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Everything seems to work, except that it doesn't throw out cold air...more like 72-75* with vent open, and slightly colder with recirculation. I checked the manual, and apparently, with high humidity and high temps (85*, 80% humidity), I should be getting about 70* temps. Can this be right?

The deterioration of the temperature has been slow over the years, and now the car really doesn't cool down during the 30 minute drive home. I'm going to take it to a mechanic for diagnostic on Saturday. Any thoughts?

I'm clueless about A/C systems. Fortunately, it is R134.
 

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Usually you'll get a bout a 20 degree differential across the evaporator. So with 100 degree air going in, you'll get about 80 degrees out. You see, it'll take awhile for the temp to drop.

But I wouldn't be suprised if you're low on a charge. Remember physics, a drop in pressure will result in a drop of temperature across the metering device. So if you're low on a charge, you won't have a big pressure drop across the metering device, therefor, not a big drop in temp.

Usually you'll loose the charge at fittings, look for oil and dirt accumulation. BTW, just buy a stinking can of the stuff and add it untill the suction side starts to sweat. (big hose).


BTW, Randy, read a good book last week, I'm sure you've read it, "Blind man's bluff".
 

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My old Accord (91 with 212K miles) did the same thing. After a recharge (R12) it was as good as new. So far, that's the only expense outside of tires, front brake pads and oil changes. They really are good dependable cars.
 

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Make sure the compressor is cycling... In most cases (not all), a thermostat located on the evaporator will turn the compressor off so the condensate can melt and run off the evaporator coils... Proper operating systems seem to cycle about every 30 seconds.

Low charge will fast cycle.... on, off, on, off...

I disagree about 70 degrees from the registers... Should be 42-50 degrees.
 
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