Indoor Air Quality Control; Humidification; Dehumidification - Honeywell Home T10 Product Data

INDOOR AIR QUALITY
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).
Set up Humidification
1. Select the Humidifier Type at ISU 8000. 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
humidifier will default ISU 8070 to "Hum when Heat is
On."
A Steam humidifier will default ISU 8070 to "Tstat
controls Fan."
2. Set Window Protection setting (ISU 8050).
NOTE: Outdoor sensor temperature (Sensor or Internet
weather) is required for Window Protection (ISU 1060).
3. Select the system mode(s) to allow humidification (ISU
8060). Options are Heat and off. NOTE: Heat includes
Heat, Emergency Heat and Auto. If the system is in
Auto mode, the thermostat will allow humidification if the
last call was for heat.
4. Select from one of the Humidification Control Options
(ISU 8070).
• Hum when Heat is On
— The thermostat turns on the humidifier only if the heat
is currently running and humidification is needed.
• Hum when Fan is On
— The thermostat turns on the humidifier only if the fan is
currently running and humidification is needed.
• Tstat Controls Fan
— The thermostat turns on the humidifier and the fan
when humidification is needed.
• Hum Controls Fan
— The thermostat turns on the humidifier when
humidification is needed and the humidifier controls
the fan.
Control Humidification Level
1. Touch MENU and select Humidification.
Touch s or t to select humidity level.
2. Touch Done to save your settings.
Touch Cancel to ignore changes.
3. If frost or condensation appears on the windows, press
MENU, scroll down and select options. Then select
Window Protection Level.
Window Protection
Window Protection limits the amount of humidity to prevent
frost or condensation on windows. Window Protection (ISU
8050) requires either an outdoor sensor or use of Internet
weather (Outdoor temperature setting In ISU chart on page 32).
The thermostat prevents frost or condensation on windows by
not allowing the humidifier to run above a certain level. To
prevent frost or condensation, the thermostat may turn off the
humidifier before the humidity setting is reached.
If Window protection is enabled (ISU 8050), you can adjust
this setting by pressing MENU, then scroll down and select
Humidification > Options > Window Protection Level. Window
Protection is set on a scale from 1-10. A setting of 10
represents poorly insulated windows and a setting of 1
represents well insulated windows. A higher number
automatically reduces the humidity to help prevent frost or
condensation on your windows. Use a lower number if indoor
air seems too dry. To prevent frost/condensation on your
windows during cold outdoor temperatures, poorly insulated
windows require a higher 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 higher
number and check for frost/condensation on your windows the
next morning.
Continue to adjust the Window Protection setting to a higher
number until frost/condensation is no longer present. 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.

Dehumidification

The thermostat reads the indoor humidity level and allows the
user to set a dehumidification setting. The thermostat controls
the humidity level using the cooling system or a whole house
dehumidifier.
Dehumidification Using the Cooling System
When set for A/C with Low Speed Fan or A/C with High Speed
Fan, an overcooling limit can be set from 0 °F to 3 °F (ISU
9070). The thermostat uses the cooling system to reduce
humidity by lowering the temperature up to 3 °F below the
current cool setpoint until the desired humidity level is
reached. If set for A/C with Low Speed Fan, configure U
contacts as normally open or normally closed (ISU 9050) and
wire to the Low Speed Fan terminal on the equipment. For
example, if the U contacts are normally closed, they will open
when the thermostat calls for dehumidification. See Fig. 33.
If humidification and dehumidification are both setup to
operate in the system mode (Off), 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.
Dehumidification Overcooling Limit (ISU
9070):
This option uses the cooling system to lower the temperature
up to 3° F below the current cool setpoint until the desired
humidity is reached. The Dehum Over Cooling Limit range is
from 0° to 3° F is set for low-speed fan and 1° to 3° F if set for
high-speed fan.
Set up Dehumidification With Cooling
System
Some screens shown in this section may not appear on the
thermostat, depending on how you set up dehumidification.
55 33-00462—05