AC Refrigerants

[Patrick H.]

Re: AC Refrigerants: Update

Everyone,

I have visited the site http://www.epa.gov/spdpublc/title6/609 and found it to be very informative. It states that HC-12 DOES contain flammable substances, and is illegal. It also lists several R-12 substitutes, and many contain mixtures which include R-22 or R-134, some well known refrigerants.

I am going to do a little investigating, and hopefully can update everyone on these in the future.

Anyone with direct experience with alternate refrigerants OR converting a 71 or 72 to R-134a, please let me know.

Thanks!

Patrick Hulst

[Patrick H.]

Re: AC Refrigerants: Update

Everyone,

I have visited the site http://www.epa.gov/spdpublc/title6/609 and found it to be very informative. It states that HC-12 DOES contain flammable substances, and is illegal. It also lists several R-12 substitutes, and many contain mixtures which include R-22 or R-134, some well known refrigerants.

I am going to do a little investigating, and hopefully can update everyone on these in the future.

Anyone with direct experience with alternate refrigerants OR converting a 71 or 72 to R-134a, please let me know.

Thanks!

Patrick Hulst

[Jack H.]

Re: AC Refrigerants: Update

I got my '71 SB A/C up, running, and debugged using Forane 409. It's cheap and readily available but you won't find it at automotive shops because it's used primarily in commercial refrigeration systems. Ran very well, with one Catch-22.

Has a slightly higher head pressure in the system vs. R-12. A-6 compressor for '71 has a pressure relief valve to protect against overfill. The Forane 409 would last 1-2 months before it needed a 'top off'....

But, I was able to run the summer and 'debug' the system (test integrity) and at $2/lb vs. $40-60/lb it was worth it's weight in gold! Once I was happy that A-6 compressor was intact along with hoses/connectors, I sucked 'er dry and refilled with R-12. Holding nicely now some two years later!

[Jack H.]

Re: AC Refrigerants: Update

I got my '71 SB A/C up, running, and debugged using Forane 409. It's cheap and readily available but you won't find it at automotive shops because it's used primarily in commercial refrigeration systems. Ran very well, with one Catch-22.

Has a slightly higher head pressure in the system vs. R-12. A-6 compressor for '71 has a pressure relief valve to protect against overfill. The Forane 409 would last 1-2 months before it needed a 'top off'....

But, I was able to run the summer and 'debug' the system (test integrity) and at $2/lb vs. $40-60/lb it was worth it's weight in gold! Once I was happy that A-6 compressor was intact along with hoses/connectors, I sucked 'er dry and refilled with R-12. Holding nicely now some two years later!

[Dick W.]

Re: AC Refrigerants

HC 12 is an EPA approved replacement for R-12. However there are drawbacks to this and all the other approved refrigerants with the exception of R134-a. The vast majority of shops having the equipment to service, reclaim, and or recycle freon are equipped to do so for only R-12 and R134-a. Even though HC-12 and the others are "enviromentally friendly", they still require service including removing the refrigerant from the system. It is against the law to "dump" any refrigerant into the atmosphere. It takes an A/C refrigerant recovery machine that is designed for the specific freon that you are working with. I personally have not seen any machines that work with anything but R-12 and R134-a.

The cost of a changeover kit, which includes the fittings, correct oil, and required decals, is about $50-60. R-134-a is about $6.00 or so a pound. With the majority of the systems taking less than 3# of R-134-a, to me there is not a great difference in the cost.

The only time that it is economical to change the freon over is when it is necessary to replace a major component. It makes no sense to change over just because you want to. R-12 is still available and will be for some time. Expensive, but available. If you do have to changeover the system just make sure that you remove as much of the oil in the system as possible, replace the drier, and any "o" rings that have been disturbed.

I have converted several systems over, from mid-years to '88's with no complications. I have found out that it is very easy to overcharge with R134. It seems that the correct amount is more critical that with R-12. I changed over mywife's '72. Duct temperature last summer ranged from 42-48 deg. Very adequate. The compressor head pressure is well within tolerances for R-12.

I will attempt to help anyone wishing to convert their system over. Just send me an e-mail.

[Dick W.]

