Lennox SLP99UHV Series Unit Information page 30

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 (displaying 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
.
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
A
second OFF) / cfm setting for current mode displayed.
Cooling stage (1 second ON, 0.5 second OFF) / 1 or 2 displayed / Pause /
C
cfm setting displayed / Pause / Repeat codes).
Cooling stage (1 second ON, 0.5 second OFF) / 1 or 2 displayed / Pause /
d
cfm setting displayed / Pause / Repeat codes).
Variable Capacity Heat (1 second ON, 0.5 second OFF) / % of input rate
h
displayed / Pause/ cfm setting / Pause/ Repeat codes.
Heat Stage (1 second ON, 0.5 second OFF) / 1 or 2 displayed / Pause / cfm
H
setting displayed / Pause / Repeat codes.
df
Defrost mode.
U Discharge air temperature
- Soft disable - Soft disabling is when thermostat finds a device on the BUS
that it does not recognize and the thermostat sends a the device a message
-
to be in soft disabling mode until properly configured. Two horizontal bars
will display.
Device communication problem - No other devices on BUS (Communication
system).
E105
Low line voltage.
E110
High line voltage.
E113
E114 Line voltage frequency out-of-range.
Low 24V - Control will restart if the error recovers.
E115
Unresponsive device.
E120
Active communicating thermostat signal missing for more than 3 minutes.
E124
Control failed self-check, internal error, failed hardware. Will restart if error
E125 recovers. Integrated furnace control not communicating. Covers hardware
errors (flame sense circuit faults, pin shorts, etc.).
Failed internal control communication between microcontrollers.
E126
Outdoor air sensor failure - NO error if disconnected. Only shown if
E180
shorted or out-of-range.
TABLE 14
LED 7 Segment Status / Error Code
Page 30
Action Required to Clear and Recover
Steps to follow if the damper control module is
displaying the soft disable code.
Confirm proper wiring between all devices
(thermostat, damper control module, indoor and
outdoor).
Cycle power to the control that is displaying the soft
disable code.
Put the room thermostat through set up.
Go to setup / system devices / thermostat / edit /
then push reset.
Go to setup / system devices / thermostat / edit /
then push resetAll.
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.).
Line Voltage low (Voltage lower than nameplate
rating) Check voltage.
Line Voltage High (Voltage higher than nameplate
rating) Check voltage.
No 60 hertz power (Check voltage and frequency).
24 voltage low (Range is 18 to 30 volts) Check
voltage.
Usually caused by delay in outdoor unit responding
to indoor unit poling recycle power, check wiring.
Equipment lost communication with the thermostat.
Check connections and cycle power on the
thermostat.
Hardware problem on the control board. Cycle
power on control. Replace if problem prevents
service and is persistent.
Hardware problem on the control board. Cycle
power on control. Replace if problem prevents
service and is persistent.