just wait till the new crap is "the thing" $1,000 for a 10 LB container.!!

no thanks, i will stick with my R-12 at $20 per pound

 

"while R-12 may be a CFC R134-A is still almost as bad" - tjc transport. Although I appreciate the permission to proclaim R-12 is a CFC. Or were you implying it is possible it is not? In any case fact being R-12 is a CFC. These classes of refrigerants are stable, and easily reach up to the stratosphere where the chlorine atom separates and picks up a free oxygen atom. Ozone, O3 is as the name implies, comprised of three oxygen atoms. Bingo Ozone is no mo' and turned into O2, oxygen... Wait. here's some more made up, "BS" - Hardscrabble. When Mr. chlorine beats up O3, O2 is not the only by-product. Good ol CIO, or chlorine monoxide shows up to really turn it up, he goes around and pulls ANOTHER oxygen atom away, and his buddy chlorine is a free agent once more, ready for more. R-134a is not nearly as bad. Why's that? Science, advancements in chemistry. See R-134a, or HFC-134a is only partially halogenated, it has had its dangerous chlorine atom removed from the mixture. It is Tetrafluoroethane, comprised of 2 carbon atoms, 2 hydrogen, and 4 fluorine atoms. Although R-134a is not PERFECT, it has greater heat transfer capability and is very safe. HFC-134a is used in the medical industry for those with lung problems. The "new crap" are HFOs, hydrofluoro olefins. AKA what 1234yf is probably going to completely phase out R-134a for newer production vehicles. It is chemically safe for Ozone, is a toxicity group A, flammability group 2L refrigerant. So no, not "HIGHLY flammable" - tjc transport. Which means it is safe, but is combustible under certain conditions and is to be considered (as measured by ASTM E681) mildly flammable, when flame is gone so is the flame propagation from the refrigerant. Also, the R-12 you advocate so much will produce phosgene gas when ignited . What's that? COCI2, a REAL life stopper...
Look, I know you guys mean well. but fact of the matter is R134a is a better refrigerant for these trucks long term. It may be 199$ for a 30lb jug at the retail stores. But at HVAC/R supply houses I can get a 30lber for 114$ out the door. I'm a EPA 608 universal certified and a NATE certified technician. I understand the transfer of heat and electricity well. And I'm no tree hugger but the ODP (ozone-depletion potential) of R-12 is just silly high. Not using R-134a is just plain wrong to me. The parts for 80-91 trucks are very cheap, and it is SO easy to just change it over, it really is. There is so much false information on why "R-12 is better than..." in automotive applications. Maybe if you had a 500 ton chiller for process cooling to negative 50 degrees you MAY have even a MINISCULE piece of ground to defend with any sort of logic. Even then a different refrigerant would be more cost effective and much better for the world in which we drive such badass trucks g.
I hope you can see my point, and understand. If not, help me understand why you ride the R-12 train so much?

 

because all my vehicles except for the 02 and 2014 trucks have it in them and it works just fine.
i can still buy it and will use it in them as long as i have them. i have seen way too many "converted" vehicles come into the shop for repair that ended up costing almost as much as the vehicle was worth because the conversion destroyed the air conditioning system.
there are way too many people out there that believe the parts monkeys that tell them "change the fittings and put this in"
then 6 months later bring the vehicle in with a dead AC and have kittens when you tell them it is going to cost over $1,000 to repair it.

 

Thanks for the $114 price comparison. It was an auto parts house where I asked. I'll ask at the Johnstone. I have an account and also am 608 certified but never worked as a tech. Have the 609 too but it is trivial compared to the 608.

It's not about ozone, it's all about money. After I learned that they detonated hundreds of nukes out west and a couple in Mississippi, I find it difficult to believe much of the environmental concerns of corporate America. They feed us industrial waste products, steroids, and choke us with innumerable airborne agents. How far from Japan does the Pacific glow at night? So, yes, I recover my old refrigerant but also know that when legislation can be used to guarantee profits, it will. We will be told anything but the truth.

The vent temp pic I posted was with R134. These systems need very little work to run it. It works every bit as well.

 

For the purposes of the forum, I thought (here I go thinking again). It perhaps, would be best to share what I know is useful information. If you let some DA mess with your HVAC system and play "mechanic", then you are in for trouble. Most "retrofits" are not done to standard. ALL air and moisture MUST be wrung out from the system, and ZERO leaks will be present if the proper procedure is a successes. Tools exist for these very purposes. If ANY ONE with a 1980-97 F series pickup has an R-12 system, it is exceedingly simple and rather cost effective to just swap it ALL out. Failing to remove all contaminants (R-12 oil, dirt, moisture, fillers, and bugs) will result in poor heat transfer. Like I said, RockAuto round 300$ and you can rest easy knowing you will get YEARS of around the clock performance from your HVAC system, and you did the world a favor and discontinued the archaic use of R-12...

