Annual Maintenance; Annual Summer Shutdown - Aprilaire 400 Owner's Manual

Service hot water, 140° maximum, is recommended with drain type units for
increasing capacity and for heat pump applications.
VI. ANNUAL MAINTENANCE
For best performance, we recommend that you replace the Water Panel
evaporator in your Aprilaire Humidifier annually with the exception of
Model 400 which should be changed twice a season. If you have a
Humidifier Control equipped with a water panel timer, the "Change Water Panel"
light will be lit (during operation only) when it is time to change your Water Panel.
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 control, after replacing the Water
Panel, 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.
VII. ANNUAL SUMMER SHUTDOWN
1. For Models 400, 550, and 600 close the bypass damper, which is a part
of the unit, with the use of the small damper handle. For older Model
550s without a built in damper, closer the bypass which is installed in
the bypass pipe.
2. Shut off the water supply to the humidifier by closing the saddle valve.
Humidifier Control:
There is no adjustment to the Humidifier Control required for summer
shutdown. (Applies to both Automatic and Manual Mode.)
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