Does red and blue make...purple?
July 11, 2010 11:21 AM Subscribe
Does changing the "temperature" setting on my car's manually controlled AC just waste energy?
posted by razdrez to travel & transportation (11 answers total) 1 user marked this as a favorite
I have a Hyundai Elantra without climate control--meaning I can't just set a temperature and it automatically adjust to maintain that temp. All I have is a dial that goes from cold to hot. Or more precisely, from blue to red.
Now, my thinking is that at the max heat setting, it's blowing in hot air from the engine. The max cold setting is pure AC. But if I dial in a setting that's in the middle of those too, what is happening?
Is it making the AC less cold? My guess is that ACs have one setting: ON, so regulating temperature is done by turning it off in intervals, meaning this doesn't happen.
Or do you think that even with the cheaper AC units, it's still doing an on/off cycle to maintain a level of cooling that I dialed in?
Or, is it really just mixing in warm air from the engine (or outside) to temper the cold air? In this case, using any setting other than max cool is basically warming up the cold air to make it something more comfortable--or just wasting energy.
I've always wondered this but don't know much about cheap car temperature controls.