Additional Information For All Models; Effect Of Water Characteristics; Annual Maintenance - Aprilaire Humudifiers 400A Owner's Manual

ADDITIONAL INFORMATION FOR ALL MODELS

Be sure to keep fireplace dampers closed when not in use. They provide an
excellent escape route for heat, as well as humidity.
On occasion, indoor moisture producing activities such as clothes drying,
cooking, showers, etc., may raise the RH level higher than it should be, even
though the Aprilaire humidifier is not operating. Telltale indications are
condensation or frost on cold surfaces such as windows, doors, walls, etc. If
such condensation persists for several hours, your home should be ventilated
to dissipate the potentially damaging excess moisture.

EFFECT OF WATER CHARACTERISTICS

Your humidifier is designed to operate using hot, cold, hard or mechanically
softened water. (Hot water is required for Models 350 and 360.)
Water contains varying amounts of minerals. The residue remaining as a
result of hard water evaporation is primarily calcium and magnesium
components and is usually quite hard, scaly, and dense.
Residue from softened water tends to be soft and fluffy and has a greater
volume than hard water deposits. In either case, the service life of a Water
Panel evaporator will be the same. The Water Panel evaporator should be
changed at least once a year with the exception of the Model 400A which
should be changed at least twice a heating season. In the drain-equipped
models, most of the mineral solids are controlled by flushing them down
the drain.
Hot supply water, 140°F maximum, is recommended with drain type
humidifiers for increasing capacity and is required for heat pump and air
handler applications.
WARNING
RISK OF SCALDING. Water temperature over 125˚F can cause severe
burns and scald instantly. Shut off the hot water supply before
disconnecting or tapping into any hot water supply line.
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ANNUAL MAINTENANCE

For best performance, we recommend that you replace the Water
Panel evaporator in your Aprilaire humidifier at least annually with
the exception of Model 400A which should be changed at least
twice per heating season.
The "Change Water Panel" indicator light (Automatic Control only) will blink
when it is time to change your Water Panel. See individual model instructions
for additional maintenance.
To purchase a new Water Panel:
• Call the installer of your Aprilaire humidifier.
This information is often found on your equipment.
• Call your heating and air conditioning dealer.
• Use our "Dealer Locator" at: www.aprilaire.com
• Look in the Yellow Pages under Humidifying Apparatus or
Heating & Air Conditioner Contractors.
• If none of the above is successful and you still need information,
please feel free to write us.
• Purchase only Genuine Aprilaire Water Panels to maintain performance.
If your humidifier is equipped with an Automatic Humidifier Control with
Water Panel change indicator, after replacing the Water Panel, turn the
control knob to the "Test/Reset" position until the "Humidifier On" light blinks
to reset its timer. (Blower must be operating and HVAC calling for heat.) Be
sure to turn the control knob back to it's original setting. If the "Humidifier On"
light continues to blink, your humidifier is in Test mode. DO NOT LEAVE THE
CONTROL IN TEST MODE OR HUMIDIFIER WILL NOT OPERATE.
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