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TABLE 14
LED 7 Segment Status / Error Code
Integrated Control Diagnostic Codes
Press the diagnostic push button and hold it to cycle through a menu of options. Every five seconds a new menu item will be displayed.
Release the button when the desired mode is displayed.
When a solid "P" is displayed, the furnace capacity/ size is programmed.
When the solid E" is displayed, the control enters the Error Code Recall mode. Error Code Recall mode menu options: No change (display-
ing error history) remains in Error Code Recall mode; solid b" exits Error Code Recall mode; and solid c" clears the error history. Must press
button while flashing c" is displayed to clear error codes.
When the solid −" is displayed, the control enters the Field Test mode. Field Test mode menu options: Solid C" starts pressure switch
calibration; blinking −" exits Field Test mode.
Code
Diagnostic Codes/Status of Equipment
Action Required to Clear and Recover
Idle mode (Decimal blinks at 1 Hertz −− 0.5 second ON, 0.5 second OFF).
Cubic feet per minute (cfm) setting for indoor blower (1 second ON, 0.5 second
OFF) / cfm setting for current mode displayed.
Cooling stage (1 second ON, 0.5 second OFF) / 1 or 2 displayed / Pause / cfm set-
ting displayed / Pause / Repeat codes).
Dehumidification mode (1 second ON) / 1 second OFF) / cfm setting displayed /
Pause / Repeat Codes).
Variable Capacity Heat (1 second ON, 0.5 second OFF) / % of input rate displayed /
Pause/ cfm setting / Pause/ Repeat codes.
Heat Stage (1 second ON, 0.5 second OFF) / 1 or 2 displayed / Pause / cfm setting
displayed / Pause / Repeat codes.
Defrost mode.
Device communication problem − No other devices on BUS (Communication sys-
tem).
Equipment is unable to communicate. Check for mis wire
and loose connections and check for a high voltage source
of noise close to the system. (welder etc.).
Low line voltage.
Line Voltage low (Voltage lower than nameplate rating)
Check voltage.
High line voltage.
Line Voltage High (Voltage higher than nameplate rating)
Check voltage.
Line voltage frequency out−of−range.
No 60 hertz power (Check voltage and frequency).
Low 24V − Control will restart if the error recovers.
24 voltage low (Range is 18 to 30 volts) Check voltage.
Unresponsive device.
Usually caused by delay in outdoor unit responding to
indoor unit poling recycle power, check wiring.
Active communicating thermostat signal missing for more than 3 minutes.
Equipment lost communication with the thermostat. Check
connections and cycle power on the thermostat.
Control failed self−check, internal error, failed hardware. Will restart if error recovers.
Integrated furnace control not communicating. Covers hardware errors (flame sense
circuit faults, pin shorts, etc.).
Hardware problem on the control board. Cycle power on
control. Replace if problem prevents service and is persis-
tent.
Failed internal control communication between microcontrollers.
Hardware problem on the control board. Cycle power on
control. Replace if problem prevents service and is persis-
tent.
Corrupted control parameters (Verify configuration of system).
Reconfigure the system. Replace board if service (heating
/cooling) is unavailable.
Outdoor air sensor failure − NO error if disconnected. Only shown if shorted or out−
of−range.
Compare outdoor sensor resistance to temperature resist-
ance charts in installation instructions. Replace if neces-
sary.
Hard lockout − Rollout circuit open or previously open.
Correct unit cause of rollout trip or replace flame rollout
switch and test furnace operation.
Indoor blower communication failure − Unable to communicate with blower motor.
Indoor blower communication failure including power out-
age.
Indoor blower motor mis−match − Indoor motor horsepower does not match unit
capacity.
Incorrect furnace size code selected. Check unit size
codes on configuration guide or in installation instructions.
Appliance capacity / size is NOT programmed. Invalid unit codes refer to configura-
tion flow chart in installation instructions.
No furnace size code selected. Check unit size codes on
configuration guide or in installation instructions.
Gas valve mis−wired.
Check operation of gas valve.
Gas valve control relay contact shorted.
Check operation of gas valve.
Hot surface ignitor sensed open − Refer to troubleshooting in installation instruction.
Measure resistance of Hot Surface Ignitor, replace if open
or not within specification.