Auto Temperature Control

Our previous Civic was like that. With our 2010, Canadian build Prius however: if AC is currently off and I push Auto, the AC button light continues to stay off. And using ScanGuage for a while to monitor AC, it definitiely was off. Anyway, might depend on the year and the country, and generation?

What I would do with the Civic, and probably would work for you: push Auto, and immediately push off on the AC button.

 

I've read that it's actually good to run your AC with your defrost...removes moisture, and also good to keep the AC system working even in the winter.
I think it's activation is actually by chosen design.

 

Monitoring with ScanGuage I found if the AC light is on, the AC compressor is running (at a variety of wattages) about 50% of the time. Typically on and off for 30 seconds to a minute. It never takes an extended hiatus.

 

You can turn this off in the settings.

 

Yeah occasional AC use is more or less necessity, to keep oil circulated, prevent seals from drying out. This is what I've read, by no means that up on the hows and whys. I just keep it in mind, kinda like our ink jet photo printer: better run it every so often.

 

Are you using Toyota's definition of A/C, ie: any using of the heating/ventilating system, not just the Freon-type Compressor, active cooling system? This muddies the waters in the Owner's Manual, for sure. North Americans at least when they say AC mean the Freonish system.

Anyway, on our Canadian 2010: if I've turned AC button off and hit Auto, AC (Freon type) does not run. The one time AC will run with AC button unlit is occasionally, if I've set mode to Heat/Defog. Again, monitoring with ScanGuage.

 

Well with my new vehicle, I'm basically the climate control system-no computerized control...and I run the AC with the defrost, and run the AC in winter for the very reasons you site.
One of those knowledge things of which I can't even remember where and when I heard this advice. It's now become standard operating procedure.

 

Yes. I perceive AC in a car as a feature that cools the interior on a hot day. So now it's cold in London, and I want some heat (auto or otherwise), I tap the AC button off, as I also perceive that using AC increases fuel consumption.

However, the car's interior mists up, especially the rear windscreen and rear side windows, so I may switch the AC button back on, based upon the posts in this thread. Thanks!

 

Excellent. I tapped the AC switch so that it was on today, and mist free windows. Cheers!

 

I guess the air conditioner is on, like all other cars. Just to remove moister. I turn it off. Even with it off it does run when push the defrost button.

 

I used Carista to disable the Auto button from activating the A/C. There may be another way to do this. You can search these threads for more information about Carista.

 

You do not have to worry about under-using the AC with the Prius. It has an electric motor that is sealed inside the system. On most other cars, the ac is run by a belt and pulley, which means that the rotating shaft must go into the compressor and it's the seals around that shaft that go bad.

 

One other observation. The new Prius heats up a bit slower than my old one. Also when you hit the front defrost, the fan speed is still controlled by the engine temperature. So you may need more fan speed to clear the windows. I assume you maybe able to manually adjust the fan.