What burns more gas in your car Heat or AC?

Question

What burns more gas in your car Heat or AC?

Answer 1

the heat is generated by the heat from the engine. That is why it takes a few minutes for the heat to work, it takes until the engine is warm for it to come out.

The heat is always there, it's just a matter of turning on the fan that blows it into the passenger area.

For A/C, you need to turn on an A/C compressor which turns via a fan belt off your engine. If the A/C is turned off, the wheel(pulley) on the A/C compressor free wheels (no drag), turn the A/C on and the compressor engages and creates drag on the engine - burning more gas.

Answer 2

As most people have said, it's the A/C.

The heat is very easy to make because the engine becomes very hot within a few minutes of starting the car. In fact most engines have an elaborate series of fans, radiators, and fluid filled pipes to keep the engine from overheating. So simply taking some of that heat that already exists and blowing it into the cabin is no big deal at all.

The air conditioning is another story though. The A/C takes a significant amount of electric to run what is basically a small refrigeration unit. In turn more energy is taken to replace the electric that has been used, and that in turn leads to a lower fuel consumption.

But at the end of the day the difference is hardly significant. Some people like to open windows, thinking they are saving on gas. But the reality is that by opening the windows they are significantly increasing the drag of the car, that costs gas.

If you never switched on the fan, the A/C, the radio, or operated any electronic gadget in the car except the absolute essentials, you would save on gas. Would that saving be significant? Probably not. Would it be worth the sacrifice in comfort? Almost certainly not.

Answer 3

Gas For Ac

Answer 4

When it is really cold outside there is no fluid circulating through your radiator at all when your car is first started. As the engine heats up, your heater core contains the only fluid being circulated through the system. This is an attempt at creature comfort. Get the passengers warm first, worry about the engine later. To compensate and to heat up the engine quicker into normal operating range, more gas is made available. This also allows it to run more smoothly. You may also notice that your car has more power when it isn't fully warmed up yet. During this warm-up period your fuel economy is much worse. I'm not going to say that it is as bad as running the A/C but it is probably close. If you are running the heater and the engine never reaches full temperature you may never leave this heat-up phase and cause significantly worse gas mileage. This is probably most evident when making short winter trips instead of long highway trips.

This may be where the question was actually coming from.

Warming your car up before you leave your home may also give the perception of worse gas mileage during the winter.

Answer 5

I dont drive but People have always complained more about the AC burning gas alot faster then the Heat does

Answer 6

First, any time you turn on ANY accessory, the radio, fans, lights, or whatever, there is additional drag on the alternator, which is powering these things AND trying to keep the battery at full charge, but not enough to cost a worrisome loss of MPG.

Running the AC however, causes a LOT of drag on the engine because the AC compressor AND fan are on together.

Answer 7

The heater is only recirculating hot water that was already heated by the engine's running. The only energy is that of the little blower motor.

The A/C however has a large energy- consuming rotary unit that needs to be driven by the car engine to do the work of extracting heat.

So the A/C takes a lot of new energy.

Answer 8

AC. the only power the heat uses (since it uses the heat all ready there) is the fan. At the highest fan setting there will be some extra load on the eng. from the alternator being under more load. But the A|C compressor creates way more drag on the eng. allong with the fan load.

Answer 9

The heat gets hot by the cooling system just before the coolant gets cooled thru the radiator so it dose not burn gas. The A/C is driven by the engine and slows it down so there is less engine power so you have to step on the gas pedal to speed up, so the A/C slows down the engine causing the engine to burn more fuel.Heated seats are eletricaly powered so they don't butn gas.

Answer 10

The AC, because your engine has to turn the compressor.

Heat is just circulated fluid & a fan.

That's why you feel your power decrease when the AC kicks on.