Re: AC Refrigerants

HC 12 is an EPA approved replacement for R-12. However there are drawbacks to this and all the other approved refrigerants with the exception of R134-a. The vast majority of shops having the equipment to service, reclaim, and or recycle freon are equipped to do so for only R-12 and R134-a. Even though HC-12 and the others are "enviromentally friendly", they still require service including removing the refrigerant from the system. It is against the law to "dump" any refrigerant into the atmosphere. It takes an A/C refrigerant recovery machine that is designed for the specific freon that you are working with. I personally have not seen any machines that work with anything but R-12 and R134-a.

The cost of a changeover kit, which includes the fittings, correct oil, and required decals, is about $50-60. R-134-a is about $6.00 or so a pound. With the majority of the systems taking less than 3# of R-134-a, to me there is not a great difference in the cost.

The only time that it is economical to change the freon over is when it is necessary to replace a major component. It makes no sense to change over just because you want to. R-12 is still available and will be for some time. Expensive, but available. If you do have to changeover the system just make sure that you remove as much of the oil in the system as possible, replace the drier, and any "o" rings that have been disturbed.

I have converted several systems over, from mid-years to '88's with no complications. I have found out that it is very easy to overcharge with R134. It seems that the correct amount is more critical that with R-12. I changed over mywife's '72. Duct temperature last summer ranged from 42-48 deg. Very adequate. The compressor head pressure is well within tolerances for R-12.

I will attempt to help anyone wishing to convert their system over. Just send me an e-mail.

[Jack H.]

Re: AC Refrigerants

Comments here:

(1) Your local Mr. Goodwrench and/or automotive repair facility is NOT

the only place you can get HVAC systems worked on.

(2) Your local phone books are filled with licensed HVAC contractors

who ARE qualified to work on heating cooling systems.

(3) MANY fixed location facilities use R-12 as a refrigerant in MUCH

larger volume/quantity that the simple 3.25 lbs in your Corvette

A-6 compressor system.

(4) Yep, you'll only see two kinds of re-cycle/recovery systems down

at the automotive garage, but there are MANY other refrigerants

actively serviced by independent HVAC contractors who do not

concentrate on automotive/mobile applications.

(5) Some can/will work on your car IF you approach and reasonably

explain you're trying to preserve/maintain a classic automobile.

(6) You might be pleasantly surprised at how cost effective it is to

use an independent HVAC contractor at his full hourly rate vs.

the n-tuple markup through the automotive distribution/repair

channel.

(7) Every time you turn around at an automotive A/C shop, they

usually 'hit' you to replace the evaporator/dryer or all bets

are off on warranty. I know of no current source for factory

original AC-Delco evaporator/dryer units (original size/shape

with original replaceable sight glass) and I check 'em for

factory originality when I'm judging....

(8) I believe you can re-claim/restore your original evap/dryer

unit instead of 'chucking' it.

[Jack H.]

Re: AC Refrigerants

Comments here:

(1) Your local Mr. Goodwrench and/or automotive repair facility is NOT

the only place you can get HVAC systems worked on.

(2) Your local phone books are filled with licensed HVAC contractors

who ARE qualified to work on heating cooling systems.

(3) MANY fixed location facilities use R-12 as a refrigerant in MUCH

larger volume/quantity that the simple 3.25 lbs in your Corvette

A-6 compressor system.

(4) Yep, you'll only see two kinds of re-cycle/recovery systems down

at the automotive garage, but there are MANY other refrigerants

actively serviced by independent HVAC contractors who do not

concentrate on automotive/mobile applications.

(5) Some can/will work on your car IF you approach and reasonably

explain you're trying to preserve/maintain a classic automobile.

(6) You might be pleasantly surprised at how cost effective it is to

use an independent HVAC contractor at his full hourly rate vs.

the n-tuple markup through the automotive distribution/repair

channel.

(7) Every time you turn around at an automotive A/C shop, they

usually 'hit' you to replace the evaporator/dryer or all bets

are off on warranty. I know of no current source for factory

original AC-Delco evaporator/dryer units (original size/shape

with original replaceable sight glass) and I check 'em for

factory originality when I'm judging....

(8) I believe you can re-claim/restore your original evap/dryer

unit instead of 'chucking' it.