Component Specifications - A.O. Smith Water Heater 520 Direct Vent Indoor Service Manual

10. Component specifications

10-1. Burners.................................................................................................................... 18
10-2. Gas manifold........................................................................................................... 19
10-3. Fan motor................................................................................................................ 20
10-4. Fan motor for exhaust...........................................................................................
10-5. Gas valve assembly................................................................................................ 22
10-6. Flame rod................................................................................................................. 23
10-7. AFR rod....................................................................................................................
10-8. Heat exchanger....................................................................................................... 25
10-9. Secondary heat exchanger.................................................................................... 26
10-10. Flow sensor............................................................................................................. 27
10-11. Water control valve................................................................................................ 28
10-12. Thermistors............................................................................................................. 30
10-13. Exhaust thermistor................................................................................................. 31
10-14. Hi-limit switch....................................................................................................... 32
10-15. Hi-limit switch for exhaust.................................................................................... 33
10-16. Overheat cutoff fuse............................................................................................ 34
10-17. Freeze protection heaters..................................................................................... 35
10-18. Computer board..................................................................................................... 36
10-19. Transformer. ........................................................................................................... 37
10-20. Igniter....................................................................................................................... 38
10-21. Freeze protection thermostat..............................................................................
10-22. Surge box................................................................................................................
520 Indoor / 520 Outdoor Service Manual
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CONFIDENTIAL
Ver. 1.00
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