Manual for T21HTW-0

Thermostat Operation

This thermostat is very easy to operate. Set the SYSTEM switch to either EMER, HEAT, or COOL, then press the △ or ▽ buttons until the desired temperature is displayed. To turn the system off, move the SYSTEM switch to OFF and the FAN switch to AUTO.

Clock Setting: Move the SYSTEM switch to OFF, then press and hold ▽ for 5 seconds. Use △ to select settings and ▽ to shift to the next menu item (HOUR, MINUTES, WEEK DAY).

Filter Review: Move SYSTEM to HEAT or COOL, then press and hold △ and ▽ for 5 seconds to review filter running days. To clean the filter warning, press and hold △ and ▽ for 15 seconds.