PRO TH4110B Programmable Thermostat
7
System switch
The SSYYSSTTEEMMswitch can be set to con-
trol your heating or cooling system,
depending on the season.
•HHeeaatt::Thermostat controls only
the heating system.
•CCooooll::Thermostat controls only
the cooling system.
•OOffff::Heating and cooling
systems are off.
Set SSYYSSTTEEMMswitch to control the heating or
cooling system.
CAUTION: EQUIPMENT DAMAGE
HAZARD. To prevent possible
compressor damage, do not operate
cooling system when outdoor
temperature is below 50°F (10°C).