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D
Burner motor is de−energized.
4.
Action: Established flame fails
Response:
D
Burner motor is de−energized and oil primary con-
trol goes into recycle mode.
D
If the fan off delay is longer than the recycle timing,
the heat fan continues to run through the next trial
for ignition.
5.
Action: Limit Switch Opens
Response:
D
Oil primary control shut off the burner.
D
Circulating fan is energized immediately at cool
speed.
D
A15 control board opens oil primary control T−3T
connections.
D
Circulating fan runs as long as limit stays open.
6.
Action: Limit Switch Closes
Response: If there is a heat demand, A15 control
board energizes oil primary control, initiating burner
light off.
Troubleshooting
Burner failure or improper operation can result from a num-
ber of different causes. Often the cause can be pinpointed
by observing the different types of failure or by the process
of elimination. The following troubleshooting charts list
some failures, causes and a sequence of steps to isolate
the point of failure. Check the simplest and most obvious
items before progressing to other items.
Troubleshooting: Burner fails to start
Source
Procedure
Causes
Correction
Thermostat
Check thermostat settings.
Thermostat in
OFF
or
COOL
Switch to
HEAT
.
Thermostat is set too low
Turn thermostat to higher temperature.
Safety
Overloads
Check burner motor,
primary safety control, &
auxiliary limit switch.
Burner motor overload
tripped
Push reset button pump motor.
Primary control tripped on
safety
Reset primary control.
Auxiliary limit switch tripped
on safety
Reset auxiliary limit.
Power
Check furnace disconnect
switch & main disconnect.
Open switch
Close switch.
Blown fuse or tripped circuit
breaker
Replace fuse or reset circuit breaker.
Thermostat
Touch jumper wire across
thermostat terminals on
primary control. If burner
starts, then fault is in the
thermostat circuit.
Broken or loose thermostat
wires
Repair or replace wires.
Loose thermostat screw
connection
Tighten connection.
Dirty thermostat contacts
Clean contacts.
Thermostat not level
Level thermostat.
Faulty thermostat
Replace thermostat.
CAD Cell
Disconnect the flame
detector wires at the
primary control. If the
burner starts, fault is in the
detector circuit.
Flame detector leads are
shorted
Separate leads.
Flame detector exposed to
light
Seal off false source of light.
short circuit in the flame
detector
Replace detector.
table continued on next page
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