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Technical Training Department
©2003
Ashland City, Tennessee
SBN TANK TYPE COMMERCIAL GAS WATER HEATER
SERVICE HANDBOOK
SBN Service Handbook Introduction ................................................ 2-3
Installation Considerations ................................................................... 4
Clearances ....................................................................................... 4
Exterior Clearance ............................................................................ 5
Air Supply ......................................................................................... 6
Contaminated Air .............................................................................. 9
Flammable Items .............................................................................. 9
Gas Valve ....................................................................................... 10
Outlet View ..................................................................................... 11
Venting ........................................................................................... 12
Technical Data Venting .............................................................. 13-14
Sequence of Operation ........................................................................ 15
Top View ......................................................................................... 15
Front View ....................................................................................... 16
White Rogers Control ..................................................................... 17
HSI Board ....................................................................................... 18
Wiring Diagram ............................................................................... 20
Electrical Sequence ....................................................................... 21
Pre-Service Checklist........................................................................... 22
Control Board Diagnostic LED Interpretation and Troubleshooting
120 VAC Check to Heater ............................................................... 23
Polarity Check ................................................................................ 24
Continuity Check of High Limit ....................................................... 25
Upper Temperature Probe Check ................................................... 26
Inducer Check ................................................................................ 27
Blower Prover/Low Gas Pressure Circuit Check ............................ 28
HSI Voltage and Continuity Check ................................................. 29
Igniter and Gas Valve Circuit Check ............................................... 30
Gas Valve Coil Continuity Check .................................................... 31
Flame Prover Check ....................................................................... 32
Water Temperature Circuit Check ................................................... 33
TABLE OF CONTENTS
