THX9321/9421 Prestige
®
IAQ and RF EIM
23
69-2490—03
Southern Dehumidification Away Mode
This feature lowers the temperature up to 3° F below the setpoint as needed to
prevent excessive humidity while the home is unoccupied.
Southern Dehumidification Away Mode options: (ISU 9180 to 9200)
• Fan Control: Auto, On or Circulate
• Low Limit Temperature Setting: Lowest temperature allowed to control
humidity.
• Temperature Setting: Temperature is maintained when dehumidification is
not needed.
• Dehumidification Setting: Humidity level desired while Dehumidification
Away Mode is active.
You can control humidity with a dehumidifier or a cooling system. If a cooling
system is used, humidity is controlled by cooling indoor air to the Low Limit
Temperature Setting. When the desired humidity level is reached, the system will
maintain the Southern Dehumidification Away Mode temperature setting.
Ventilation
The thermostat can be set for the following ventilation types: (ISU 10000)
• ERV/HRV
• Passive (Fan Only)
• Fresh Air Damper
Ventilation Control Methods
(ISU 10060)
• ASHRAE: Operation of ventilation equipment meets the ASHRAE 62.2
Ventilation Standard based on CFM, number of bedrooms and square
footage of home. ASHRAE 62.2 is not met if the user programs the
thermostat to prevent ventilation in the Sleep program period.
• Percent on Time: The ventilator runs based on a percentage set in the
Installer Setup. For example: if set to 50%, the ventilator runs at random
times during a 1 hour period until it reaches a 50% run time (approximately
30 minutes).
Ventilation — Outdoor Condition Lockouts
(ISU 10130). The ventilator will not
operate when outdoor conditions exceed the lockout settings. Options are:
• Ventilator Low Temperature Lockout Setpoint (Off, -20° to 40° F)
• Ventilator High Temperature Lockout Setpoint (Off, 80° to 110° F)
• Ventilator High Dewpoint Lockout Setpoint (Off, 65° to 85° F)
If set to ventilate on high indoor humidity, the ventilator turns on if the indoor
humidity is 10% above the Humidification setting. (ISU 10160).
To see all ventilation options, press
MENU > INSTALLER OPTIONS > VIEW/EDIT CURRENT SETUP >
VENTILATION
.
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