What Determines Air Coldness?
 

I have a general air conditioning question somewhat unrelated to my 2000
Jeep Cherokee. What determines how cold an air conditioner will blow? Mine
blows cold, but on the same day, a friend's (not a Jeep) blows colder. Is
maintenance a factor? That is, if it's working correctly, meaning it's
blowing cold, would maintenance be a factor in it blowing *colder*. Or is
this just a matter of different manufacturer's equipment working
differently.

Re: What Determines Air Coldness?
 

Complex question & answer. I hope you get better answers than mine, but I'll
give it a shot!

Variables affecting perception/reality of cooling:

Maintenance (lots of individual variables therein)
Refrigerant (R12 vs 134)
Interior volume of vehicle
Initial interior temperature of vehicle
Recirc vs fresh air setting
etc., etc.

Back in '71 the techs at the Esso/Exxon station where I worked (changed names
mid-summer) would put a dial-type thermometer in dash outlet--if it got down to
40 degrees F, it was good to go! Try measuring for objective difference.

YMMV, greatly!

Paul B.
01 XJ
http://scienceteacher.biz/General/JEEPphotos/index.htm

Re: What Determines Air Coldness?
 

The gauge on the manifold (the one with the hoses that go from the refridg
tank to the high/low side of your AC) has a temperature that coincides with
a pressure - different pressures for different temperatures for different
refrigerants (i.e.: R-12 = 30deg F @ 28.5psig - R134A = 30deg F @26.1psig)
this temperature is somewhere in the center of the evaporator. whatever is
between somewhere in the center of the evaporator & the end of your
thermometer will probably be the largest variable.

http://www.delanet.com/~pparish/ac_works.htm

--
Carlo F. Serusa, Jr. RPh
carlo.jr@comcast.net
'98 Sahara TJ - '89 YJ - '79 Scout II
O|||||||O
'92 Explorer '65 Mustang


"PLB49" <plb49@aol.com> wrote in message
news:20030818231249.29802.00000164@mb-m24.aol.com...
> Complex question & answer. I hope you get better answers than mine, but
I'll
> give it a shot!
>
> Variables affecting perception/reality of cooling:
>
> Maintenance (lots of individual variables therein)
> Refrigerant (R12 vs 134)
> Interior volume of vehicle
> Initial interior temperature of vehicle
> Recirc vs fresh air setting
> etc., etc.
>
> Back in '71 the techs at the Esso/Exxon station where I worked (changed
names
> mid-summer) would put a dial-type thermometer in dash outlet--if it got
down to
> 40 degrees F, it was good to go! Try measuring for objective difference.
>
> YMMV, greatly!
>
> Paul B.
> 01 XJ
> http://scienceteacher.biz/General/JEEPphotos/index.htm
>
>