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Ultra Low NOx Atmospheric Vent Water Heaters
with Direct Spark Ignition
Table of Contents
Introduction................................................................................................................... 3
How to Use This Manual .............................................................................................. 4
Tools Required for Service ........................................................................................... 4
Features ....................................................................................................................... 5
Specifications ............................................................................................................... 6
Sequence of Operation ................................................................................................ 9
Troubleshooting.......................................................................................................... 11
Service Procedure I: Thermostat Circuit Testing and Replacement .......................... 16
Service Procedure II: Combustion System Testing and Replacement ...................... 21
Service Procedure III: Burner Tube Inspection and Replacement ............................ 25
Service Procedure IV: Gas Valve Replacement ........................................................ 27
Service Procedure V: Blower Testing and Replacement .......................................... 28
Service Procedure VI: Flame Sensor Testing and Replacement .............................. 30
Service Procedure VII: Spark Rod Gap Adjustment and Replacement ..................... 32
Service Procedure VIII: Ignition Module/Control Board Replacement ....................... 34
Service Procedure IX: Blocked Vent Switch Inspection and Replacement ............... 35
Service Procedure X: Anode Inspection and Replacement ...................................... 36
Service Procedure XI: Display Module Replacement ................................................ 37
Service Procedure XII: Transformer Replacement .................................................... 38
Water Heater Installation Check list ........................................................................... 39
Water Heater Service Report ..................................................................................... 40
Parts List .................................................................................................................... 41
Glossary of Terms ...................................................................................................... 44
Notes .......................................................................................................................... 44
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