Bradford White UCG100H399, Service Manual

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3 0
1 2 0 vo l t potentia l exposure . Use caution making vo l tage
checks to avoid persona l injury . Fl ame sensor may be
too hot to hand l e, take necessary precautions .
W AR NIN G
S er vi c e P ro c e d u re V I :
F l am e S e ns or T e st i n g an d R e p l ac e m e nt
F l am e S e ns or T e st i n g P ro c e d u re
Refer to i ll ustration be l ow,
is there a minimum of 1
—
A
during 1 . 5 second f l ame
proving period ?
Y
Refer to ignition
modu l e/contro l board
i ll ustraion . ( 24 vo l ts shou l d
maintain beyond the 1 . 5
second f l ame proving period . )
I s there 24 VAC across brown
and b l ue wires coming out of
the contro l harness ?
Fl ame sensing circuit O . K .
Ca ll for technica l support .
With f l ame sensor
disconnected from ignition
modu l e, check continuity to
ground . I s there continuity
to ground ?
Rep l ace f l ame
sensor with
gasket and/or
wire l ead . (See
“ Fl ame Sensor
Rep l acement
Procedure”) .
Remove f l ame sensor from
water heater . Check
continuity from tip of f l ame
sensor to end of wire l ead .
I s there continuity ?
I s f l ame sensor free of
oxidation ?
C l ean or rep l ace f l ame
sensor . (See “ Fl ame Sensor
Rep l acement Procedure” . )
I s ceramic of f l ame
sensor cracked ?
Rep l ace f l ame sensor .
(See “ Fl ame Sensor
Rep l acement
Procedure” . )
Y
Y
Y
Y
N
N
N
N
N
Y
N
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