What tools needed for A/C recharge?

[at7we2]

What tools do I need to top-off the refrigerant in my GN? It was converted to R134a a couple of years ago. I could pay a shop to do it, but I've wanted to buy the tools and learn to do at least a basic service like this myself for a long time. I've seen the inexpensive recharge kits at the local parts stores, but I'd like to go ahead and invest in some decent quality tools for future use. Can someone recommend a brand, type and source for automotive AC service tools (manifold gauges, etc.)?

I've done a little research and shopping online and there appears to be a wide range of prices and different configurations for even just the gauges - brass versus aluminum manifolds, digital versus analog gauges and so-on. From what I can tell, it looks like Mastercool and Robinair might be some of the better gauges out there, but I'm not sure. The residential AC tech we had out at the house recently was using a Yellow Jacket gauge manifold.

I've seen just the gauge manifold with hoses sold without any other tools but I've also seen them sold with a can adapter and even with a can adapter, thermometer and vacum pump all together. Right now I think I just need a decent set of gauges and a can adapter just to top-off the system, is there anything else?

Looking for input from those who know.

Thanks for reading.

Rob

 

[Morbid]

Yellow Jacket, Mastercool, CPS, and Robinair/SPX all make good stuff. I would use any of the them.

As with any other tool you will find different classes. Those being cheap, pro-sumer, and professional. Case in point the A/C guy your were talking about was using a Yellow Jacket Manifold. Their stuff is pricey.

Answering your question directly however. At minimum you'll need a good set of gauges set up for the refrigerant your using. If your buying the set new they usually come with hoses and the side couplers you'll need.

Anything after that depends on how deep you want to go. A decent vacuum pump is another required item if you plan on doing any work on the system (you'll need to vacuum the system down before re-charging after opening it up).

Getting deeper if you get a pump you might also want to get a vacuum gauge. This will tell you how much vacuum your pulling the system down to (the gauges on the manifold only reads pressure). This would also require getting another set of hoses since the charging hoses that come with the manifolds aren't reliable for measuring vacuum.

If you want to do some troubleshooting for leaks you'll need a Leak Detector.
Some are electronic others use dye. I prefer not to inject anything that doesn't belong in the system so I use a electronic on.

You can re-charge the system using the cans or buy a bulk container and a charging scale.

The whole ball of wax (if you expect to work on a system that has a charge but don't want to take it to the shop to evacuate it) is to buy a recovery machine or better yet a reclaiming/recycle machine so you can re-use the stuff your pulling out.

Technically your suppose to take some test to be "Certified" to reclaim refrigerant because of the environmental issues.

I re-did my system right last season (new condenser, Accumulator, hoses, orifice tube, and measured fresh oil) with everything except the recovery/reclaim machines and charging scale.

Got everything New in Box off EBay. Each item for between 50%-75% off.

Re-cap

Needed:
Manifold (Brass is the old stuff the newer ones are Aluminum) but the difference is cosmetic.Charging hoses and Couplers.

Needed for troubleshooting and repairs:
Vacuum pump and a set of hoses rated for holding vacuum.
Leak Detector

Extra stuff (not required for basic hobbyist stuff)
Recovery machine or Reclaim/Recycle machine + tank
Charging Scale
Vacuum gauge

HTH
Greg

 

[at7we2]

Wow! Thanks Greg! That's a wealth of well organized information! You answered everyone of my questions - thank you.

For now, I think I'll get just what's needed to top off the system, (gauge manifold, hoses, can adapter) but I'll invest in decent stuff and buy what I need for a larger job later. It would be nice to be able to service and repair these systems for friends and family, but I know there is a license and certification involved.

based on your post, I'd guess you're either a P.E. or a teacher or both.

That post might be worth a sticky...moderators?

 

[Morbid]

based on your post, I'd guess you're either a P.E. or a teacher or both.

Your welcome. My Engineering degree's are in un-related technical fields but after getting them I find I like to research everything to understand how it was designed and supposed to work.

Like I said before, I did a proper 134a conversion to my Regal last year and wanted to get it right. So I got all the tools and read a lot of material. The GM Factory Service Manual is a great source. It deals obviously with R12 but the equipment is the same and so are the diagnostics.

Ackits.com has some very useful information/how-to's over there as well as forums dedicated to Automotive A/C service and repair.

Once you get a set of gauges I strongly suggest you read the instructions and learn how to use them safely. Also get a chart of refrigerant/pressure-temperature. It will tell you what the pressure of refrigerant is at a given temperature so you know what your looking at.

Lastly remember the gauges only read pressure, they can't measure accurately how much refrigerant is in the system. There is only one sure way to know and that's to evacuate the system down to zero and recharge to the specified level for the system your working on.

The most common reason for poor A/C system performance outside of leaks and/or air in the system is over and/or under charging.

Like everything else one usually pays someone else to do there's a reason. Your paying them because they have the tools and the knowledge (hopefully) and your paying for their time to use deploy them.

Make sure you have both before you set out to remove their time from the mix. Otherwise you'll end up paying them anyway and what savings is that?

Good Luck