PRO TH3110D / TH3210D
5
The SYSTEM switch can be set to control
your heating or cooling system, depending
on the season.
• Cool: Cooling system control.
• Off: All systems are off.
• Heat: Heating system control.
• Em Heat: Emergency & Auxiliary Heat
control. Compressor is locked out.
(Select models only.)
System switch
Set SYSTEM switch to control the
heating or cooling system.
CAUTION: EQUIPMENT DAMAGE HAZARD.
Do not operate cooling system when outdoor
temperature is below 50°F (10°C).