Quote:
Originally Posted by pig4bill
It's not volts, it's amps. More specifically, power, which is volts times amps. Volts will remain somewhat constant, so the more amps, the more power. The engine running draws hardly any power, but the blower fan on the a/c does use some.
The power comes from the alternator. If it's not charging the battery when the engine is running there's something wrong with it. If you ran the engine without the alternator working and the compressor engaged, the battery would probably be dead in an hour or two. The main purpose of the battery is simply to start the engine.
And technically speaking, power is current squared times resistance. DUCY?