For Best Performance; Thermostat Operation - Aprilaire 8556 Owner's Manual

110-791B 7/12/01
The Aprilaire Model 8556 thermostat is designed for accurate temperature control and easy operation.
The following guidelines should be followed to ensure proper operation of the thermostat:
1. When the thermostat is operating, close the cover to allow for proper air circulation over the
temperature sensor.
2. Do not place anything which can give off warm or cool air, such as candles or portable
humidifiers, near the thermostat.
3. Although the thermostat is internally equipped to prevent short cycling of the furnace and air
conditioner, it is possible to inadvertently override this protection. Do not start, stop, and restart
the equipment without allowing a minimum of 2 minutes between heating or cooling cycles.
The Model 8556 is a full-featured thermostat which allows for additional control and operations after
basic time and temperature programming is completed. In addition to the programming buttons used
to set up all event times and temperatures, additional buttons control the following functions:
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For Best Performance

Thermostat Operation

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