FOR HVAC INSTALLER ONLY AND HOMEOWNER
Operation
The initial dead band setting (the range that the dehumidifier
cycles on and off) is 3%. With a setpoint of 50%, the dumidifier
turns on when the reading reaches 53%. The dehumidifier
continues to remove water from the air until the reading is
47%. The dehumidifier remains off until the reading is 53%.
If the setpoint is equal to or greater than the current ambient
condition, the space does not need to be dried so the
dehumidifier function will be off.
Example: Setpoint: 50% RH
Current condition: 45% RH = Dehumidifier off, the
“
O
”
indicator will not be shown.
If the setpoint is less than the ambient condition, the
dehumidifier will be on and the red “DEHU” indicator will be
lit. Since the space is more humid than the set point, the
controller operates the dehumidifier to dry the space.
Example: Setpoint: 50% RH
Current condition: 55% RH = Dehumidifier on, the
“
O
”
indicator will be shown.
To set the relative humidity setpoint, press up or down
“RH”
buttons to adjust the relative humidity setpoint as desired.
Therma-Stor recommends relative humidity levels not exceed
50% in the summer, and 25-35% in the winter if you live
in a cold climate. It is not recommended that the humidity
setpoint be set below 35%. In order to dry the home in the
winter in a cold climate, use the ventilation function of the
system rather than the dehumidifier function. Call the factory
or refer to the owner’s manual for more information.
5.3F Fan Setting and Operation
Use the
“FAN”
button to adjust the fan operation. There are
2 choices for fan operation:
“ON”
or
“AUTO.”
“ON”
– indicates the fan of the Ultra-Aire will run
continuously. This does not affect either the dehumidification
or ventilation functions of the system. In other words, the
system may or may not be ventilating or dehumidifying while
the fan is running. Common reasons for operating the fan
continuously are filtration and air recirculation.
“AUTO”
– indicates the fan will run when the control calls for
dehumidification or ventilation. If the control has not called for
dehumidification for 3 hours, the control will automatically run
the fan for 10 minutes. The fan must run a specific amount of
time per day. This helps to keep the dehumidifier dry.
After dehumidification cycle, fan automatically shuts off for 10
minutes.`
To set the operation:
1. Press and hold the
“FAN”
button. The current fan setting
will begin to flash. Release the button.
2. Press the
“FAN”
button to toggle between the
“ON”
and
“AUTO”
modes.
An
“
O
”
indicator indicates the fan is operating. A flashing
“
O
”
indicator indicates the fan is in a wait mode and will
operate shortly. No
“
O
”
indicates the fan is off.
With the fan in the
“AUTO”
mode, the fan will operate only
when needed by other functions of the system. The fan
will remain off unless the system is dehumidifying and/or
ventilating. The fan always runs during dehumidification and
ventilation and the fan
“
O
”
icon will be lit. To completely turn
the system off, use the
“ON/OFF”
button as described earlier.
To adjust the ventilation mode see Section 3.7.
5.3G Damper Operation and Setting (Ventilation)
Manual/Hold Mode
Ultra-Aire units can be installed to incorporate optional ventilation.
The damper setting controls the ventilation function of the system.
It has no control over the dehumidification function, although
the ventilation function can and should be used to dry the space
depending on the climate and the outside air conditions. Refer to
the appropriate Ultra-Aire manual for more information.
In order to provide ventilation, the damper must be open (
“ON”
)
and the fan must be running. The controller takes care of these
two functions automatically, so that whenever the damper is open
(
“ON”
), the fan is running.
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Ultra-Aire 90H Installer’s & Owner’s Manual
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Ultra-Aire 90H Installer’s & Owner’s Manual
