A/C recharge "How-to"?

[Sasquatch]

The Subaru was cooking us, needing $200. In WalMart I found this cool package, consisting of a can of refrigerrant, filling hose, and integrated gauge for $20. I bought it, filled the system according the the gauge, and it works great. I wish I would have something so simple years ago when I cracked the compressor on my Accord by guessing how much to put in.

Was it a blue can with red hose? THAT is EXACTLY what I bought for the VW a couple years ago, but they were all out in that last heat wave which made me go to the Autozone. Works great!

[howardc64]

Hi:

Thinking about to take my 01 V70 T5 to AutoZone to get the A/C recharged.

But I would like to understand the basic theory of operation and what they did at AutoZone to avoid any long term damages/expensive repairs. I worry about running into a worker that doesn't know what they are doing for filling on the high pressure side. Here are some online resources providing helpful explanation

http://wiki.ehow.com/Fix-Cars-Air-Conditioning

Did they drain the old refrigerrant and vacume pump the system? I would guess not for $10 + free charging service. If they don't do this, does anyone know if moisture corrosion problems in the AC system is common for these cars?

When they filled on the high pressure side, how did they ensure adequate pressure was available? How do you know when the system is filled and not over filled? Did they look for a specified psi? The following link seems to suggest high side psi is a multiple of the ambient temperature

http://www.firstfives.org/faq/AC/ac_charge.html

Anyways, trying to learn as much as possible before deciding if I should dive into DIY or AutoZone.

[Sasquatch]

Hi:

Thinking about to take my 01 V70 T5 to AutoZone to get the A/C recharged.

But I would like to understand the basic theory of operation and what they did at AutoZone to avoid any long term damages/expensive repairs. I worry about running into a worker that doesn't know what they are doing for filling on the high pressure side. Here are some online resources providing helpful explanation

http://wiki.ehow.com/Fix-Cars-Air-Conditioning

Did they drain the old refrigerrant and vacume pump the system? I would guess not for $10 + free charging service. If they don't do this, does anyone know if moisture corrosion problems in the AC system is common for these cars?

When they filled on the high pressure side, how did they ensure adequate pressure was available? How do you know when the system is filled and not over filled? Did they look for a specified psi? The following link seems to suggest high side psi is a multiple of the ambient temperature

http://www.firstfives.org/faq/AC/ac_charge.html

Anyways, trying to learn as much as possible before deciding if I should dive into DIY or AutoZone.

I trust the monkeys at Autozone no less than the ones at the stealership. They have a pretty elaborate gizmo with lots of gauges and other contraptions which the kid seemed to know what he was doing. Like I said, I was right there versus who knows what is happening at the stealership.

[howardc64]

Called 2 AutoZones in the Seattle area and visited one and called the other in Portland OR area.

None of the AutoZone people I spoke with knew about high pressure side recharge. They repeated the common knowledge that R134a lables all say to charges on the low side. I asked what tools they have for DIY. They said the charging kits + connectors + hoses are all for sale (I took this meaning they have none to borrow)

Holding off DIY until more definitive directions.

[Sasquatch]

Everything I read said use the low side also. That is the one way up in front above the radiator, right? I would imagine they put it there for easy access. Imagine that. If they only did that with oil filters. My brother's RX-7 had the oil filter up top and it drained back into the engine when off, so all you do is unscrew it with no mess at all.

Anyhow, 'tis the season for charging AC and another trip to Walmart tonight should do it if they are not out yet. I figure I'll get 3 cans and do 1 1/2 cans each in the Volvo and Jetta.

[Sasquatch]

Well, I went and bought a new kit at WallyWorld and a few cans of spare 134 (you just know when there is a heat wave that they'll be out). This kit has a nicer valve and a nicer gauge, so should last a while. Of course it was also more expensive.

Anyhow, I charged up the inlaws' Jetta again and everything went perfect, according to plans and jiving with past experience.

Went to fill the Volvo (the valve right at the front near the bumper, remember?), and what should have been simple and easy fell flat on its face. The Volvo uses a non-standard size valve.

So, anyone know what size valve this is, and where I might find an adapter?

Otherwise, I might just use the rest of the first can (1/4 left) for my neighbor's car, or just let it out and call it a day. It was still a savings over the cost to charge just the one car (Jetta), so was still worth the price.

Thanks.

[funglenn]

It is the low side do only the high side if you want to get yourself hurt. All the cans are not wrong, only the advice of the poster was. It is low side!

[Sasquatch]

I think we are all clear on that.

Now I'm just looking for an adapter for the valve size. The one on the Volvo is bigger than the standard size which is on most other cars.

[shawn_75]

Although you agree it is the low side to connect the can to, are you still trying to connect to the fitting up front by the radiator? That fitting is the high side. Have you tried the other fitting? The high and low pressure side fittings are different sizes on purpose.

Shawn

[Sasquatch]

Although you agree it is the low side to connect the can to, are you still trying to connect to the fitting up front by the radiator? That fitting is the high side. Have you tried the other fitting? The high and low pressure side fittings are different sizes on purpose.

Shawn

WHAT other fitting? You mean to tell me they put the one you need access to somewhere buried inside the engine bay and one you don't use up front IN THE WAY?

Got a diagram? Now I'm concerned.


OK, fact time:

Fill on the low pressure side. Check
Low pressure side fill point is located __________ (fill in the blank).
The 6Nm valve connection up front near the radiator is for _____ pressure (fill in low or high).


Thank you.