Lennox 11U61 Setup And Installation Manual page 30

Table 2. Alert Codes and Troubleshooting
Alert
Priority Alert Text
Code
(Thermostat) The thermostat is read­
ing an indoor temperature that is high­
er than 99ºF. The thermostat will not
29 Critical
allow any heating operation to begin
until it senses a temperature lower
than 99ºF.
(Thermostat) The thermostat is read­
ing an indoor temperature that is lower
than 40ºF. The thermostat will not al­
30 Moderate
low any cooling operation to begin un­
til it senses a temperature higher than
40ºF.
(Thermostat) The thermostat has lost
communication with the (furnace,
31 Critical
air­handler or outdoor unit) for more
than 3 minutes.
(Thermostat) The (furnace, air­handler
32 Moderate
or outdoor unit) is resetting itself.
(Thermostat) The thermostat does not
know the capacity (tonnage) of the
(furnace, air­handler or outdoor unit).
34 Critical
Please program the correct capacity
of the (furnace, air­handler or outdoor
unit).
507428-01
Critical alerts are displayed on Home (user) screen, in the Homeowner alert button, and in
the Installer alert button. Minor and Moderate alerts are found only in the Installer alert
button.
Steps to clear
Indoor temperature rose above 99ºF during a heating or cooling demand.
Heating operation is not allowed. Check to ensure that Heating Equipment is
not stuck ON (reversing valve, etc.). Check the accuracy of the thermostat
temperature sensor. Select cooling system mode to cool the indoor space.
Indoor Temp fell below 40ºF. Cooling operation is not allowed. Check to ensure
that cooling equipment is not stuck ON. Check accuracy of the thermostat
temperature sensor. Select heating system mode to heat the indoor space to
above 40ºF.
[Indicated unit] has not communicated with thermostat for more than 3
minutes. Check connections. Ohm wires. If fault persists, then cycle power.
Fault clears after communication is restored.
[Indicated unit] is resetting itself. This event may occur during a power outage
or power fluctuation in the system. If persistent or if it coincides with the sys­
tem operation then proceed with the following steps. Check the power connec­
tions, check the amp draw at the transformer (the transformer maybe over­
loaded) and check 24VAC voltage at the DEVICE. The alarm is only cleared
by pressing the clear button on the Installer Alerts Tab. If the fault persists after
checking the connections, replace the unit's control board.
[Indicated unit] is missing the programmed unit capacity. Go to [Indicated unit]
and program the unit capacity manually. See the unit IOM for programming
instructions. Remove power to thermostat before programming the unit control
board. Once programming is complete, reconnect thermostat wires and recon­
figure system.
30