Lennox iComfort S30 Installation And Setup Manual page 63

Initial notification of critical alerts will pop up on the home screen and will be listed under notification menu. Minor and moderate alerts are found only under the notification menu.
* Current Lennox modulating outdoor units are XC20, XP20, XC25 and XP25.
Applicable
Alert Priority
System
Code Condition
Component(s)
403 Moderate Outdoor unit
404 Critical Outdoor unit
405 Critical Outdoor Unit
406 Critical Outdoor unit
407 Critical Outdoor unit
408 Critical Outdoor unit
Furnace, air
409 Moderate handler or
outdoor unit
410 Moderate Outdoor unit
411 Critical Outdoor unit
412 Moderate Outdoor unit
Table 18. Alert Codes and Troubleshooting
Actual
Displayed Alert Component or System Operational State and Troubleshooting Tip
Text
Compressor
The compressor ran for less than three minutes to satisfy a thermostat demand.
Short-Cycling
The compressor rotor is locked up.
• Compressor rotor locked up due to run capacitor short.
Compressor
Rotor Locked
• Bearings are seized.
• Excessive liquid refrigerant, etc. (NOTE: May need to install hard start kit).
Compressor The compressor circuit is open. Compressor circuit open (due to power disconnection - open
Open Circuit fuse, etc.)
Compressor
Open Start The required amount of current is not passing through the START current transformer.
Circuit
Compressor
Open Run The required amount of current is not passing through RUN current transformer.
Circuit
Compressor
Contactor The compressor is running continuously.
Welded
The secondary voltage for the applicable system component has fallen below 18VAC.
Compressor
• Secondary voltage is below 18VAC.
Voltage Low
• If this continues for 10 minutes, the thermostat will turn off the applicable system component.
Unit low pressure is below the required limit.
Open Low • Check operating pressures.
Pressure Switch
• Low pressure switch opens at a specific pressure (system shuts down) and closes at a specific
pressure (system restarts).
The low pressure switch has opened five times during one cooling or heating demand.
• Thermostat will shut down the outdoor unit.
Low Pressure
Switch Strikes
• Open low pressure switch error count reached five strikes.
Lockout
• Check system charge using both approach and sub-cooling methods.
• Reset by putting outdoor unit control in test mode or resetting low voltage power.
The unit high pressure is above the upper limit.
• System will shut down.
Open High • Confirm that the system is properly charged with refrigerant.
Pressure Switch
• Check condenser fan motor, expansion valve (if installed), indoor unit blower motor, stuck
reversing valve or clogged refrigerant filter.
• Confirm that the outdoor unit is clean.
63
How to clear alert code
Automatically clears after four
consecutive normal compressor
run cycles.
Automatically clears after four
consecutive normal run cycles or
after power reset.
Automatically clears after one
normal compressor run cycle.
Automatically clears after current
is sensed in START sensor, or
after power reset.
Automatically clears after current
is sensed in RUN sensor, one
normal compressor run cycle, or
after power reset
Automatically clears one normal
compressor run cycle or after
power reset.
Automatically clears after voltage
is detected as higher than
20VAC for two seconds or after
power reset.
Automatically clears when the
system detects that the issue no
longer exists.
Automatically clears when the
system detects that the issue no
longer exists.
Automatically clears after the
high pressure switch closes or a
power reset