Author Topic: R12 Freon upgrade  (Read 3134 times)

Offline jptiger

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R12 Freon upgrade
« on: June 07, 2020, 12:31:42 PM »
I have a 92 GMC Sierra. How expensive and difficult is it to upgrade the air conditioning from old Freon to new? Can’t remember the numbers r13 to f134a?


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1977 GMC Sierra Grande K15 swb
1992 GMC Sierra K1500 ext cab

Offline JohnnyPopper

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Re: R12 Freon upgrade
« Reply #1 on: June 07, 2020, 06:08:52 PM »
It's not too hard, but you have to have a pro do the evac and refill.

Starts with adapters that screw on to your current high and low valves. Cheap find at auto parts store.

If you're system is sealed, and is holding gas, you might get away with not having to change the dryer unit.

Expect someone to scream that you MUST change the dryer, but I have experienced not having to and being frozen using the old one.

If your system is not sealed, than change it, as it has been open to humidity and is probably saturated to the point of being ineffective.

Following that you will need a pro to evacuate the old R12 and replace with R134.

Make sure he adds oil too. 

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1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline VileZambonie

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Re: R12 Freon upgrade
« Reply #2 on: June 07, 2020, 06:29:33 PM »
It's not an upgrade, it's a retrofit. R12 to R134A conversion is easy if you have the means to do it.
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Offline Shifty

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Re: R12 Freon upgrade
« Reply #3 on: June 08, 2020, 09:25:18 AM »
As cheap as an accumulator/drier is, change it.  It will have mineral oil in it, which is the bane of R134a, and needs to have ester oil in to lube your compressor.  Change the orifice tube also, it has a little screen on it that is usually partially plugged after years of use. 
87 V20 Standard Cab Longbed (current)

87 R30 3+3 Longbed (days of yore)

98 C2500 ext cab longbed

Offline JohnnyPopper

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Re: R12 Freon upgrade
« Reply #4 on: June 09, 2020, 07:14:54 PM »
As cheap as an accumulator/drier is, change it.  It will have mineral oil in it, which is the bane of R134a, and needs to have ester oil in to lube your compressor.  Change the orifice tube also, it has a little screen on it that is usually partially plugged after years of use.

Good catch Shifty one!  8)
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline ehjorten

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Re: R12 Freon upgrade
« Reply #5 on: July 17, 2020, 04:34:34 PM »
Get your R12 Certification and go buy some R12 and recharge your system!  Becoming a R12 Certified Tech is easy and inexpensive.  Commercial A/C systems all still use R12.
-Erik-
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1977 K20 Silverado - 350, THM350, NP203, 14 bolt FF, D44, Stock Lift on 31s
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Offline Shifty

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Re: R12 Freon upgrade
« Reply #6 on: July 17, 2020, 05:38:31 PM »
Get your R12 Certification and go buy some R12 and recharge your system!  Becoming a R12 Certified Tech is easy and inexpensive.  Commercial A/C systems all still use R12.
That's R22, and it's being phased-out in favor of RS44b.  Other than finding someone with a cache of R12, it's pretty much done. 
87 V20 Standard Cab Longbed (current)

87 R30 3+3 Longbed (days of yore)

98 C2500 ext cab longbed

Offline SilverMiner

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Re: R12 Freon upgrade
« Reply #7 on: July 18, 2020, 07:05:19 PM »
Get your R12 Certification and go buy some R12 and recharge your system!  Becoming a R12 Certified Tech is easy and inexpensive.  Commercial A/C systems all still use R12.
That's R22, and it's being phased-out in favor of RS44b.  Other than finding someone with a cache of R12, it's pretty much done.

May I respectfully disagree. R12 is economically available (only ~2x the cost of R134 at WalMart) via multiple online sources, primarily eBay. Unfortunately most of what is sold there (and at the cheapest price) is new and illegal production from China. However there is still a large supply of reclaimed and recycled R12 available even to the automotive hobbyist as long as they spend $20 and take a simple open book test to get their EPA 609 certificate. The source of the reclaimed R12 nowadays is primarily commercial HVAC that have finally made the obligated conversion. The farther you live into the sticks the more likely you can find recycled R12. The only potential downside is that the recycled stuff in my experience is frequently only available in 30lb containers which vastly exceeds the quantity I actually need and therefore more expensive. But many AC shops in my area of the Northern Rockies will still service R12 systems at a reasonable price.

Offline Shifty

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Re: R12 Freon upgrade
« Reply #8 on: July 20, 2020, 11:39:26 AM »
Interesting...hasn't been available in Arizona in over a decade.  I get shops calling me for it at least once/week. (I do wholesale parts, air-conditioning is a huge deal in AZ).

https://en.wikipedia.org/wiki/Dichlorodifluoromethane
87 V20 Standard Cab Longbed (current)

87 R30 3+3 Longbed (days of yore)

98 C2500 ext cab longbed

Offline SilverMiner

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Re: R12 Freon upgrade
« Reply #9 on: July 20, 2020, 05:51:55 PM »
Interesting...hasn't been available in Arizona in over a decade.  I get shops calling me for it at least once/week. (I do wholesale parts, air-conditioning is a huge deal in AZ).

https://en.wikipedia.org/wiki/Dichlorodifluoromethane

Its common enough around here you can still acquire some from craigslist. This sale has been active for over 2 months so I have some confidence it will still be there by the time you click on it: https://lewiston.craigslist.org/pts/d/grangeville-almost-full-30-bottle-of/7132866325.html

Arizona has a large mining industry but has comparatively few deep underground mines which require chilled ventilation. Those deep underground mines (which are also many decades old) are what are producing the majority of the glut of recycled HVAC R12 in my low population area. Also, it simply doesn't get as hot for as long around here so the other commercial HVAC have gotten away without replacement for an inordinately long time. Are there burdensome restrictions to ship it down to where it is in demand? If not, perhaps we've identified a business opportunity.

Also, 14oz cans from China are ridiculously easy to acquire off of eBay. They even arrive via USPS! But I don't mess with them anymore.


Offline jptiger

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Re: R12 Freon upgrade
« Reply #10 on: September 16, 2020, 09:28:51 PM »
Thank you all for this information. Appreciate it!


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1977 GMC Sierra Grande K15 swb
1992 GMC Sierra K1500 ext cab