User's Manual

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There are 2 possible modes of operation of your Aprilaire Humidifier Control
– Automatic and Manual. An explanation of both modes follows:
Automatic Mode: (Manual Mode-see pg 5)
Your Aprilaire 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 1 – 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 1 – Operation Guide”.
TABLE 1 – Operation Guide
Condition Solution
Condensation on windows Reduce the setting on the control dial
by 1 increment.
Lack of humidity Increase the setting on the control dial
by 1 increment.
Humidifier does not operate Turn dial to “Test/Reset.” Make certain
furnace is operating in heat mode.
If humidifier still doesn’t operate,
contact your heating contractor.
Humidifier won’t shut off Turn dial to “Off.” If humidifier
continues to operate, contact your
heating contractor.
Test mode System operation is checked by setting
the knob to “Test/Reset.” Make certain
furnace blower is operating and furnace
is calling for heat. Humidifier will
operate for one minute. Be sure to turn
the control knob back to the prior setting
after checking humidifier operation.
Reset Water Panel change Turn the control knob to the
“Test/Reset” position until the “Change
Water Panel” light blinks to reset the
water panel change indicator timer.
(Blower must be operating and furnace
calling for heat.) Be sure to turn the
control knob back to the prior setting
after resetting the timer.
indicator
TABLE OF CONTENTS
OPERATING INSTRUCTIONS – MODELS 400, 600 & 700