How quickly do cars AC begin effectively cooling? (vehicle, air conditioning, truck)

[choo_choo_train_lol]

Odd question but am wondering about autos made in the last 15 years, how hot they are after say 1 minute or 5 minutes on a hot sunny day. Like Southern United States summer day. I was told by someone who has lived in Texas that the interior of your car will stay hot for +10 minutes after turning it on... that the AC can't quickly cool down a car that has been baking in the sun.

I wonder this about the comfort of living in a place like Houston or Atlanta. Does your vehicle stay +90F until you're halfway home from work? Or does the AC make things comfortable within a minute or two of turning on the car?

I feel really stupid for asking this. There are plenty of hot summer days where I live, but nothing like the South, and this winter has gone on for so long that I don't remember what summer is like. (lol) Most of my life I've owned vehicles without AC and hated driving on hot days. Any answers replied will have a significant impact in choosing what part of the USA to relocate to in the future!

[jambo101]

If the outside temps are in the 90s with windows rolled up interior car temps could easily be 130+, your air conditioning will take several minutes to cool the car down, you can help a bit by lowering a window or two and put your vents on recirculate..

[Ed_RDNC]

This is actually several, related questions.

1) How long before a standard car's typical A/C will start to cool your car? The discharge air temperature should start dropping immediately, and after about a minute it should be cool (the A/C has cooled off itself and is now starting on the cabin air). After two minutes the discharge air should be very cold, (car A/Cs cool the discharge air to a MUCH colder temperature than systems for your home or office).

2) How long before a standard car's typical A/C cool your car to where it's comfortable?
If it's really hot and sunny outside, then the inside metal and plastic and such have a thermal mass that will become hot to very hot. After the A/C cools down the cabin air, it then has to start on the interior itself. And it's working against the sun's heat that continues to come in. My experience is that getting comfortable enough to need to slow down the fan will take at least 10 minutes, and (with the A/C was working as it should), even up to 20 minutes.

As the previous poster noted, if the cabin filled with extra hot air, (and presuming it's hotter than the outside due to heating from the sun), then rolling down the windows a bit to get some not-so-hot outside air as replacement, for 2-3 minutes, might be a good move.

This last experience (the 20 minutes till comfortable) prompted me to recognize that I live in the sunny south and have a black interior. So I got the IR-reflective window tint/film, and it made a VAST difference. Now even if I leave my car in the hot sun on a hot day, my interior never gets more than slightly-warm. Before it was "hand cloths on the steering wheel or get burnt", and afterwards I could jump in, firmly grab a-hold, drive away and I'd turn down the fan after 2 blocks. That tint is amazing!

[NHDave]

Originally Posted by jambo101

If the outside temps are in the 90s with windows rolled up interior car temps could easily be 130+, your air conditioning will take several minutes to cool the car down, you can help a bit by lowering a window or two and put your vents on recirculate..

I've always questions that recirc recommendation. If you do that then the AC has to cool 130 degree air instead of outside 90 degree air. I leave mine on fresh air and lower the windows a bit.

[need4speed2012]

It all depends on the size of the vehicle !!!

[jambo101]

Originally Posted by NHDave

I've always questions that recirc recommendation. If you do that then the AC has to cool 130 degree air instead of outside 90 degree air. I leave mine on fresh air and lower the windows a bit.

I'm thinking you need to evacuate the very hot air in the car at least for the first few minutes then you can roll up the windows and switch from recirculate.....ooops just realized i got it backwards Recirculate after the car has cooled down and fresh air setting to start the cooling process..

[NHDave]

Originally Posted by jambo101

Recirculate after the car has cooled down and fresh air setting to start the cooling process..

That sounds better

[cdelena]

A big factor is solar heating of the AC evaporator on the front of the car. If the front has been baked with sun exposure it will cool slower than a car where the front has been shaded.

[NHDave]

Originally Posted by cdelena

A big factor is solar heating of the AC evaporator on the front of the car. If the front has been baked with sun exposure it will cool slower than a car where the front has been shaded.

Same thing applies to a home window A/C unit, always put it in window that gets minimal sun if possible.

[vmaxnc]

Originally Posted by jambo101

I'm thinking you need to evacuate the very hot air in the car at least for the first few minutes then you can roll up the windows and switch from recirculate.....ooops just realized i got it backwards Recirculate after the car has cooled down and fresh air setting to start the cooling process..

This^^.

When I've owned 4 door cars I would roll the rear windows down when I first got in. That would drop the internal temp 20, 30, 40 degrees in a couple minutes. It also creates a bit of a vacuum to pull the cold air through the vents and out the rear windows. It's not as effective in my truck or coupe, but it still helps. Gotta get that hot air out.

My 19 year old pickup takes several minutes before it really starts to cool. My GTO takes about a minute. Then it's a matter of getting all the interior pieces to release their heat.