neo,

The expansion valve's main function is to change the pressure from high to low, thus, changing the temperature properties of the freon. Low pressure running on the cooling coil produces low temperatures.

 

Yes, I know... I was just trying to see if that is what Hydra was talking about... In Audi's and VW's, the expansion valve is about 3" long and looks like a mini filter... I know all about expanding and compressing gasses... Especially when a hose bursts in your face and that hose happens to be full of SF-6...

 

sounds like you did something you shouldnt have???????


either that or have a good (long) story to share w/ us


and hydra, i agree with just having a shop evacuate/recharge the a/c system, not something i would be willing to do myself w/o the proper (most likely very expensive) equipment or training

 

LOL! Nope, just a malfunctioned hose...

 

The filter I am referring to is the dryer.

 

Ya,

I'm going to recharge to about 40psi and try that. If that doesn't take care of it it's off to the shop.


Nope........ The dryer

 

So I installed 12oz freon and whatcha know........ Got it!

Pressures on the low end are 52psi max and drop to about 30psi. I am going to get one more can because as it is cool it is not cold and I think I am totally out. Max freon lbs for my system iss 1.88 lbs because I have a dual unit. 1.75 lbs without dual unit system. 2-12oz cans should be close to max because of the oil I already installed to take the 0.38 lbs overage.

I will be careful though, as I don't want to over fill!

 

Hydra,

DO NOT GO BY the max fill on your A/C system. The only time you go by that number is if you are filling up your A/C system from COMPLETELY EMPTY. Without knowing exactly how much freon you presently have in your system, more or less, you will overfill and risk damaging your compressor.

If you already added one whole can and judging by the pressure readings on low side of your D if 30 psi is based on engine idling at 1500 rpms, it should be close to max already.

at this point, I would guess you may have an issue with your H valve that may be clogged due to water contamination (freezing up). I would have your system evac'ed really good and then refill again and see what happens. If you have a good set of gauges so you can connect to the high side, then you can see a better picture of what your A/C is doing.

A good set of gauges will show you both high side and low side readings that can give you some quick answers. Each type of freon grade (134a, 12, 22, etc) has a different pressure reading to obtain the same temperature difference.

If you see issues on the low side, check the high side, if high side pressure/temp are normal, then something may be wrong from the hvalve to the compressor. If there is something wrong with the high side, it will affect your low side.

 

I really need to buy a set of gauges....... Will do when I can.

Those numbers where right at about 1500-1800 rpm. Still think It could take a little more. After installing 1/2 the 12oz can it wasn't blowing cold or really anything and after the rest went in you could see as well as hear the difference plus it went cold. I'm going for one more can but before installation I think I 'm going for the gauges.

 

Today is the first day to take my durango to work. It needs to be driven on the highway and let her rip. Been in the garage too long. It's 81 degrees in DFW. Little humid so turn on the A/C. Fan speed setting set to 2nd from lowest setting. Man, ice cold air. When I came back home, I took out my infrared thermometer and it was blowing at 25.7 degrees F! now that's freaking cold air!

I am holding around 35 psi at 1500 rpms on low side. my high side is broken so I cannot tell you what the high side is.

But having a dashmat over my dash and having my low side piping insulated are some of the factors of having such cold air!