Why does a car get worse mileage when the AC is on recircutlate versus outside air?

Question

Just question that has been bugging me. You would think it takes less fuel to cool already cold air than to cool hot air from outside?

Answer 1

Outside air is hotter and more humid. Cooled inside air will take less energy to keep cool. Latent heat seats plastic and parts inside the car cool down and each hour they keep getting less and less hot. Car air conditioners are larger than most window units so they take a lot of engine energy to run. Some people say wind resistance of both windows open vs. closed windows and A/C on. Fact is it takes about 5 hp to keep a car at 60 miles an hour and it takes an additional 4 hp to run the compressor for the A/C.
Tips to equal the drag of the compressor use synthetic oils engine and transmission drive like there is an egg between your right foot and accelerator pedal. Keep the car clean and waxed air up the tires to the pressures in the owners manual and if the car gets better gas mileage with MID GRADE or PREMIUM fuel. Measure the difference and cost use the most practical fuel.

Answer 2

It doesn't. Having the A/C on uses very little fuel because the load on the engine is not that great. The minor load does not change based on where the A/C is getting air from.

Answer 3

your query is flawed; it does not burn more gas to recirculate air as opposed to outside air. when the compressor is on, there is a drag on the engine and you will use more fuel. where you get the air from the blow against the coil is not a factor.

Answer 4

on the highway you should get better gas milage,but in stop and go traffic and on city street with the ac on you will burn more gas.(THE RECIRCULATER MIGHT SEEM LIKE IT IS BURNING MORE GASS,BUT IT IS NOT)

Answer 5

ac definitely. when you open your windows for air it creates drag and worsens gas mileage and speed.