A general question, if I may. Pure curiosity, IOW.

How does a typical car's a/c get rid of the heat being pumped out
of the passenger compartment? Does it have its own radiator? Or
does it share the main one?

And is there such a thing as a "typical car's a/c"?
--
Andrew Stephenson

On Sun, 04 Feb 2007 12:48:25 +0000, Andrew Stephenson wrote:

> A general question, if I may. Pure curiosity, IOW.
>
> How does a typical car's a/c get rid of the heat being pumped out of the
> passenger compartment? Does it have its own radiator? Or does it share
> the main one?
>
> And is there such a thing as a "typical car's a/c"?


If you look in front of the car, you'll see one radiator on the inside of
the radiator support, and one on the outside. The one on the outside is
the AC Condensor, the 'radiator' for the AC system.

And, as far as being 'typical', they are all typical. You have a
condensor, a compressor, a receiver/dryer and then the heat exchanger
that draws the hot air out of the car.

"Andrew Stephenson" <ames@deltrak.demon.co.uk> wrote in message
news:1170593305snz@deltrak.demon.co.uk...
>A general question, if I may. Pure curiosity, IOW.
>
> How does a typical car's a/c get rid of the heat being pumped out
> of the passenger compartment? Does it have its own radiator? Or
> does it share the main one?
>
> And is there such a thing as a "typical car's a/c"?
> --
> Andrew Stephenson
>

AFAIK, all automotive AC systems work pretty much the same way, with a
condenser, compressor, evaporator, and expansion valve. There are
differences in controls, i.e., manual and automatic, with dampers mixing hot
and cool air or moving temperature control valves to regulate temperature
and moving dampers to control where the cool air enters the passenger
compartment.

Basically, the compressor pumps liquid refrigerant to the expansion valve,
which sprays the refrigerant into the evaporator. The refrigerant
evaporates and cools as it changes from a liquid state to a gaseous state.
Hot air from the passenger compartment moves past the evaporator and the
refrigerant absorbs the heat from the air. The hot gaseous refrigerant goes
to the condenser, where outside air cools and condenses the gas back to a
liquid state, where it goes to the compressor to start the cycle again.
--

Ray O
(correct punctuation to reply)

Thank you, Hachi and Ray. I gather the a/c will usually have its
own mini-radiator. Combining it with the engine's would prove an
inconvenient engineering puzzle, I suppose.
--
Andrew Stephenson

"Andrew Stephenson" <ames@deltrak.demon.co.uk> wrote in message
news:1170613674snz@deltrak.demon.co.uk...
> Thank you, Hachi and Ray. I gather the a/c will usually have its
> own mini-radiator. Combining it with the engine's would prove an
> inconvenient engineering puzzle, I suppose.
> --
> Andrew Stephenson
>

There are a few reasons why combining the AC condenser with the vehicle's
radiator is impractical. A big reason is size - a combination unit probably
would not have sufficient surface area to get rid of heat. Another is that
the dissimilar contents would make a combo unit more expensive to make, and
radiators tend to need more frequent replacement than condensers so separate
units would be less costly to replace.
--

Ray O
(correct punctuation to reply)

It has its own. The A/C radiator is located immediately forward of the
engine's radiator.




"Andrew Stephenson" <ames@deltrak.demon.co.uk> wrote in message
news:1170593305snz@deltrak.demon.co.uk...
>A general question, if I may. Pure curiosity, IOW.
>
> How does a typical car's a/c get rid of the heat being pumped out
> of the passenger compartment? Does it have its own radiator? Or
> does it share the main one?
>
> And is there such a thing as a "typical car's a/c"?
> --
> Andrew Stephenson
>

"Ray O" <rokigawaATtristarassociatesDOTcom> wrote in message
news:83e57$45c62b42$47c2b532$14853@msgid.meganewss ervers.com...
>
> "Andrew Stephenson" <ames@deltrak.demon.co.uk> wrote in message
> news:1170613674snz@deltrak.demon.co.uk...
>> Thank you, Hachi and Ray. I gather the a/c will usually have its
>> own mini-radiator. Combining it with the engine's would prove an
>> inconvenient engineering puzzle, I suppose.
>> --
>> Andrew Stephenson
>>
>
> There are a few reasons why combining the AC condenser with the vehicle's
> radiator is impractical. A big reason is size - a combination unit
> probably would not have sufficient surface area to get rid of heat.
> Another is that the dissimilar contents would make a combo unit more
> expensive to make, and radiators tend to need more frequent replacement
> than condensers so separate units would be less costly to replace.
> --
>
> Ray O
> (correct punctuation to reply)


What Ray said.

