Adams Condensing Oil-Fired Furnace - Manual (Page 20)

Circulator Blower Speeds
Low Red
Medium Blue
Hiah Black
Common/Neutral White
XII. NORMAL SEQUENCE OF
OPERATION
POWER UP MODE
The normal power up sequence is as follows:
• 115 VAC power applied to furnace
• Furnace awaits call from thermostat
HEATING MODE
The normal operational sequence in heating
mode is as follows:
• R and W thermostat contacts close,
initiating a call for heat
Closure of the thermostat switch through relay
#1 energizes primary control on the burner.
Primary control goes in the pre-purge cycle,
runs for 15 seconds and then goes into ignition
sequence, burner ignites.
Blower operation is controlled by Blower Delay
“On-Off’ Control Relay, mounted in control
panel face of blower.
With factory setting (DELAY ON MAKE) of (30
sec), approximately 30 seconds after burner
ignites, blower relay energizes to run comfort
blower in the heating speed mode.
THERMOSTAT SATISFIED
When the thermostat satisfied, heat contact
opens through relay No. 1, primary control relay
drops out, which de-energizes the primary
control. Burner goes into post-purge cycle, and
then shuts off. With factory setting (DELAY ON
BREAK) of 600 seconds, comfort blower
continues to run for approximately 390-600
seconds after burner is satisfied.
FAN ONLY MODE
The normal operational sequence in fan only
mode is as follows:
• R and G thermostat contacts close, initiating
a call for fan
• Circulator blower is energized
• Circulator blower runs
• R and G thermostat contacts open,
completing the call for fan
• Circulator blower is de-energized
• Furnace awaits next call from thermostat
COOLING MODE
When the heat-cool switch is in the cool
position, and the thermostat calls for cooling, 24
volts AC at C and Y will complete the circuit to
contactor in condensing unit.
XIII. TROUBLESHOOTING
IMPORTANT:
DUE TO THE POTENTIAL HAZARD OF
LINE VOLTAGE, ONLY A TRAINED,
EXPERIENCED SERVICE TECHNICIAN
SHOULD PERFORM THE
TROUBLESHOOTING PROCEDURE.
PRELIMINARY STEPS:
Check the diagnostic light for Indications of
burner condition. Refer to R7184 LED
Diagnostic Light section for details.
CAUTION !
When simulating a call for heat at the
R7184, disconnect at least one
thermostat lead wire from the T - T/3
terminals to prevent damage to the
themnostat. Neglecting this procedure
may burn out the heat anticipator of a
standard 24 VAC thermostat, or cause
harm to components of a micro­
electronic themnostat.
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