Prius Air Conditiner Management

<div class='quotetop'>QUOTE(TonyPSchaefer @ Jun 22 2006, 10:34 AM) [snapback]275326[/snapback]</div>

He was using the ice water and tubing to cool his SKIN, not the car.

 

<div class='quotetop'>QUOTE(brighamwj @ Jun 22 2006, 09:13 PM) [snapback]275638[/snapback]</div>

If you only have 300 miles, it sounds like you do very short trips and have the air in a portion of that?

Take a nice road trip or at least go over 70 miles or so and you should see a dramatic difference!...

You should get 43-44 with the Air running almost all the time "if" you are doing long trips on the freeway.

Turn the air off and that should go to 48 - 50+... even at speeds of 70 - 80 mph.

The Air Cond on high pulls a fair amount of juice.

If you engage the "Auto" button some feel you get worse gas mileage, and I agree in cooler climates it practically unecessary to ever use.
But down where its really hot and you first get in your car and its 120 - 140 degrees, you can roll your windows down for about 30 seconds to get the blunt of the hot out, then make sure the "auto" button is engaged.
That will cause it to blow much harder to get you and your passengers cooler much faster and then it will tone things down once you get the cabin temp cooler.

The final effect gained is that it doesn't blow full blast all the time as you will only get comfortable to the extreme cold and never save too much gas.

If left to our own comfort vices, we will let the cabin temp in our car be much colder than we would in our house!
We actually get used to the colder temp, especially when its hot out as its a nice balance!


Have you ever noticed that many like to run thier ambient air temp in thier homes much colder in the summer than they like it in the winter?.....
We are funny creatures that err to the side of security and comfort and it doesn't always make practicle sense.

The Auto button is a good thing if you set your temp and a reasonable spot that works for you.... if you keep your temp set to "low" all the time it may use more gas than needed.

I'm not so broke that I'm going to sweat and be miseable and advertise to all my passengers in my prius how fragile and pitiful the prius is by freaking out over not being comfortable to save a few pennys and forcing them to hate the ride.

Unless you do the same in your home and all your other cars.. why torture yourself in the prius?... because we have a gauge and its a game to see how high of a mpg we can get?...
We can become entraped and captured by the game of gas mileage.

If its all about gas mileage... walk or ride a bicycle and take 20 times longer to get to your destination! :lol:
Just where will you draw the line?

But your prius should get much better gas mileage once you get out on the open road a little more.

It actually "wastes" power during the first 10 miles or so of your travel getting and keeping the engine warm and initially cooling down "or heating" your cabin temp... once your on the open road, all that balances out and its easy to maintain with lesser energy and gas.

 

<div class='quotetop'>QUOTE(dagerlach @ Jun 23 2006, 09:43 AM) [snapback]275847[/snapback]</div>

So if the electrically driven compressor is "less" efficient and the fuel consumption is 19% "better" then does it not blow as cool?

If it uses less gas, yet is less efficient too.. what am i missing Here?

 

<div class='quotetop'>QUOTE(dagerlach @ Jun 23 2006, 12:44 PM) [snapback]275957[/snapback]</div>

Well I guess why I was wondering is that I have a grand cherekee and when the air is on high and recirculate, its really really cold!... I have boosted the freon in it a couple of years ago to make sure its full and it seemed to make it colder.

The prius although is totally sufficient and does the job just fine, it seems it not quite as frigid cold as my jeep?
I was wondering if thats just the nature of the beast and there is nothing I can do about it, or whether I should try to boost the freon level in it too?
Its brand new, but maybe they only bring the charge up to low nominal at the factory to preserve compressor life?

 

Hey guys,

here in AZ "Auto A/C" is a killer for MPG, at least for me: I've seen up to 10 MPG reduction. It happened to me. Not once. When I was using the Auto mode, I could barerly get my MPG above 50, whith manually controlling it I am constantly getting at least 57. So, assuming 5 MPG reduction is improbable is wrong, "Auto AC" could very easily tank your MPG by twice as much.
The best solution for me was to roll windows down for the first 3-5 minutes of my commute from work (3:30 PM - the hottest portion of a day - always above 110 on MFD, 99% of thime not a cloud in the sky and no covered parking), then set temp at 80 and fan speed to one below the middle with vents blowing at me. In about 10-15 minutes I could comfortably change the fan speed to the one up from the minimum. I still see about 2-4 MPG reduction but as many pointed out already - my comfort is well worth it.
Windshield sunshade helps alot.

