Aprilaire 8553 Thermostat User Manual


 
– 22 –
If the thermostat does not respond when a button is pushed it may be because the keypad has been
locked. A Lock icon “ “ will appear when a button other than OUTDOOR is pushed if the keypad
has been locked.
No. 5 – Fan with Heat Call. This switch was set by the installing contractor to operate the thermostat
properly with your equipment. Do not change the position of this switch without consulting with the
installing contractor.
110-790B 7/11/01 3:11 PM Page 24