Bradford White UCG100H399, Руководство по обслуживанию

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1 2 0 vo l t pote n tia l e x posure .
Use cautio n maki ng vo l ta g e
checks to avoi d perso n a l i n jury .
WA R NIN G
Removi ng screw from
i n l et g as pressure tap wi ll
imme d iate l y a ll ow g as to
f l ow from pressure tap .
WA R NIN G
Ser vi ce Proce d ure II :
Combust i on System T est i ng an d Rep l acement
Observe burner operation through the sight g l ass l ocated on the combustion insert mounting f l ange . N orma l burner
operation shou l d ignite smooth l y, without evidence of coughing or huffing upon ignition . The burner f l ame shou l d be a b l ue
f l ame near the burner surface in a uniform f l ame pattern . Occasiona l ye ll ow or white streaks are norma l.
N ote: On th i s h i gh i nput mo d e l that uses meta l f i ber mesh burner a re d g l ow from the burner surface i s norma l.
N
Verify minimum gas supp l y piping requirements of : Minimum ¾” N PT
(Schedu l e 4 0 b l ack iron pipe recommended . )
Reconfigure gas supp l y piping
With manometer, check in l et gas
pressure . I s it stab l e between 7” &
1 4 ” W . C . static (heater not
running) ? (See i ll ustrations at right . )
I s gas supp l y pressure
regu l ator adjustab l e to
maintain proper and
stab l e setting ?
I nadequate l y
sized regu l ator .
Adjust gas
supp l y regu l ator .
Does in l et gas
pressure drop more
than 2” W . C . during
burner ignition ? ”
Can sparking be
seen/heard at the
spark rod to burner ?
Remove high vo l tage wire
connected at the spark rod and
ho l d approximate l y ¼” from
meta l ground with insu l ated
p l iers during the ignition cyc l e (3
second spark tria l period) . I s
there spark to ground ?
Check resistance of high
vo l tage cab l e . Resistance
shou l d be 0 - 1 Ohm . I f
resistance is high, rep l ace
spark cab l e . I f spark cab l e is
good, rep l ace contro l board .
Check continuity of
spark rod . I s
reading 0 - 1 Ohm ?
Rep l ace spark rod (see
“Spark Rod Gap I nspection
and Rep l acement”) .
Does main burner l ight ?
Check spark gap to
burner (see “Spark Rod
Gap I nspection”) .
Proceed to next page .
N
N
N
N
N
N
N
Y
Y
Y
Y
Y
Y
Y
Y
Vo l t meter set
of OHM sett i ng
CHECK SPARK
ROD RES I S T A N CE
Meter probe
Spark
rod
Meter probe
gas
v a lv e/ v entur i
Vo l t meter set
to OHM sett i ng
Spark
rod
I n l et
Pressure
Tap
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