Bradford White Combi2 TTW C-DW2-TW50T10FBN, Руководство пользователя

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Troubleshooting continued-
Control Sequence of Operation
Start up Sequence
Upon pow ering up, t he cont rol checks f or t he presence of t he vapor sensor, if t he
resist ance is in t he expect ed range t he cont rol w ill begin normal operat ion af t er 5 t o
8 seconds.
Normal Heating Sequence
1. The t hermost at senses a need f or heat .
2. The cont rol checks t he pressure sw it ch condit ion.
3. If t he pressure sw it ch is open, t he cont rol sends pow er t o t he blow er mot or.
4. The blow er st art s moving combust ion air t hrough t he combust ion syst em.
5. The pressure sw it ch closes.
6. The cont rol senses t he closed pressure sw it ch and st art s t he ignit ion process
by providing a spark at t he pilot elect rode and allow ing gas t o f low t o t he pilot .
7. When t he pilot is lit t he gas cont rol senses t he pilot f lame and opens t he main
gas valve.
8. The main burner is lit .
9. The main burner and blow er cont inue t o operat e unt il t he t hermost at is
sat isf ied.
10. When t he t hermost at is sat isf ied t he main and pilot gas valves close.
11. The blow er operat es f or a short post purge period bef ore shut t ing dow n.
12.
The w at er heat er remains in t he st and-by mode unt il t he next call f or heat .