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UBX-UBZ-UDX-UDZ-IOM (07-23) 1034344-K
TABLE OF CONTENTS
GENERAL INFORMATION ................................................................... 3
References .............................................................................. 3
Important Safety Information................................................................. 4
Warranty ................................................................................ 4
Model Configuration ....................................................................... 4
Certification .............................................................................. 5
Installation Codes ......................................................................... 5
Heater Location........................................................................... 5
Heater Throw .......................................................................... 6
Mounting Height Requirements ............................................................ 7
Hazards of Chlorine ..................................................................... 7
Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Clearances ............................................................................. 10
Weights ................................................................................ 11
Combustion Air Requirements .............................................................. 11
INSTALLATION ........................................................................... 12
Unpacking and Inspection.................................................................. 12
Pre-Installation Checklist................................................................... 12
Heater Suspension ....................................................................... 13
Suspension of Heater Using Option CK8 or CK10 Hanger Kit.................................... 14
Suspension of Heater Using Option CK22 Hanger Kit .......................................... 15
Heater Suspension Using Field-Supplied Threaded Rods....................................... 15
Suspension of Heater with Downturn Nozzle ................................................. 15
Vent Connections ........................................................................ 15
Piping Connections ....................................................................... 15
Gas Supply Pressure ................................................................... 15
Gas Supply Piping ..................................................................... 16
Supply Piping Connections .............................................................. 16
Electrical Connections..................................................................... 17
CONTROLS .............................................................................. 19
Pressure Switch ......................................................................... 19
High Temperature Limit Control ............................................................. 21
Flame Rollout Switch (UDX and UDZ Model Unit Sizes 030–125) ................................... 21
Interlock Door Switch (UBZ and UDZ Models) .................................................. 21
Combination Gas Valve.................................................................... 21
Fan Motor .............................................................................. 21
Venter Motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Thermostat Options....................................................................... 22
Circuit Board (DSI Control Module)........................................................... 22
OPERATION ............................................................................. 23
Pre-Startup Checklist ..................................................................... 23
Startup................................................................................. 23
Operating Sequences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Vent System Testing ...................................................................... 27
Post-Startup Checklist..................................................................... 28
ADJUSTMENTS........................................................................... 28
Pressure Switch Replacement .............................................................. 28
Measure and Adjust Manifold (Outlet) Gas Pressure ............................................. 29
Measure and Adjust Manifold Gas Pressure—Elevation ≤2,000 Feet (≤610 Meters) .................. 29
Measure and Adjust Manifold Gas Pressure—Elevation >2,000 Feet (>610 Meters) .................. 31
