Operating The Aprilaire Thermostat
1.Select the mode of operation by repeatedly pressing the MODE button until the desired mode appears on the display. The heating and cooling system may be turned off by selecting the “OFF” mode. Do not set to the “OFF” mode during periods when freezing temperatures may occur.
•COOL: In the “COOL” mode a Snowflake “ 
“ icon appears on the display, which flashes when the air conditioning is running.
•HEAT: In the “HEAt” mode a Flame “ “ icon appears on the display, which flickers when the furnace is running.
•AUTO (Models 8534 and 8538 only): In the “AUtO” mode, the heating and cooling system will operate in either the “HEAt” or “COOL” mode depending on which current setting the room
temperature is closest to. Note that both the Snowflake “ | “ and Flame “ “ icons |
appear on the display. |
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