Flame Sensor Testing And Replacement - Bradford White EF Series Service Manual

Flame Sensor Testing Procedure
Flame Sensor Testing Procedure
Disconnect flame sensor wire lead
from ignition module and check
continuity to ground.
Is there continuity to ground?
Refer to illustration below, is there
a minimum of 1 micro amp during
1.5 second flame proving period?
Remove flame sensor from heater.
Check continuity from tip of flame
sensor to end of wire lead.
Is there continuity?
With flame sensor Disconnected
from ignition module, check
continuity to ground.
Is there continuity to ground?
Refer to illustration below, is there
a minimum of 1 micro amp during
1.5 second flame proving period?
Remove flame sensor from heater.
N
Check continuity from tip of flame
sensor to end of wire lead.
Is there continuity?
Y
Is flame sensor free
Is flame sensor free
of oxidation?
of oxidation?
N
N
Clean or replace
Clean or replace
flame sensor.
flame sensor.
(see pg 33)
(see pg 33)
Meter probe
Meter probe
Meter probe
Flame sensor
Flame sensor
Flame sensor
terminal
terminal
terminal
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Flame Sensor Testing and Replacement

Flame Sensor Testing and Replacement
Replace flame sensor
Y
N
Y
N
N
Replace flame sensor
Y
Y
Refer to ignition module illustration below. Is
Y there 24 volts AC at locations P3(2) & P3(5),
N
24 volts should maintain beyond the 1.5
N
Y Is ceramic of flame
Y Is ceramic of flame
sensor cracked?
sensor cracked?
Y
Y
Replace flame sensor.
Replace flame sensor.
(see pg 33)
(see pg 33)
Volt meter set to
Volt meter set to
Volt meter set to
Micro amps setting
Micro amps setting
Micro amps setting
(µA)
(µA)
(µA)
Service Procedure EF-VIII
Service Procedure EF-VIII
with gasket
and/or wire lead.
(see pg 33)
Refer to ignition module illustration below. Is
there 24 volts AC at locations P3(2) & P3(5)?
24 volts should maintain beyond the 1.5
second flame proving period.
with gasket
and/or wire lead.
(see pg 33)
second flame proving period?
N
Call for
technical support
N
N
Flame sensor
Flame sensor
terminal on
terminal on
ignition module.
ignition module.
WARNING
WARNING
120 volt potential exposure. Use caution
120 volt potential exposure. Use caution
making voltage checks to avoid
making voltage checks to avoid
personal injury.
personal injury.
Y
Flame sensing circuit OK
N
Call for
technical support
Y
Flame sensing circuit OK
Flame sensor terminal
on ignition module.
Meter probe
Meter probe
Meter probe
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