Bradford White U2TW75T*RN, Руководство по обслуживанию

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U TT W SERVI C E PRO C EDURE I X
R esettable Thermal Switch Testing
and R eplacement
S t e p 1. R e mov e ou t e r j a ck e t doo r .
S t e p 2 . Di s conn e c t r e d wi r e l ea d s f r om r e s e tt a bl e t h e r m a l s wi t ch.
S t e p 3. U s ing a mul t im e t e r c a p a bl e of m ea s u r ing con t inui t y (Ohm s ),
pl a c e on e p r ob e of m e t e r on on e of t h e b r a ss conn e c t ion t a b s of
t h e r e s e tt a bl e t h e r m a l s wi t ch, a nd t h e r e m a ining p r ob e on t h e
o t h e r conn e c t ion t a b.
S t e p 4. If con t inui t y i s indic a t e d, t h e s wi t ch i s clo s e d, a llowing cu rr e n t t o p a ss .
S t e p 5. If con t inui t y i s no t indic a t e d, t h e s wi t ch i s op e n, po ss ibly du e t o a n ov e r h ea t ing condi t ion. T h e s wi t ch i s
d e s ign e d t o op e n a t p r e d e t e r min e d t e mp e r a t u r e s . An op e n s wi t ch c a n b e r e s e t by d e p r e ss ing t h e r e d colo r e d
bu tt on loc a t e d a t t h e c e n t e r of t h e s wi t ch. T h e ov e r h ea t ing condi t ion mu st b e d e t e r min e d p r io r t o pu tt ing t h e
w a t e r h ea t e r b a ck in s e r vic e .
Resettable Thermal S witch Continuity Testing
PRO BAB LE CA USE FOR RESETT AB LE THER MA L S W IT C H AC TIV A TION
PRO BAB LE CA USE C ORRE C TIVE AC TION
B urner F ailure
1. In s pe c t burner per SER V I C E P R OC E DU RE II
2 . Repla c e burner per SER V I C E P R OC E DU RE II
Wea k s wit c h or s wit c h
out of c alibration .
1. Repla c e re s ettable thermal s wit c h
Red Wire L ead s
P a g e 2 9
R
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