 

<div class='quotetop'>QUOTE(CrazyRussian @ Jun 23 2006, 01:15 PM) [snapback]275966[/snapback]</div>

Wow...thats hot enough!....

If you had the temp set very low at all, it will be trying to attain that setting. 80 seems reasonable,... maybe the auto only works best for certain climates...

Anyway... I used to not use auto at all when I lived in Washington state, of course I rarely had the air on too!!!

But here in texas If I don't run the auto... many times the air will just blow so so.. even with the fan on high, its not until I hit the auto that it blows hard like it should, and while on auto, once it gets down to my preset temp, it slows the fan speeds automatically to accomodate.

If you are in that hot of an area and your commutes are relatively short, you may have better results doing it manually because your temp barely has time to get down to settings before you reach your destination?

I'm only guessing of course since I don't know your commute... and I'm not an expert... only going by my observations.

 

<div class='quotetop'>QUOTE(windstrings @ Jun 23 2006, 01:25 PM) [snapback]275969[/snapback]</div>

My commute is about 25 miles each way ... 80 feels comfortable when it's over 110 outside with the sun always in your face like an interrogation light ...

but, as Arizonans say....it's a dry heat .... so we bake

 

All this is a pretty personal decision, I'm sure your average 25 MPG car gets under 20 with the A/C on full blast in Phoenix too... In any car it's a give and take, comfort vs. efficiency.

 

<div class='quotetop'>QUOTE(SCDrJ @ Jun 23 2006, 01:59 PM) [snapback]275987[/snapback]</div>

maybe not so bad an impact on a car that only gets 25mpg....
when a car is efficeint enough that it gets 50mpg, the impact of having air on will be more dramatic.

To exaggerate for the sake of understanding.... if the prius was efficient enough that it could milk 100 miles out of a gallon of gas, the Air conditioner would probrably make a dent of up to 10 or even 20 mpg.

Remember the Air takes the same amout of gas whether the rest of the car is doing well on gas or not.

Our only salvation is that the electric air appears to be a bit more efficient.

 

While reading the manual for my old minivan (vehicle immediately prior to my Prius), it recommended opening the back windows (vents) and driving with the A/C on and in Fresh Air mode for a few minutes before closing the vents and changing to Recirculation mode.

My impression was that in Recirc mode, the cabin air (which is at a significantly higher temperature than the outside air if it has been sitting in the sun) is the air being recycled and having to be cooled. It's easier (and quicker) to cool 110 degree air (the outside temperature) than to cool the 130+ degree air (the temperature inside a sitting vehicle).

So, I would assume that rolling down the windows and purging the stagnant (and Extremely hot) air and replacing it with only 'mostly hot' air would help the A/C cool the vehicle a bit more quickly.

Or am I completely off base here?

 

If I remember correctly, opening the windows to let out the hot air is actually recommended in the prius manual.

And to the poster that said something about getting gas at 3AM..
The colder the temperature you pump gas at, the more 'dense' it is... Granted it's not really very significant... But to be really technical about it, You WILL get more gas for your money when it's colder...

 

<div class='quotetop'>QUOTE(Anubis @ Jun 24 2006, 12:56 AM) [snapback]276241[/snapback]</div>

sounds right to me... I notice the outside air is cooler if its extremely hot in the car, but only in a matter of minutes, the ricirc air is better... I hate to mess with it all the time.. so I just let Auto take control and I set the temp to where I want it on the steering wheel and the fan speed, recirc etc is all taken care of without me having to stress over it.

 

<div class='quotetop'>QUOTE(dagerlach @ Jun 26 2006, 06:18 AM) [snapback]276772[/snapback]</div>

The tactics seem to be different for different part of the country.

When I lived in Washington state, I seldom used auto "ever", but when your in a hot area, the auto seems to be the most troublefree and I really don't see a mph impact over monkeying with it all the time.

I'm getting about 45mpg staying about 70 - 72 degrees inside cabin temp when its 93 - 102 outside, and I drive 70 - 80mph quite frequently in an area with gentle rolling hills to flat.

 

<div class='quotetop'>QUOTE(Wildkow @ Jun 23 2006, 01:19 AM) [snapback]275702[/snapback]</div>

LOL

At least with an EV, you can sneak up on the critters**. I guess one could keep some BBQ sauce in the cooler.

** Seriously, you really have to be careful **