Bradford White eF Series Troubleshooting Manual And Instructions For Service page 30

Combustion System Testing and Replacement
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.
Continued from previous page.
Refer to control board illustration, is there 24VAC
between the brown and blue wires coming out of the
control board harness that routes to the gas valve
during the flame establishing period? The digital
display must show "Heating" for operating status.
Y
Can you hear or feel the
gas valve energize?
Y
Turn venturi set screw
clockwise until its bottomed
out. Turn screw counter-
clockwise 6-½ turns from
bottom.
Y
Does burner light smoothly,
without evidence of
coughing or huffing?
Y
Does the 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).
N
Replace flame sensor (see
Flame Sensor Replacement
Procedure, pg 42).
30
Service Procedure II
N
Replace the rectifier harness
N
and/or gas valve (see Gas
Valve Replacement
Procedure, pg 35).
N
Clear obstruction.
N
Check for
obstruction at inlet of
N
gas valve. Is the inlet
free of obstruction?
Y
Call Technical Support.
N
Does the burner operate
Y
normally until the
thermostat is satisfied?
Y
Y
System
O.K.
WARNING
120 volt potential exposure. Isolate the appliance and
reconfirm power is disconnected using a multi-meter.
Venturi
Replace
adjustment
control
board.
N
Inspect burner tube (see Burner
Tube Inspection, pg 33).
Inlet gas
pressure tap
30