If there were a single radiator to serve both the engine andthe A/C system,
the physical size of such a unit would exceed the space available. They
_could_ make a single radiator that was double-deep, but then repairs would
become more costly because the engine's radiator is prone to more failure
than the A/C radiator, but if there were a single unit, then the A/C would
require service any time the engine radiator failed. With the arrangement of
parts as they are today, one can replace the engine radiator and leave the
A/C system intact.

Damn, that's what Ray said ...

Thank you also, Jeff. Sticking to standard parts has to be a
powerful argument. That way, besides the cost savings, there
is also freedom to fit the a/c unit in a variety of vehicles.

Oh hum, idle curiosity, as I said. <g> (I shall save the one
about using standardised fuel.)
--
Andrew Stephenson

On Sun, 04 Feb 2007 19:32:28 GMT, ames@deltrak.demon.co.uk (Andrew
Stephenson) wrote:

>Thank you also, Jeff. Sticking to standard parts has to be a
>powerful argument. That way, besides the cost savings, there
>is also freedom to fit the a/c unit in a variety of vehicles.

Yup. They make common components that can go in many different
cars, like the AC compressors, magnetic clutches, evaporator and
condenser coils, receiver/driers, etc., and they get the benefit of
mass production on those parts.

Plus having common parts makes it simpler on the Parts Department,
since they only need to stock two or three compressors to cover most
of the cars. A "small" compressor for most cars and pickups, and a
"large" for the SUV's and Vans with dual air conditioning.

(Oh, and now there's one set of compressors hoses and parts with the
PAG or POE synthetic refrigeration oil and the right synthetic rubber
seals for newer R-134 cars, and a set with different seals and Mineral
Oil for R-12 use. In another twenty years they won't have to worry
about that.)

The brackets for compressor to engine, mounting tabs for the
condenser to the radiator support, the heater box to fit in the
under-dash space in that car, the refrigerant lines and hoses - those
are the parts custom-made to fit in a certain car model. But even
then, they can design all the small sedans on that platform to use the
same basic parts.

>Oh hum, idle curiosity, as I said. <g> (I shall save the one
>about using standardised fuel.)

There are many standardized fuels out there, it's just two big
problems that form a "Chicken or Egg, Which came first?" paradox - Car
Mass Production and getting the fuels and the fueling systems deployed
to be widely available.

Car Technology, teaching a fuel injection computer to deal with a
totally different fuel (either singly or Dual-Fuel with Gasoline, or
Flexible Fuel to handle varying Methanol/Ethanol blends with Gasoline)
would be trivial at the Mass Production stage. All you need to do is
add another set of injectors, and teach the computer how to switch
back and forth and the running qualities of the other fuel. A few
years of intensive research, and I could build a car that would
automatically switch over between fuel sources (to Gasoline when the
CNG tank runs out) with nary a hiccup...

But doing one-off end-user fuel conversions is a rather difficult
PITA, especially if you want Dual-Fuel for Gasoline or Diesel
compatibility depending on the base engine tech used.

In article <evrcs21a7atdu3flmfku75dp4vmjjgfjko@4ax.com>
blnospambergman@earthlink.invalid "Bruce L. Bergman" writes:

> On Sun, 04 Feb 2007 19:32:28 GMT, ames@deltrak.demon.co.uk (Andrew
> Stephenson) wrote:
>
> >Oh hum, idle curiosity, as I said. <g> (I shall save the one
> >about using standardised fuel.)
>
> There are many standardized fuels out there, [...]

Um... I _was_ joking about the "standardised fuel". OTOH, your
answer proved interesting. Ta. :-)
--
Andrew Stephenson