SBN TANK TYPE COMMERCIAL GAS WATER HEATER
SERVICE HANDBOOK
ELECTRICAL SEQUENCE OF SBN WATER HEATER OPERATION
120VAC
Power to Heater Green LED - On
Call for Heat
Green LED - On
Module Self Check
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| Low Gas Pressure |
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| Switch is Closed |
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| Draft Proving Switch |
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| Is Open |
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| High Limit is Closed |
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| Inducer On |
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| Blower Prover |
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Closes |
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| Ignition Control Board – |
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| 120 VAC |
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Variable Voltage | HSI Warm Up |
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20 seconds |
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| Gas Valve Open |
| 3 Second Trial |
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| HSI - Off |
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| 3 Seconds to Prove |
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| Flame After HSI - Off |
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| Flame Proves |
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| Minimum Millivolt for | ||
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| 4.25 seconds | ||
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| Yes |
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| No | Yes | No |
Tank Heated to Set Temperature | 20 Second Blower Purge | Flash 7 Times | |||||
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| 2 More Trials |
| 1 Hour Auto Reset |
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| Gas Valve – Off |
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| To Prove Flame |
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Call for Heat LED - Off |
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60 Second Blower Post Purge | Yes |
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Blower Prover - Opens |
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| Flash 8 Times On Diagnostic LED | ||||
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Standby LED - On |
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| Lock Out for 1 Hour | ||||
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| Then Retry |
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©2003 | 24 | Technical Training Department |
Ashland City, Tennessee