Thursday, July 21, 2022 at 3:25 PM
We added a pair of switches to our furnace. The top one controls the green fan which pulls outside air in through the open windows (the fan is in the basement and exhausts the air through an old chimney) The bottom one controls the furnace's fan which we keep running 24/7. This makes it easier to turn off the green fan for the winter. (The green fan is controlled by the thermostat)