Installations Instructions
50
LED LED Stat us Indication Possible Causes Cor r ective Action(s) Notes & Cautions
Off • Normal condition • None • None • None
• Control power up
• Learn button depressed
Rapid Flashing • Normal network traffic • Control is “talking” on
network as expected
• None • None
• Data 1 and data 2 wires reversed
at furnace, thermostat or
communicating compatible
outdoor AC/HP
•Check communications
wiring (data 1/ data 2
wires).
•Turn power OFF prior to
repair.
• Short between data 1 and
data 2 wires.
•Check wire connections at
terminal block
• Verify wires at terminal
blocks are securely twisted
together prior to inserting
into terminal block.
• Short between data 1 or
data 2 wires and R
(24VAC) or C (24VAC
common).
•Check data 1/ data 2
voltages.
•Verify data 1 and data
voltages as described above
Red
Communications
LED
2 Flashes • Out-of-box reset • None • None
Green
Receive
LED
On Solid • Data 1/ Data 2 miss-
wire
SYSTEM TROUBLESHOOTING
NOTE: Refer to the instructions accompanying the ComfortNet
compatible outdoor AC/HP unit for troubleshooting information.
Refer to the Tr oubl eshoot i ng Codes for a listing of possible
furnace error codes, possible causes and corrective actions.
FAULT RECALL SEQUENCE
• Only allowed in standby mode while display is
showing ON.
• Hold fault recall push-button for 2-5 seconds (until
display is blank) and then release.
• Display will then be blank for 2 seconds before
displaying faults stored in history.
• All faults are displayed one time, from most recent
to least recent.
• A Maximum of 3 consecutive faults of the same
type will be logged.
• Each error is displayed for 2 seconds, with a blank
screen for 1 second in between.
• When all errors have been displayed, the display
returns to ON.
FAULT CLEAR SEQUENCE:
• Only allowed in standby mode, while display is
showing ON.
• Hold fault recall push-button for 5-10 seconds
(until display starts flashing “—”) and then release.
• All faults in the history will have been cleared,
and display returns to ON.
• If you hold the button for longer than 10 seconds,
the display will return to ON and the faults will
not be cleared.
N
ORMAL
S
EQUENCE
OF
O
PERATION
POWER UP
The normal power up sequence is as follows:
• 115 VAC power applied to furnace.
• Integrated control module performs internal checks.
• Integrated control module monitors safety circuits
continuously.
• Furnace awaits call from thermostat. Dual 7-segment
LED’s display O
while awaiting call from thermostat.
HEATING MODE
The normal operational sequence in heating mode is as fol-
lows:
• Thermostat contacts close, initiating a call for heat.
• Integrated control module performs safety circuit
checks.
• Induced draft blower is energized on high speed for a
15-second prepurge.
• Induced draft blower steps to low speed following
prepurge. Low stage pressure switch contacts are
closed.
• Igniter warm up begins upon step to low speed and
presence of closed low stage pressure switch contacts.
• Gas valve opens at end of igniter warm up period,
delivering gas to burners and establishing flame.
• Integrated control module monitors flame presence.
Gas valve will remain open only if flame is detected.
• The percentage of heating demand is sent from the
furnace control board to determine what RPM the
draft inducer should run at. A higher percentage
demand will drive the inducer RPM higher. This will
cause the gas valve to modulate higher. The burner
will modulate based on the inducer speed