA[T][M][X][S] 150-400 ...................................... 49
15.4 Heat Exchanger....................................................... 50
15.5 Louvers and Louver Spring ..................................... 50
15.6 Flue Blower for Models UHA[T][M][X][S] 150-300 .. 51
15.7 Flue Blower for Models UHA[T][M][X][S] 350-400 .. 52
15.8 Pressure Switch....................................................... 53
15.9 Ignition Control ........................................................ 53
15.10 Axial Fan/Guard/Motor Assembly........................... 53
15.11 Limit Switches........................................................ 54
SECTION 16: Specifications ................................................ 55
16.1 Dimension Data for Models
UHA[T][M][X][S] 150-250 ...................................... 55
16.2 General Technical Data Table .................................. 56
16.3 Technical Data Table................................................ 56
