Lennox iComfort S30 Installation And Setup Manual page 36

Table 1. Alert Codes and Troubleshooting
Applicable
Alert Priority
System
Code Condition
Components
270 Critical Furnace
271 Critical Furnace
272 Critical Furnace
273 Critical Furnace
274 Critical Furnace
275 Critical Furnace
276 Critical Furnace
290 Critical Furnace
Critical alerts are displayed on the Home screen, in the Homeowner alert button, and in the Installer alert button. Minor and
moderate alerts are found only in the Installer alert button.
Alert Text Component or System Operational State and Troubleshooting Tip
" This is a five strike condition during a single demand.
" Check for proper gas flow.
The furnace is in
" Ensure that igniter is lighting burner.
WatchGuard mode. The
furnace igniter cannot turn " Check flame sensor current.
on the flame.
" Check for dirty filters.
" Check for blocked CEHB or condensate drain and cracked hoses.
" This is a five strike condition during a single demand.
The furnace is in
" Check pressure (inches w. c.) of low pressure switch closing during a heat call.
WatchGuard mode. The
furnace low pressure " Measure operating pressure (inches w. c.).
switch is open.
" Inspect vent and combustion air inducer for correct operation and restriction.
" The system will go into WatchGuard mode.
" Check operation of low pressure switch to see if it is stuck open during a heat call.
The furnace low pressure
" Measure operating pressure (inches w. c.).
switch is open during run
mode.
" Inspect vent and combustion air inducer for correct operation and restriction.
" Check for blocked CEHB or condensate drain and cracked hoses.
" The system will go into WatchGuard mode.
" Check micro-amperes of flame sensor using thermostat diagnostics.
The furnace flame is go­
" Clean or replace sensor.
ing off during a heating cy­
cle.
" Measure voltage of neutral to ground to ensure good unit ground.
" Clean face of burner assembly.
" The system will go into WatchGuard mode.
The furnace limit switch
" Check firing rate and air flow.
has been open for more
than three minutes.
" Check for air blockage.
" The system will go into WatchGuard mode.
The furnace flame is out
" Shut off gas.
of sequence.
" Check for gas valve leak.
The furnace is not able to
calibrate or the high pres­
" The system will go into WatchGuard mode.
sure switch opened or
" Check vent system and pressure switch wiring connections.
failed to close in run
mode.
" The system will go into WatchGuard mode.
" Measure resistance of hot surface igniter.
There is a problem with
the furnace ignition circuit. " Replace the hot surface igniter it is not within specifications.
" Measure voltage to igniter.
36
How to clear alert code
Automatically clears on successful
ignition.
Automatically clears on successful
ignition.
Automatically clears when a heat
call ends successfully.
Automatically clears when a heat
call ends successfully.
Automatically clears when a heat
call ends successfully.
Automatically clears on successful
ignition.
Automatically clears when the fur­
nace calibrates itself successfully.
Automatically clears on successful
ignition