jerryc41 wrote:
When you want the most from your car's air conditioner, you set it to Recirculate. Wouldn't the same thing work with the car's heater? Instead of heating the 20° air from outside to 70°, the heater would be maintaining the 70° air inside the car. Of, course, you could switch it to Fresh Air occasionally.
That's what I do cuz that's what its there for.