Bradford White EF60T125 Service Manual page 46

Observe burner operation through the sight glass located on the combustion insert mounting flange. Normal burner operation
should ignite smoothly, without evidence of coughing or huffing upon ignition. The burner flame should be a blue flame near the
burner surface in a uniform flame pattern. Occasional yellow or white streaks are normal.
Serial Numbers including and AFTER GB13006174 and ALL EFR models
Continued from
previous page
Refer to control board illustration,
is there 24VAC between P5(5) and P5(8) (blue and
brown wires) during the flame establishing period?
(Note: Control Display must show "Heating" for
operating status)
Can you hear or feel
gas valve energize?
Y
Turn VENTURI set screw clockwise until its
bottomed out. Turn screw counter-clockwise 6-½
turns from bottom. (Note: Venturi adjustment screw
is not on the EF100T399 models)
Y
Does burner light
smoothly, without
evidence of coughing
or huffing?
Does burner stay lit?
N
Check flame sensor,
Is there 1 to 5 micro amps
(min.) during 1.5 second
flame proving period?
(Value may be displayed on
the control display by
accessing "Service Mode")
Replace flame sensor
(see "Flame Sensor
Replacement
Procedure")
46
N
Control Board
Y
Replace Rectifier harness
N
gas valve.
(see "Gas Valve
Replacement Procedure")
N
Check for obstruction
at inlet of gas valve.
Is inlet free of
N
obstruction?
Y
Y
Call for technical
support
Does burner operate
Y
normaly until thermostat is
Y
System OK
N
120 volt potential exposure. Isolate the
appliance and reconfirm power is
disconnected using a multi-meter.
Replace
and/or
Clear obstruction
CONTROL BOARD
N
satisfied?
Y
Multimeter set to
microamp (μA) setting
WARNING
Venturi
adjustment
Inlet gas
pressure tap
N Inspect burner tube, (see
"Burner Tube Inspection")
3
1 2
2
1
6 3
8 5
1 2 3
4 1
J1 P5 P4 P9
CHECK FLAME SENSE
ROD MICROAMPS
1
1
3
5
3 1
4
P10 P2 P3 P7
Flame Sense
Terminal
Flame Sense
Rod
46