I see the same thing on the rentals, Dave. The vehicle cools off in the Atlanta sun rather quickly. But, I don't get the sense that the vent temps are all that low.......I don't feel that they are below 45° or so........I'm wondering if you notice the same thing.

If so, then the insulation and the window tint must be a significant factor in the performance of the a/c..........rather than the cooling system itself.

Thanks for the replys. The system was reworkrd this year, new compessor and drier, flushed, pressure check, R134, On low fan speed 40 degrees, on high fan speed 55- 60 degrees. I am wondering if the evaporator could be clogged so that air is not circulating as well. I am heading out to work on it right now. I will post any success or surprizes when I get done!

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If it ain't broke take it apart and find out why.

1983 300SD, 4 speed
1994 C280
1987 300TD wagon
1996 HD Road King

Ride in Peace Eric Peterson, Harley of Macon

To those who asked, yes cleaning the evap. helped alot. Just the sight of the black yuk coming out from under the car when flushing showed how dirty it was. I also tinted the windows with 25% tint. Still can see the mirrors at night and major difference with interior temps. Thanks Mike

Vent temps can't be any lower that 38-41 degrees. I figure the diffence is volume of air movement. In the MD80 I can turn on one AC pack and the supply temp to the cabin is 40 degrees. The aircraft does not cool very well here in Texas. If I turn on both AC packs, The aircraft cools a lot better due to the increase in airflow. Not temperature change. I think the new cars have a higher airflow at the normal AC temps of 38-41 degrees.

Also I notice a big differnce between the 240D and the 300TD. The wagon
has so much more volume to be cooled than the sedan. I feel the movement of hot air from the back of the car while driving.

Dave

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1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car