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Air Conditioning
- Thread starter jjbunn
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Look for the blue cap, the "suction" side. it'll be the larger diameter of the two lines you have. Another way to find it is to find the "S" on the compressor (as opposed to the "D"). Under NO circumstances connect that toy "kit" fitting to the high ("D" for discharge) side of the system!!! Head pressures are as high as 500 PSI. You can imagine what that'll do to that li'l tin of gas. A/C is an abomination and contrary to nature. Be careful playin' with it, I'd say find someone familiar with refrigeration systems and ask guidance.
David_DuBois
Jedi Warrior
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Julian - Wear goggles when working with the refrigerant - youdon't need a frozen eyeball
Cheers,
Cheers,
OP
jjbunn
Jedi Knight
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OK so the Freeze 12 kit comes with two coupling adaptors: one blue and one red. They fit over the existing R12 connection ports on the low and high pressure side of the compressor, respectively. The R12 ports have schrader valves, so do the Freeze 12 couplers. It seems to me that I need to remove the valve from the R12 port before attaching the coupler, since otherwise it will never pass gas because the pin will never get pushed in on it.
But doing that will open the system to the atmosphere, and I don't want that.
Is that right: removing the schrader valve (simply a matter of unscrewing it) will open the system?
But doing that will open the system to the atmosphere, and I don't want that.
Is that right: removing the schrader valve (simply a matter of unscrewing it) will open the system?
R
RonMacPherson
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Take your Freeze 12 kit, and very carefully dig a big, deep hole and bury it!!
It is not freon. It is flammable. I belong to iatn(International Automotive Technicians Network) and we had this discussion going on a couple of years ago.
No conscientious professional will use this stuff. In fact there was such a negative feedback to the Freeze 12 folks that they lowkeyed the sales for a while and then directed it to the over the counter, fix-it-yourself folks.
It is DANGEROUS to use and I recommend you head down to your nearby Napa or Carquest store and get a non lethal a/c fill kit. They have the bottles and kits available.
It is not freon. It is flammable. I belong to iatn(International Automotive Technicians Network) and we had this discussion going on a couple of years ago.
No conscientious professional will use this stuff. In fact there was such a negative feedback to the Freeze 12 folks that they lowkeyed the sales for a while and then directed it to the over the counter, fix-it-yourself folks.
It is DANGEROUS to use and I recommend you head down to your nearby Napa or Carquest store and get a non lethal a/c fill kit. They have the bottles and kits available.
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jjbunn
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Hi Ron,
I've heard this elsewhere, but the cans specifically state it is not flammable. Also, on https://www.freeze12.com it states "FREEZE 12™ is non-flammable and contains no CFC'S." I believe it's 80% R134a. On the rennlist forum there was a heated debate about the merits or otherwise of Freeze-12. Some folks despise it, and others say it works just fine. I'm going to give it a try, because I'm a born experimentalist, and there doesn't seem much to lose (my A/C is blowing warm: I had it refilled with R12 last year for around $200, and I don't fancy that again).
But I do thank you for your warning, which makes me quite (even more) cautious.
For the valve problem, I just figured it out. On closer examination of the valves and couplers, it's apparent that the converter coupling's valve pin is pushed in by the coupler hose fitting, and it then pushes in the pin on the R12 adapter valve, so opening the passage. Ther coupler hose fitting has a small protrusion in its centre that pushes on the pin as the coupler is screwed and tightened on the adapter.
My problem was that this protrusion was not adjusted correctly: it wasn't pressing the pin in far enough to engage and push the R12 pin in. After adjusting it somewhat, I can hear gas escaping from the R12 valve when I screw in the coupling hose.
So tomorrow I am going to try a fill.
I like the idea of having two valves in series: makes a leak much less likely!
I've heard this elsewhere, but the cans specifically state it is not flammable. Also, on https://www.freeze12.com it states "FREEZE 12™ is non-flammable and contains no CFC'S." I believe it's 80% R134a. On the rennlist forum there was a heated debate about the merits or otherwise of Freeze-12. Some folks despise it, and others say it works just fine. I'm going to give it a try, because I'm a born experimentalist, and there doesn't seem much to lose (my A/C is blowing warm: I had it refilled with R12 last year for around $200, and I don't fancy that again).
But I do thank you for your warning, which makes me quite (even more) cautious.
For the valve problem, I just figured it out. On closer examination of the valves and couplers, it's apparent that the converter coupling's valve pin is pushed in by the coupler hose fitting, and it then pushes in the pin on the R12 adapter valve, so opening the passage. Ther coupler hose fitting has a small protrusion in its centre that pushes on the pin as the coupler is screwed and tightened on the adapter.
My problem was that this protrusion was not adjusted correctly: it wasn't pressing the pin in far enough to engage and push the R12 pin in. After adjusting it somewhat, I can hear gas escaping from the R12 valve when I screw in the coupling hose.
So tomorrow I am going to try a fill.
I like the idea of having two valves in series: makes a leak much less likely!
Since you are in a cautious mood you might want to buy some suitable gloves.
