Automatic Mode                                                       7 - Aprilaire 300 Owner's Manual

Once blower activation mode is initiated, the humidifier and
HVAC system fan will continue to operate for 2 hours or until the
humidification set point is reached.
When the BLOWER ACTIVATION switch is in the OFF position, the
humidifier control will only operate the humidifier if the HVAC system
fan or heat is on AND if the RH is lower than the set point.
AUTOMATIC MODE
FIGURE A: ADHC (AUTOMATIC MODE)
Your AprilAire Digital Humidifier Control is installed in the cold air
return duct. During the first heating season, your humidifier control
needs to be set initially to match your home's condition. Please follow
these steps when adjusting your control (refer to FIGURE A).
1. Turn the dial setting knob to 5, which is within the normal range.
During the next 24-48 hours it may be necessary to adjust the dial
for more or less humidity, depending on your personal comfort
and home's requirements. Refer to TABLE 3: Operation Guide
2. During the coldest portion of the first heating season, minor
adjustments may be necessary. This is dependent upon your
home's construction. Refer to TABLE 3: Operation Guide
The RH in your home will now be accurately controlled to meet your
needs and should not need further adjustment during future heating
seasons. Make note of the dial setting in the event you temporarily
move the knob to OFF when performing annual maintenance of your
AprilAire Humidifier.
90-1235
7