Operating Instructions - Models 400M, 500M, 600M & 700M; Check The Humidifier Operation - Manual Humidifier Control - Aprilaire 300 Owner's Manual

MODELS 400M, 500M, 600M & 700M
FIGURE C: MANUAL HUMIDIFIER CONTROL
Your AprilAire Humidifier is controlled by a Manual Humidifier Control
(see FIGURE C). The Manual Humidifier Control is installed either in
the cold air return duct or on an interior wall of the home. With the
Manual Humidifier Control, it is important to anticipate a drop in
outdoor temperature and reduce the RH set point accordingly to
avoid excessive condensation, just as with the Digital Humidifier
Control installed in Manual mode (see page 8).
To determine the indoor RH, slowly turn the knob clockwise and
counterclockwise and listen for 2 clicks. The indoor RH is within the
range of the 2 clicks.
CHECK THE HUMIDIFIER OPERATION –
MANUAL HUMIDIFIER CONTROL
1. The HVAC system fan must be running for the humidifier to
function. Make a heat or fan call at your thermostat.
2. Set the knob to the highest RH set point, make sure that the water
saddle valve is open and that there is electricity to the humidifier.
3. Return control knob to the desired RH set point.
OPERATING INSTRUCTIONS –
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