White-Rodgers 70 Series Thermostat Line Extension
22
This switch controls the main
blower sequence of operation
•
GAS
– equipment operates fan on a
call for heat
-
Typically for fossil fuel furnaces
•
ELEC
– thermostat operates the fan
on a call for heat
-
Typically for electric furnaces or
heat pumps
Application Switches
Conventional Models
Gas / Elec Switch
Heat Pump
O / B Switch
This switch controls the position
of the reversing valve
•
“O”
position – energizes reversing
valve in the cooling mode
•
“B”
position – energizes the
reversing valve in the heating mode
These switches are on the back of the thermostat and must be configured correctly for the application
.