Lennox SL280DFV Installation Instructions Manual page 49

Integrated Control Diagnostic Codes (continued)
Code Diagnostic Codes/Status of Equipment
E 105 Device communication problem − No other devices on RS BUS (Commu-
nication
system).
E 110 Low line voltage.
E 111 Line voltage polarity reversed.
E 112 Ground not detected
E 113 High line voltage.
E 114 Line voltage frequency out−of−range.
E 115 Low 24V − Control will restart if the error recovers.
E 116 High 24V.
E 117 Poor ground detected (Warning only)
E 120 Unresponsive device. Communication only.
E 124 Active communicating thermostat signal missing for more than 3 min-
utes.
E 125 Control failed self−check, internal error, failed hardware. Will restart if
error
recovers. Integrated control not communicating. Covers hardware errors
(flame sense circuit faults, pin shorts, etc.).
E 126 Control internal communication problem.
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 mis−
wired and/or loose connections between the stat,
indoor unit and outdoor unit. Check for a high volt-
age 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−rob-
bing 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 con-
trol 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 wir-
ing connections. Cleared after unresponsive device
responds to any inquiry.
Equipment lost communication with the thermostat.
Check four wiring connections, ohm wires and cycle
power at the thermostat. Alert stops all services and
waits for heartbeat message from thermostat (sub-
net controller). Cleared after valid thermostat (sub-
net controller) message is received.
Hardware problem on the control. Cycle power on
control. Replace if problem prevents service and is
persistent. Critical alert. Cleared 300 seconds after
fault recovered.
Hardware problem on the control. Cycle power on
control. Replace if problem prevents service and is
persistent. Cleared 300 seconds after fault recov-
ered.
Page 49
Action Required to Clear and Recover