VISIONPRO
®
IAQ TOTAL HOME COMFORT SYSTEM
68-0287—04
22
DEHUMIDIFICATION DROOP CONTROL
In extremely high humidity conditions, the thermostat keeps
the air conditioner running (energizing Y/Y2 and G) for up to
3°F below the temperature setpoint. It does this while trying to
achieve the desired humidity setpoint and balancing that with
the temperature setpoint. The thermostat controls up to 3° F
below the temperature setting until either the humidity setpoint
is satisfied or conditions change.
With Whole House Dehumidifier
Controls humidity levels in the house by dehumidifying without
the use of the air conditioner. This setting requires a dedicated
unit for dehumidification. Dehumidification with a whole house
dehumidifier will take place when the thermostat is in the Cool,
Off, Auto, Heat or Em.Heat modes. If the system is installed
with a whole house humidifier, dehumidification with a whole
house dehumidifier will only take place when the thermostat is
in Cool, Off or Auto modes (Auto only if the previous call was a
call for cooling).
When controlling a whole-house dehumidifier the user can
toggle between auto (dehumidify when needed based on
setpoint and current humidity level) and off (see Fig. 29).
Fig. 29. Display when controlling a whole-house
dehumidifier.
1.
Press the More key until the inside humidity percent and
dehumidification setpoint are shown.
2.
Use Up and Down arrow keys, located to the right of the
dehumidifier setpoint, to set desired humidity level for
dehumidification in the summer.
3.
Press Done key.
Ventilation Control
Ventilation setup options include ISUs 400, 401, 402, 403, and
404. Combined, these will determine a percentage of
maximum ventilation limit. The thermostat will calculate
whether or not this level of ventilation meets ASHRAE
standard 62.2. If ASHRAE 62.2 is met a P will appear in the
display above the setup number. If ASHRAE 62.2 is not met an
F will appear in the display above the setup number.
Passing ASHRAE 62.2 is only applicable when vent is running.
For example, if installer has set to not vent during sleep period,
ASHRAE 62.2 would be met at all times except during sleep
period.
Ventilation occurs two ways:
AUTOMATIC
Uses installer setup to determine amount of ventilation
required based on house and equipment size. To disable
automatic ventilation, switch the ventilation setting to Off. The
user can still use the timer to request ventilation.
ON DEMAND
User can also set a vent timer that will circulate fresh air into
the home for a set period of time from 20 to 180 minutes in 20-
minute increments. The vent timer is enabled whether
ventilation is set to “Auto” or “Off.”
VENTILATION IN HIGH HUMIDITY CONDITIONS (SETUP FUNCTION 0406)
If Ventilation Control is available (setup function 0400 set to 1
or 2), this allows the ventilation equipment to turn on if the
humidity rises approximately 10% above the RH setting in
heating mode to exhaust the extra humidity.
HEAT PUMP OPERATION
Heat Pump LED Indication
A red LED indication is located in the upper right corner of the
thermostat. It is only visible when lighted.
When the L terminal is wired to an equipment monitor, the LED
signals when a check or fail signal is sent to the thermostat
from the system. This is operational in the Heat, Off, Cool or
Auto positions.
MORE
DONE
CANCEL
DEHUMIDIFIER
Inside
Humidity
M23515
DONE
M23520
MORE
DONE
CANCEL
VENT
Minutes
M23519
