texasridr

Putting a thermometer inside my a/c vent, my air only goes down to 40F. This is on the recirculate setting, driving for at least 20 minutes (commuting). It doesn't seem to matter whether the temp outside is 100+ or only 80, it won't go under 40.

I think my air used to be colder, but I never measured it. I had the system checked by a mechanic shop and they said it is functioning fine and the refrigerant level is normal.

How cold should I expect the air to get coming out of the vent?

GEORGE_JET

It is functioning fine, if the temp was any lower the condensate would freeze onto the evaporator instead of draining out. The evap would be a large ball of ice in not time at all, and then of course you would not get any cold air out of the vent.

GS4_Fiend

iTrader: (22)

What else you want? 40 degrees F for R-134A is the coldest it can get. That's perfectly fine operating system.

I just learned something new from George_Jet.

texasridr

I want that "artic" air I used to get. It was often too cold on the lowest setting and I would bump up the temp setting to the 70's to be just right. Since I never measured it before, I don't have any evidence that it can do better. I sure feels different though...

GEORGE_JET

I don't really know what you mean by ARTIC air. Water freezes at 32 deg. In order for you to get 40 deg air out of the vent, the evap must be a little colder than 40 deg.
If the outlet air was any colder, I would suspect the the evap temp sensor was bad.

It does not matter what type of refrigerant you use R12, R134a, R22, R410.
You also live in TX, you must have seen the stream on condensate pooling under you car on a muggy day. If your evap got any colder, you would be extremely unhappy when it freezed up into a ball of ice.

Now keep in mind, these cars are designed to be operated at different altitudes, IE Colorado Springs 6200ft. Water freezes at even higher temp ( around 34 deg I believe ). So they cannot design the evap to run at those temp, Even though the refrigerant is more than able to cool much lower, such as your typical home freezer ( same type refrigeration system, but it does not have to deal with the volume of humidity that you have in the car).

ES3_Ray

coldest ive ever measured my air is around 37-38 degrees from the center vent, thermometer inside

i gotta recharge my system soon actually, it gets hot when the rpm is low.

texasridr

Thanks for the info guys. I've resolved that the higher outside temps is the only issue here.