A/C recharge question

[Sign Guy]

My compressor kicks on and off due to a low charge. How hard is it to do the recharge yourself if you can get your hands on the gauges? The system has not been upgraded and I'd like not to have to do that. The old chemistry blows colder. I understand that shops have to purchase a $10K plus machine to do this and therefore charge the customer accordingly. Any tips?

Thanks!

[TNRRClassic]

First, you don't have to have any sort of outlandish equipment to work with R12. You only have to be a licensed technician and recapture any refrigerant from the system. No releasing it into the atmosphere, you know. You may have to call a few places before you find one who will go to the trouble of dealing with R12, but any good shop will. A full recharge may run $150 or thereabout, but you will need to find the leak so that you don't have to do this again soon. Many AC shops do not want to deal with R12, so they will fill you with all manner of bull.

Switching to R134, Freeze 12, or another refrigerant is another possibility, but they generally run a higher pressure, and you should at least aggressively vacuum your system, possibly use a cleaner to remove the old oil, and change your receiver/dryer. Your AC was designed around R12, and it will function more optimally using the original product.

[RageRover]

Originally Posted by TNRRClassic

First, you don't have to have any sort of outlandish equipment to work with R12. You only have to be a licensed technician and recapture any refrigerant from the system. No releasing it into the atmosphere, you know. You may have to call a few places before you find one who will go to the trouble of dealing with R12, but any good shop will. A full recharge may run $150 or thereabout, but you will need to find the leak so that you don't have to do this again soon. Many AC shops do not want to deal with R12, so they will fill you with all manner of bull.

Switching to R134, Freeze 12, or another refrigerant is another possibility, but they generally run a higher pressure, and you should at least aggressively vacuum your system, possibly use a cleaner to remove the old oil, and change your receiver/dryer. Your AC was designed around R12, and it will function more optimally using the original product.

x2. Yeah, any mobile air conditioning system on any car, should last the life time of the vehicle....in the perfect world, or when the vehicle has been taken real great care of. R12 is becoming a rare refirgerent to get ahold of, but can be ordered through MACS certified technicians at any shop that services mobile air conditioning. I am MACS ceritified, so technically I could order R12, but don't have the equipment to evacuate the old system, find the leak, or the tools to repair any thing on mobile A/C. The best solution I was told, and it would cost a very pretty penny, would be to retrofit the whole system to an R-134a system just like he said. Consists of replacing reciever-drier, maybe compressor, restriction device (maybe), and when it is all said and done would be a better, environmetally safe, and longer life span than R-12. It all depends what's in your wallet.

[TNRRClassic]

The issue if you do choose to convert to another refrigerant is that you should change AC hoses. As they age, they crack and develop leaks. Often old R12 systems will not leak as bad as R134A, due to the accumulated oil and the larger size of the R12 molecule. It is often the case that an old R12 system that leaks down over the period of a year will do so much more rapidly if converted to R134A. Freeze 12 is simply R134A, with a portion of R142 IIRC to help it be more compatible with the oil in the R12 system.

Converting to R134A can be a mixed bag, in that some people have great success simply vacuuming and recharging with R134A, while others find no satisfaction. If you have a good AC shop, and plan to keep the Rover for a LONG time, converting can be successfully done and save money over constantly recharging with R12. That option could cost near $1000, if you choose to "go all the way", but if $150 is the going rate in your area to recharge with R12, it would pay for itself over a few years. By the way, you are not actually supposed to recharge with R12 without repairing the leak. Releasing R12 into the atmosphere is not exactly legal or environmentally friendly. By the same token, while not destructive to the ozone layer, R134A is a greenhouse gas, and is relatively toxic if you breath too much.

[Elemental]

Most certainly retrofit it to r-134. It works great on a Classic, and its cheap and easy to get. Its easy to do. I dont know how handy you are, But to do it right, you would swap out the drier and the orings.... A Saturday afternoon if your handy and familar with your car.

The RIGHT way is to pull a vacuum to remove any left over mositure and confirm the system will hold pressure.

R-12 is done.... It doesnt work any better, its expensive and tough to get... There is no good reason to use it.

[TNRRClassic]

Well, it may or may not be as simple as all that. In a fair number of cases, a good vacuuming, o-ring replacement, receiver/dryer change, and recharge with R134A does work to great effect. However, it can really be difficult to get all of the old oil out of the system, so very often a cleaning solution will be circulated to remove it. Some shops prefer to use it, while others do not. However, don't think that you are guaranteed success with that procedure, as you haven't repaired leaks outside of the o-rings. If you have a separate leak, you will need to do more.

[Elemental]

If he swaps the Drier and uses Ester oil (NOT PAG!) the left over oil wont be a problem.

[Geoffrey F Miller]

It is said that R13 and R134 will work OK, but they react with the lubricating oil in the R12 system which then goes on to rot the seals eventually.

If R12 escapes, it reacts with water (eg the tears in your eyes) to form a highly corrosive compound, so take great care!

R45 is a non-CFC refrigerant which is fully compatible with the old R12 systems. I had mine replenished (not exchanged) with this last year, first top up in over 20 years and it's brilliant now. No other replacement parts were required.

[Elemental]

Easter oil does not react with r-12 or it's oil.


You guys are making this harder then it needs to be. !34 willbe colder then you will ever ask it to be, and it's easy,safe and cheap.