Lennox SL280UH090V36B Installation Instructions Manual page 50

Integrated Control Diagnostic Modes
Code Diagnostic Codes/Status of Equipment
. Idle mode (Decimal blinks at 1 Hertz -- 0.5
second ON, 0.5 second OFF).
A Cubic feet per minute (cfm) setting for
indoor blower (1 second ON, 0.5 second
OFF) / cfm setting for current mode
displayed.
C Cooling stage (1 second ON, 0.5 second
OFF) / 1 or 2 displayed / Pause / cfm
setting displayed / Pause / Repeat codes).
d Dehumidification mode (1 second ON) /
1 second OFF) / cfm setting displayed /
Pause / Repeat Codes).
h Heat pump stage (1 second ON, 0.5
second OFF) / % of input rate displayed
/ Pause / cfm setting / Pause / Repeat
codes.
H Gas Heat Stage (1 second ON, 0.5 second
OFF) / 1 or 2 displayed / Pause / cfm
setting displayed / Pause / Repeat codes.
Blinking during ignition.
dF Defrost mode.
U Discharge Air Temperature
E105 Device communication problem - No other
devices on RS BUS (Communication
system).
E110 Low line voltage.
E111 Low line voltage.
E112 Ground not detected
E113 High line voltage.
E114 Line voltage frequency out-of-range.
E115 Low 24V - Control will restart if the error
recovers.
E116 High 24V.
E117 Poor ground detected (Warning only)
E120 Unresponsive device. Communication
only.
Action Required to Clear and Recover
Equipment is unable to communicate. Indicates numerous message
errors. In most cases errors are related to electrical noise. Make sure
high voltage power is separated from RSBus. Check for miswired and/or
loose connections between the stat, indoor unit and outdoor unit. Check
for a high voltage source of noise close to the system. Fault clears after
communication is restored.
Line Voltage Low (Voltage lower than nameplate rating). Check power line
voltage and correct. Alarm clears 5 seconds after fault recovered.
Reverse line power voltage wiring. System resumes normal operation 5
seconds after fault recovered.
System shuts down. Provide proper earth ground. System resumes normal
operation 5 seconds after fault recovered.
Line Voltage High (Voltage higher than nameplate rating). Provide power
voltage within proper range. System resumes normal operation 5 seconds
after fault recovered.
No 60 Hertz Power. Check voltage and line power frequency. Correct
voltage and frequency problems. System resumes normal operation 5
seconds after fault recovered.
24-Volt Power Low (Range is 18 to 30 volts). Check and correct voltage.
Check for additional power-robbing equipment connected to system. May
require installation of larger VA transformer to be installed in furnace / air
handler. Clears after fault recovered.
24 Volt Power High (Range is 18 to 30 volts). Check and correct voltage.
Check for proper line voltage (120V, 240V, etc.) to equipment. Clears when
control senses proper voltage.
Provide proper grounding for unit. Check for proper earth ground to the
system. Warning only will clear 30 seconds after fault recovered.
Usually caused by delay in outdoor unit responding to indoor unit poling.
Recycle power. Check all wiring connections. Cleared after unresponsive
device responds to any inquiry.
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