Bradford White EF-100T-399-3X - Manual (Page 52)

Hot Surface Ignition Models:
Are safety circuits in normal position?
Direct Spark Ignition Models:
Is collector high limit switch and
pressure switch in normally closed
position?
Does blower
energize?
(For Direct Spark
Ignition models,
ensure control display
shows “Heating”, raise
temperature setpoint if
necessary)
Is there 120VAC
across the white and
black wires at the
blower?
(see photo at right)
Replace blower.
(see “Blower
Replacement
Procedure”)
Y
N
Refer to ignition module/
control board illustration.
Hot Surface Ignition Models:
Is there 120VAC between
P5(1) and P5(3)?
Direct Spark Ignition Models:
Is there 120VAC between
P7(5) and P7(3)?
Repair/replace
wire harness.
Y Replace ignition module/
control board.
Y
N
N
Y
N
N
Is there 120VAC
across the white and
black wires at the
terminal block ?
Hot Surface Ignition
Models ONLY:
Refer to ignition
module, is there 24
VAC between P3(7)
and ground?
Y
N
Thermostat not
calling for heat.
(see “Thermostat
Circuit Testing”)
Correct safety circuit problem per
safety circuit trace
(section “Blocked Vent Pressure
Switch Testing”).
Y
Y
Is there 120VAC
across the white and
black wires at the
terminal block ?
(see photo at right)
N
N
Refer to ignition module/control board
illustration.
Hot Surface Ignition Models:
Is there 120VAC between P5(1) and P5(3)?
Direct Spark Ignition Models:
Is there 120VAC between P7(5) and P7(3)?
Y
Replace
ignition module/
control board.
Call technical
support.
Check amp draw through
BLACK wire lead of blower
motor. Is there .6 to 3.0
amps?
Replace blower.
(see “Blower Replacement
Procedure”)
N
Y Is Blower wheel secured to
blower motor shaft?
N
Y
Determine
power
source
problem
and
correct
52
Black wire leading to
blower motor looped
through amprobe.
120VAC check at
Terminal Block
Checking for 120VAC
(Black & White Wires)
IGNITION MODULE
HOT SURFACE IGNITION MODELS
1 2 3 8
6
5
4 3
1
1 2
1
4
1
3
3
2
1
1
5
3
P2 P4 P5 P7 P3
CONTROL BOARD
P10 P9 J1
DIRECT SPARK IGNITION MODELS
52