4, Action: Established flame fails
Response:
•Burner motor is
•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:
•Oil primary control shut off the burner.
•Circulating fan is energized immediately at cool speed.
•A15 control board opens oil primary control
•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.
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.
Source
Thermostat
Safety
Overloads
Power
Thermostat
CAD Cell
Primary Control
Procedure
Check thermostat settings.
Check burner motor, primary safety control, & auxiliary limit switch.
Check furnace disconnect switch & main disconnect.
Touch jumper wire across thermostat terminals on
primary control. If burner starts, then fault is in the thermostat circuit.
Disconnect the flame detector wires at the
primary control. If the burner starts, fault is in the detector circuit.
Place trouble light between the black and white leads.
No light indicates that no power is going to the control.
Place trouble light between the orange and white leads. No light indicates faulty control.
Causes
Thermostat in OFF or
COOL
Thermostat is set too low
Burner motor overload tripped
Primary control tripped on safety
Auxiliary limit switch tripped on safety
Open switch
Blown fuse or tripped circuit breaker
Broken or loose thermostat wires
Loose thermostat screw connection
Dirty thermostat contacts
Thermostat not level
Faulty thermostat
Flame detector leads are shorted
Flame detector exposed to light
short circuit in the flame detector
Primary or auxiliary control switch is open
Open circuit between disconnect switch and limit control
Low line voltage or power failure
Defective internal control circuit
Correction
Switch to HEAT.
Turn thermostat to higher temperature.
Push reset button pump motor.
Reset primary control.
Reset auxiliary limit.
Close switch.
Replace fuse or reset circuit breaker.
Repair or replace wires.
Tighten connection.
Clean contacts.
Level thermostat.
Replace thermostat.
Separate leads.
Seal off false source of light.
Replace detector.
Check adjustment. Set the maximum setting.
Jumper terminals; if burner starts, switch is faulty, replace control.
Trace wiring and repair or replace it.
Call the power company.
Replace the control.
table continued on next page
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O23V SERIES
