SETTING THE DESIRED HUMIDITY LEVEL
The control will allow you to set the desired humidity level in your home and can be used to
turn dehumidification On or Off.
Begin by pressing the ON button and ON will be displayed on the LCD Screen (see LCD display
in Figure 1). Use the arrow buttons to set the control at 59% when first installed. Allow the
dehumidifier to run until the initial setpoint has been reached, before deciding if you want to
change the humidity setting.
Raise the setting if you prefer the air to be less dry; this will reduce the amount of
time that the dehumidifier runs.
Lower the setting if you prefer the air to be more dry; this will increase the amount
of time that the dehumidifier runs.
Your comfort is the best measure of how to adjust your setting. When first installed, your
dehumidifier has to remove all the moisture that is initially in your home. The home acts like
a sponge so the moisture in the materials of your home is at the same level as the air. After
drying the air, the materials of the home will release moisture back into the air until they are
again at the same level. As a result, it is not uncommon for the dehumidifier to operate for an
extended period of time when first installed.
FIGURE 1 – Control Display and User Buttons
LCD Display
Mode Buttons – Use
to turn control On/Off. Buttons – Use to view
and set humidity setting.
Energy Savings Tip #1: Adjust the setting to be as high as is comfortable to reduce
dehumidifier run time – if it feels clammy or smells damp or moldy lower the setting. To
save energy, turn the dehumidifier control OFF when you open your windows just as you
would with air conditioning.
Energy Savings Tip #2: If vacating your home for an extended period in the summer, set
the RH at 59% and set your thermostat to as high as you are comfortable setting it in the
cooling mode. Consult with appropriate professionals regarding the highest temperature
that is safe for your pets or possessions. This will keep the humidity at a controlled level
to help prevent mold while minimizing the amount of cooling energy used.
Thank you for your purchase of the Aprilaire®Model 75 Dehumidifier Control. Your control
allows you to set the relative humidity level for your home and provides control of the
dehumidifier from a convenient living space location. The Model 75 uses an onboard sensor
to monitor the relative humidity in the space in which it is located and displays the measured
relative humidity on the digital display.
TURNING CONTROL ON/OFF
FIGURE 3 – ON/OFF Buttons
•PressingtheONbuttonwillturnonthecontrol.
•PressingtheOFFbuttonwillturnoffthecontrol.
•Thecontrolwillcontinuetodisplaythemeasured
humidity when OFF.
•Thehumiditysettingcannotbechangedwhenthe
control is OFF.
FIGURE 2 – LCD Display
90-1636
Blinking ON +*: Control Limit Exceeded.
See Control Limits, page 5.
Solid ON:
Control On
Blinking ON:
Dehumidifying
Numbers show
current room humidity
OR humidity setting
SET is displayed
when or is
pressed. The value
displayed is the
humidity setting.
See Figure 5.
OFF: Control Off
LCD DISPLAY
