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IV. ANNUAL MAINTENANCE

For best performance, we recommend that you replace the

water panel evaporator in your Aprilaire Humidifier annually.

•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.
V. ANNUAL SUMMER SHUTDOWN
1. For Models 448, 558, 568, and 600 close the bypassdamper if
provided. The Model 600 damper is built into the unit and is
easily closed with the small damper handle.
2. Shut off the water supply to the humidifier by closing the sad-
dle valve.
Humidifier Control:
There is no adjustment to the Humidifier Control required for
summer shutdown. (Applies to both Automatic and Manual
Mode.)
VI. PERIODIC PREVENTATIVE MAINTENANCE
NOTE: Periodic inspection and preventive maintenance
of your total heating system is important for efficient and safe opera-
tion. Your heating contractor should include humidifier service at the
same time.
All models are equipped with an in-line water strainer and orifice as
shown below. These parts should be inspected and cleaned periodi-
cally to assure continued proper unit performance.