Freeze burn is extremely painful and leaves a nasty looking scar as well.
Try a scientific supplies place and get the ones which are a gauntlet type covering the lower forearms as well if you can.
Cheers , Pete.
Freeze burn is extremely painful and leaves a nasty looking scar as well.
Try a scientific supplies place and get the ones which are a gauntlet type covering the lower forearms as well if you can.
Cheers , Pete.
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Yup. First you should locate the leak. If it is blowing non-refrigerated air it has already been open to atmosphere; you can likely expect it to need a receiver/dryer as well if you want it to be efficient after it's been recharged. This is a PITA job on a 911, I know you're determined to have a go. It is truly a process requiring some tack 'n tackle missing from your kit. A vacuum pump is something of a requirement: you NEED to suck it down to at least 26 in/Hg for a minimum of 45 minutes for moisture to be removed from the system AFTER finding/fixing the leak, "rinsing" the system and R&R the dryer. A set of gauges appropriate to the refrigerant you're using is a good idea, a "sniffer" or other leak detection method is necessary... I expect you've done some research on this, it really is a chore if it is to be done to make it tight and reliable.
A/C service is one task for a facility with the gear and training to do it correctly. You can squirt some gas in it and hope, but that is going to (at best) just prolong the inevitable for less and less time at each attempt. Meanwhile OTHER problem$ are being introduced/exascerbated. You certainly are capable of doing it, but you need the "right stuff" for it to be correctly done.
That said; I've certified as an (NI)ASE wrench, iATN sign-up in '96 and additionally have Porsche factory training certs... even A/C... don't mean much, just evidence of an ill-spent youth. Do some more 'digging' and look to some local DIY enthusiasts for better support. Meantime; blow th' hatches and feel th' wind in yer hair. /bcforum/images/%%GRAEMLIN_URL%%/smirk.gif
A/C service is one task for a facility with the gear and training to do it correctly. You can squirt some gas in it and hope, but that is going to (at best) just prolong the inevitable for less and less time at each attempt. Meanwhile OTHER problem$ are being introduced/exascerbated. You certainly are capable of doing it, but you need the "right stuff" for it to be correctly done.
That said; I've certified as an (NI)ASE wrench, iATN sign-up in '96 and additionally have Porsche factory training certs... even A/C... don't mean much, just evidence of an ill-spent youth. Do some more 'digging' and look to some local DIY enthusiasts for better support. Meantime; blow th' hatches and feel th' wind in yer hair. /bcforum/images/%%GRAEMLIN_URL%%/smirk.gif
OP
jjbunn
Jedi Knight
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OK Doc et al ... great input. My theory is that I have a leak from one or both of the schrader valves, since when I remove the caps, I can see wetness inside. By attaching the Freeze 12 valves over the top, I'm hoping I will have no more leak. (The interesting and surprising fact I have learned about the valves is that it is the dust caps which are actually the main seals for the ports, rather than the schraders themselves.)
If this experiment doesn't work, I'm, taking it to the shop: I am realistic about my capabilities (and equipment)!
If this experiment doesn't work, I'm, taking it to the shop: I am realistic about my capabilities (and equipment)!
R
RonMacPherson
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Then perhaps they've changed their formulation in the last couple of years. On the schraeder valves. Most are common to pretty much all auto systems. Using a regular tyre schareder valve tool(little pickle fork) you can replace them. But make sure you get a/c valves from a parts store, Honda, GMC shop, etc...
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jjbunn
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Thanks Ron.
Status update: I added 1.5 cans of Freeze-12, and a can of oil. Ambient temperature is 24C (75F), temperature out of the main blower: 9C (48F).
Now I will watch it over the next couple of weeks.
(The cans of Freeze 12 got pretty chilly as I was adding them, but not too bad. I wore thick gloves and glasses throughout the procedure.)
Status update: I added 1.5 cans of Freeze-12, and a can of oil. Ambient temperature is 24C (75F), temperature out of the main blower: 9C (48F).
Now I will watch it over the next couple of weeks.
(The cans of Freeze 12 got pretty chilly as I was adding them, but not too bad. I wore thick gloves and glasses throughout the procedure.)
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clean all your lines (especially at any joint), and watch for traces of refrigerant oil around them over time. As the thing loses charge you may be fortunate enough to find the leak. Murphy's Law is in effect: most A/C leaks will be in a place where you don't have convenient access. Like the connections at the evaporator valve or the evaporator itself. Being a practiced contortionist is a helpful talent. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif
Back in the "R-12" days I installed/repaired car A/C units for a few years. Back then we could get cans of freon with a slightly heaver/red-colored oil that was marketed as "leak detector" oil. We found that if we put this stuff in with a normal freon charge that it would often seal-up the leak and the system was good to go for a very long time and if not them would leave a red trace at the leak. They may still sell something like that for the R(new stuff) systems. Worth a look.
Bill
Bill
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RonMacPherson
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You can get blue light pocket flash lights at most hardware stores for under $10. Even some of the keyfob lights pick up the dye stain. Try shopping around Might surpise yourself.