From the OP's original post:

I called V-A & they said it is simply a function of the air temp differential, and is "normal". I have never experienced this in any other A/C'd car, although they weren't black cars with aftermarket air.

Don

On the vehicle I'm dealing with the water is not coming out of the vents but dripping from the evap case like the drain isn't big enough. I have already verified the drain is clear and as mentioned am getting normal water draining with normal driving. Our humidity has been really high this year so I suppose it is possible that I'm getting so much condensation it is over flowing the drain.

Or another random Idea I just thought of.... Where is your A/C drain located? Mine just has a 1/2" aluminum tubing stub a few inches out of the firewall going down... In theory it could be possible that at highway speeds there is a high pressure area at the back of the engine bay not allowing the condensation to drain properly. I may try extending my drain down under the car where again in theory it would create suction by the air passing under the car.

True that icing of the evap would cause a degredation of the cooling from the vents which I'm not getting but the car I'm dealing with is a convertible so you are never really cooling off like a full cabin car so for me it's hard to tell if I'm loosing cooling... need to get a battery in my dash temp gauge I haven't used in 10 yrs.

I had the same problem with my VA a couple years ago on a trip from California to Goodguys Colombus. Talked to them at the show and they nodded. They said this sometimes happens in conditions where the a/c is at max for extended lengths. We ran it hard for 5 straight days.

I don't normally see it otherwise. Where we live is not humid though like back east.

Tim

Good point.

Maybe I have never had an issue because I drain out to the side cowl vent (high suction area) and always have a down hill run on the line.

Not Normal
 

69hugger,
Sorry you are having issues with your a/c system. You should be concerned; condensation dripping inside your interior is NOT normal. There are 3 reasons why this may have happen to you.

1. There is a crack or a hole in your evaporator. Water always follows the path of least resistance.
2. The hose connection to your evaporator is loose or not connected properly.

If neither of these are the case then you can message me and I will tell you the only thing left it could be.

I would think that the dripping would come from the condensation of humid air (these cars aren't sealed as tight as new cars) on the flexible plastic A/C hoses that have the cold air blowing thru them......the water condenses on the hose and drips off at the lowest point of the hose as routed behind the Dash.........Just my $.02

Ken

You'll get condensation at the outlets, especially if they are made of metal (assuming you have the A/C on and the top down on a humid day).

To clarify, this is not condensation leaking from the inside of the case, but forming on the outside of the case and cooling ducts.
I double checked my drain. It is not leaking inside the car.
The drain fitting on the case had been cracked & repaired before I bought the car, and I bumped & cracked the outlet repair again during my rebuild last winter, but repaired it very securely with epoxy putty. The drain hose is 3/8 ID fuel line, and I can blow easily through it when I disconnect it at the case filling. The line runs slightly downhill to the front of the kick panel, then down through the rocker, exiting behind the front tire.
I also connected another piece of hose to the fitting & blew through it to verify it is not plugged.
The unit is a V/A Gen II Compact system.
As it was still dripping yesterday (36 hours after last use), it is obviously freezing up during extended use.
I think it only makes sense to try to eliminate or minimize the freezeup. I know improper R-134 level can cause that. Does anything else cause freezeup?
It was properly filled to V-A spec. (1.8#) a couple months ago.

They also publish the following specs...
I will get these checked next.

High-side Pressures:
160 to 270 PSI.
NOTE: General rule of thumb is two times the ambient (daytime) temperature, plus 15 to 20%.
Low-side Pressures:
10 to 20 PSI in a steady state.
Center Duct Temperature:
36 ̊F to 46 ̊F.

I will report if these are still in spec...

Thanks to all for weighing in!

Bill

I think the VA controller uses a thermistor to monitor the evaporator temperature and turns on the heat when it gets close to freezing. Is your heater control valve working properly?

Don

I just had my system charged for the first time ever and this was my experience as well. Getting a few drips from the vent tubes while cruising down the hwy. My wife was more alarmed than I was.