running the heater

we all know that running the AC burns more gas, is it also true for the heater ?

guvy

I've never really noticed a major difference in gas mileage when using the heater. If you were going to get exact it probably does use a bit more. Unlike the heater, the AC uses more power since it has to "condition" the air. From what I've been told this happens by using an additional pump. Maybe there is a mechanic out there that can be more exact.

No, running your heater doesn't hurt your gas mileage. The AC compressor runs off your belts, Heater is more or less just hot air from your engine.. Actually, if anything running your heater is good for you car, keeps it from over heating..

- Miker

In case you guys care:
Running the heater involves circulating hot water from the engine. It is passed through a small "radiator", like the one under the hood. The higher the heat setting on your controls, the more of the air that is passed through the fins of this radiator into the interior of your car. So theoretically, it can help in cooling the engine as well, but not by much.
Running the A/C involves a similar system, but the air passes through fins cooled by charged freon instead of hot engine water. To get this freon that cold, it is run by a compressor, that is turned by a belt in the engine. This is where the power is robbed, when the engine must work to turn this compressor. When the A/C is not in use, the belt simply spins the pulley, with no really noticable power loss, but when you turn on the A/C, it connects that pulley to the compressor, and takes power to run it.
In other words, a really long boring explanation of why A/C robs engine power and heat doesn't.

If you run your defroster, it will draw some from the engine. It turns the compressor in the A/C that helps reduce fog(moisture) on the windshield. Also, running your A/C WILL NOT make your car overheat. It makes the engine run hotter, but your T-Stat recognizes this and engages the fan to cool down the motor. And plus, have you ever seriously thought of running the heat in the summer because you thought the car was gonna overheat?? what about yourself?? I did it once in Arizona coming down through Apache Junction from the Rim in a Jeep that I thought was gonna die. Well, I ran the heat, to reduce strain, but it was way to ****** hot. So I ran the A/C instead. We made it down, no problem. If that isn't a test for what I'm saying, than you tell me what is. wha