Honeywell PRESTIGE THX9321 - Manual (Page 102)

THX9321 PRESTIGE ® 2.0 AND THX9421 PRESTIGE ® IAQ WITH EIM
68-0311—02 102
INDOOR AIR QUALITY (IAQ)
CONTROL
Humidification
The thermostat reads the indoor humidity level and allows the
user to set a humidification setting with or without window
protection.
The thermostat can be set up to control a humidifier in any
system mode in the Installer Setup (ISU 8060). A discharge air
sensor is required to humidify in the cool mode.
If humidification and dehumidification are setup to operate in
the same system mode (Heat, Cool, Off) and you are sensing
humidity from one location, the thermostat will automatically
enforce a 15% deadband between the humidification and
dehumidification settings. The thermostat will automatically
switch between humidification and dehumidification to maintain
the desired humidity level.
If humidification and dehumidification are setup to operate in
the same system mode (Heat, Cool, Off) and you are sensing
humidity from two different locations using a remote wireless
indoor sensor, the thermostat will allow humidification and
dehumidification to operate at the same time, and there is no
deadband between humidification and dehumidification
settings.
Window Protection
Window Protection limits the amount of humidity to prevent
frost or condensation on windows. Window Protection (ISU
8050) requires an outdoor sensor.
The maximum humidity level that is allowed (“Window Limit”) is
displayed on the Humidification Settings screen. The
thermostat prevents frost or condensation on windows by not
allowing the humidifier to run above the “Window Limit.” The
thermostat may turn off the humidifier before the desired
humidity setting is reached.The Window Limit is based on the
current outdoor temperature and the user's window protection
setting.
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 number automatically reduces the humidity
to help prevent 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 outdoor
temperatures, poorly insulated windows require a lower
Window Protection setting, which will limit how much your
humidifier can run.
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
Protection setting to a lower number until frost/condensation is
no longer present.
Fig. 206.
Fig. 207.
If Window Protection is turned Off, the thermostat controls the
humidity level to the user's desired humidity setting. Frost or
condensation may appear on windows.
Set up Humidification
1. Select the Humidifier Type at ISU 8000. See Fig. 208.
NOTE: Based on the humidifier type you select, the
thermostat defaults to the most commonly used
settings for that humidifier type.
For example, a Bypass or Fan Powered humidi-
fier will default ISU 8070 to “Humidify Only
when Fan is On.”
A Steam humidifier will default ISU 8070 to
“Humidify on Demand: Thermostat Controls
Fan.”
Fig. 208.