Select System Setting - Honeywell RTH4300B Operating Manual

Operating Manual
Select the sytstem setting About your new thermostat
Set SYSTEM switch to control the
heating or cooling system.
The SYSTEM switch can be set to control
your heating or cooling system, depend-
ing on the season.
• Cool: Cooling system control.
• Off: All systems are off.
• Heat: Heating system control.
CAUTION: EQUIPMENT DAMAGE
HAZARD. To prevent possible
compressor damage, do not operate
cooling system when outdoor
temperature is below 50°F (10°C).