AC - air in vent's 28 degrees
02-03-2007, 03:06 PM
#1
Race Car
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AC - air in vent's 28 degrees
Just replaced the Compressor, RD and Expansion Valve. I checked the temp and it's going down to 27 Degrees yes 27 F. Is something wrong or is this normal?
Last edited by Randy V; 02-03-2007 at 03:23 PM.
02-03-2007, 03:55 PM
#2
Under the Lift
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The freeze switch is supposed to switch off the compressor when the temp detected at the evaporator hits 32 and back on around 38F. The switch is not adjustable. Mine seems to work at a lower point. I've measured as low as 18F out of the vents, although the compressor is cycling as if the switch is working. I've never had any problems with icing the coils, but in Florida you might due to the high humidity. I've seen a number of our cars get to the mid-20s at the vent with everything appearing to work as it should. This is using an IR gun, which may not be accurate in this situation.
02-03-2007, 04:06 PM
#3
Owns the Streets
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Freeze switch is under the flimsy plastic cowl cover at the back of the hood.
Little squarish metal box with copper pipe coming out of it.
There should be a screw on the side of the freeze switch box to adjust temp shut-off for the compressor.
Was told to adjust around 32 to keep the coils from freezing up.
Once the coils ice up, may take a while for the ice to melt off the coil. Meanwhile, you'v got no AC.
Something to consider on those balmy 90+ days driving in a 928 with windows down and sunroof open waiting for the coils to free up. Just a thought.
With the oven thermometer stuck in the center vent, I get around 30-32. But it's been a while when I got to run AC.
The pocket clip on the oven thermometer clips nicely to the center vent vanes.
Ernest (NYC)
Little squarish metal box with copper pipe coming out of it.
There should be a screw on the side of the freeze switch box to adjust temp shut-off for the compressor.
Was told to adjust around 32 to keep the coils from freezing up.
Once the coils ice up, may take a while for the ice to melt off the coil. Meanwhile, you'v got no AC.
Something to consider on those balmy 90+ days driving in a 928 with windows down and sunroof open waiting for the coils to free up. Just a thought.
With the oven thermometer stuck in the center vent, I get around 30-32. But it's been a while when I got to run AC.
The pocket clip on the oven thermometer clips nicely to the center vent vanes.
Ernest (NYC)
02-03-2007, 04:24 PM
#4
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What Bill said.
__________________
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
02-03-2007, 09:49 PM
#5
Race Director
I've also seen temps as low as 19 degrees on my R12 system....or about 50-60 less than ambient....my freeze switch does work.....of course it seems to work on those 100 degree days when the A/C has been running for a while.....then the air gets hot quick!!! But a broken recirc flap doesn't help either!