Honeywell Home THX9321 Prestige 2.0 Manual page 102

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THX9321 PRESTIGE 2.0 AND THX9421 PRESTIGE
NOTE: Heat includes Heat, Emergency Heat and
Auto. If the system is in Auto mode, the ther-
mostat will allow humidification if the last
call was for heat.
Cool includes Cool and Auto. If the system is
in Auto mode, the thermostat will allow
humidification if the last call was for cool.
A discharge sensor is required to humidify in
the Cool mode. The thermostat prevents
condensation in the duct work by not allow-
ing the humidifier to run when the discharge
temperature goes below the dew point tem-
perature. The humidifier is allowed to run
again after the discharge temperature rises
above the dew point temperature.
Fig. 215.
6. Select from one of the Humidification Control
Options (ISU 8070). See Fig. 216.
• Humidify Only when Heat is On
The thermostat turns on the humidifier only if the
heat is currently running and humidification is
needed.
• Humidify Only when Fan is On
The thermostat turns on the humidifier only if the
fan is currently running and humidification is
needed.
• Humidify on Demand: Thermostat Controls Fan
The thermostat turns on the humidifier and the
fan when humidification is needed.
• Humidify on Demand: Humidifier Controls Fan
The thermostat turns on the humidifier when
humidification is needed and the humidifier
controls the fan.
Fig. 216.
68-0311—08
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IAQ WITH EIM
7. Set the desired lockout option. See Fig. 217.
NOTE: ISU 10140 gives the option to lockout venti-
Control Humidification Level
1. Press MENU, then scroll to select Humidification.
2. Press Auto to use the humidifier to maintain your
desired humidity level.
3. Press Off to turn off the humidifier.
4. Move the slider bar to the humidity level you prefer,
then press DONE. The humidification setting range is
10–60% in 5% increments.
5. Press MORE SETTINGS if frost or condensation
appears on windows. A lower number adjusts humid-
ity to help prevent these problems. Use a higher num-
ber if indoor air is too dry.
6. To adjust the Window Protection setting, press More
Settings from the Humidification screen. Window
Protection is set on a scale from 1-10. A setting of "1"
represents poorly insulated windows and a setting of
"10" represents well insulated windows. A lower num-
ber automatically reduces the humidity to help pre-
vent frost or condensation on your windows. Use a
higher number if indoor air seems too dry. To prevent
frost/condensation on your windows during cold out-
door temperatures, poorly insulated windows require
a lower Window Protection setting, which will limit
how much your humidifier can run.
7. After you set the Window Protection setting, check for
frost/condensation on your windows in the morning.
If frost/condensation is present, adjust the Window
Protection setting to the next lowest number and
check for frost/condensation on your windows the
next morning. Continue to adjust the Window Protec-
tion setting to a lower number until frost/condensa-
tion is no longer present.
NOTE: The Window Protection option is only available if
an optional outdoor sensor is installed.
102
Fig. 217.
lation during calls for humidification. This
helps maintain the desired humidity level.