Bradford White UCG100H399, Руководство по обслуживанию

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T roub l es h oot i ng
120 vo l t potentia l exposure . Use caution making
vo l tage checks to avoid persona l injury .
WAR NIN G
Use caution not to damage connectors when
making vo l tage measurements or jumping termina l s
CAU TI O N
F rom previous page .
Does combustion
b l ower operate ?
Error code #67 on disp l ay . Measure vo l tage
between b l ack and white wires, of the 3 wire
harness, at the b l ower (make sure the
contro l disp l ay shows “heating” in the status
mode, if not increase the setpoint) . I s there
110 - 120 VAC ?
Rep l ace power cord/b l ower harness if
disp l ay shows “heating” and no vo l tage
is present to the b l ower .
Check that the 5 wire b l ower
modu l ation harness is p l ugged
in to the b l ower
P l ug in the wire harness . ( N ote : I f
this harness is unp l ugged b l ower
wi ll run constant l y . )
Can sparking be
seen/heard at the spark
rod to the 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
ohms . 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 and spark
rod gap to burner . (see section “Spark
Rod Gap Adjustment . ”
Does main burner l ight ?
Error code #110 on disp l ay .
See main burner l ights, no
f l ame signa l in section
“Combustion System T esting
and Rep l acement . ”
(See “Combustion System
T esting and Rep l acement”) .
Does burner continue unti l
thermostat set point is
reached ? See setting
disp l ay in Service Mode
and disp l aying
temperature sensors .
Does b l ower post - purge for
30 seconds ?
System okay
Check to see if contro l disp l ay shows any other error codes
(pressure switch, vent safety switch, or high l imit) . I f so, refer to
the appropriate section for testing and rep l acement .
Rep l ace
B l ower
Rep l ace
Contro l
Modu l e
Measure vo l tage
between ye ll ow and
green wires . I s there
17 - 30 VDC ?
N
N
N
N
N
N
N
N
Y
Y
Y
Y
Y
Y
Y
Y
Y
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