 

"It's not about ozone, it's all about money. After I learned that they detonated hundreds of nukes out west and a couple in Mississippi, I find it difficult to believe much of the environmental concerns of corporate America." It's not just the U.S feeding us crap. The Montreal Protocol of 1985 sponsored the Vienna convention seeking international recognition for Ozone depletion. By 87, 191 different countries signed this, and steps were taken to try and do something. Anyhow that is not truck related and I have gotten off topic. At any rate, don't get ripped off for R-134a. The jugs at the supply house will NOT connect to strictly automotive gauge sets, an adapter is needed. Also, commercial refrigerant gauges will obviously not connect to quick disconnect R-134a ports. If you have your own commercial gauge set, CPS makes nice Q/D style fittings for them, that are also low loss. Nice vent temp by the way. I get a similar reading out of the vent routed closest to the evaporator here in Florida on 90+ degree days with 60%+ RH. I swapped out my liquid line for a copper section and a TXV by Four Seasons part #38608. It was a pain in the *** because I had to swet aluminum to copper and made flared the TXV in. It really helps for comfort when I'm idling in traffic.

 

You should post some pictures of your hybrid, modified system. Sounds interesting.

How do you match O-rings to automotive AC systems? Parts houses are no help with this. Dealerships can do it. AC shops can hand me the right stuff, if they'll do it. There must be a guidebook or something?

Tracking down leaks is still a challenge to me. Slow leaks are my weakest point with AC.

I think my van needs a blower motor. After a few hours on the road it feels weak. Got a favorite brand of motors?

I know about the international conventions but I also know that their universal language is money.

This will be my third 30lb R134 cylinder in 25 years, just for friends, family and my junk. So, ozone or not, it can't be good for us even if it feels good.

 

i use a "sniffer" to find leaks.
CPS LS790B for larger leaks,
and CRC aerosol leak detector for small leaks.

 

Next time I'm at my shop I'll take some pics, and probably take it apart and put it back together as a write up. The benefits to me, are worth the effort. Fixed orifice expansion devices are the technology of the past, even TXVs are ancient history. See a orifice tube is exactly that, just a measured hole. Now Ford did some justice and our trucks have suction accumulators, a protection device of sorts to prevent liquid floodback and introducing hydrostatic pressure onto our compressor components. Orifices rely on a difference in pressure to allow refrigerant to flow into the evaporator. No pressure difference? No expansion. The refrigerants job is to pick up heat. And although as a liquid it may absorb some BTUs here and there, the real work gets done with a change of STATE. When matter changes from a liquid to a gas, it can absorb a significant amount of heat. The reverse is when refrigerant goes from a gas to a liquid, it can reject this heat (Hopefully to an UNOBJECTIONABLE place ). These are the basics so to speak about air conditioning or refrigeration.
So, with that said the TXV, changes the game for our trucks. It is an internally equalized valve with a bulb. This bulb has a refrigerant in it as well, SEPERATE from the charge in the truck. This refrigerant charged bulb should rest tightly to the outlet of the evaporator, to "sense" the temperature of the refrigerant. Why? It does this for really one thing. To measure superheat at the outlet of the evap. Superheat is the excess of the temperature of a vapor above its saturation temperature at a given pressure. So with a superheat value of 1 we have just guaranteed ZERO liquid is present and all of our refrigerant is vapor. Which is critical for performance. The TXV will modulate slowly to let more or less liquid refrigerant in form the liquid line, and properly feed the evaporator an appropriate amount for ideal heat transfer. This equates to better vent temps at idle, and low load conditions where with a fixed orifice, no such modulation can take place...
How to find small leaks? I use an electronic leak detector. It is very expensive, as my trade is ensuring heat goes where we want it to for commercial refrigeration. If you do not have a leak detector, next best thing is tried and true soapy bubbles. I go to the dollar store and get bubbles, ya know for little monsters (kids). I mix that with equal part of Dawn dish soap and water and put it in a sprayer. Put the truck in a garage if you can. Spray all points suspect of leaks, and looks for bubbles to shoot out. Spray a non leaking piece of metal first so you know what your solution looks like without a leak for reference. This is how I've done it for the last couple years. At 24 summers old, I still got plenty of that learning to do...
What motors do I use? For my Fords, only original blowers from junkyards. I DESPISE the local part stores products and avoid them like the plague whenever possible. Sounds like you may have a small vacuum leak to a blend door actuator. My truck would occasionally blow very weak, and it was a crack in the vacuum line to the actuator.
O-rings? I feel ya on that. With a retro-fit to a refrigerant that requires a incompatible lubricant for the old system, all these suckers MUST be changed for the sake of the compressor gods. I get mine at the AutoZone, get a pack of around 50 or so. And Advance Auto will NEVER tell most people, but behind the counter of my store there are 12 pull out drawers with nothing but metric and SAE O -rings. Green and black. Might try and ask your local AA store.
And I get it, R-134a is not perfect, but it is a SCIENTIFIC FACT, not opinion, or speculation... That it is WOLRDS more Ozone friendly than chlorinated refrigerants such as R-12. The fact is in the chemical composition of the refrigerant. Scientists that have NOTHING to do with the EPA or big corporations have studied this. Chlorine in R-12 or Dichlorodifluoromethane, or Freon 12... Whatever you want to call it is a O3 KILLER. The Montreal Protocol, and the Vienne Convention was not in the game for the money. Out of the 191 countries that signed it, some of them don't even have central A/C for over half the population. So, if it really is about money, you tell me who profits? Sure ain't the refrigerant companies if you break it down. They made money off R-12. Why did they want to spend millions changing their whole process and tools for R-134a production? I don't trust the U.S government very much, but I know this is one of those actions where interests other than itself were taken into account.

 

I've been posting in this forum and other forums for many years about subcool, superheat, sensible heat and latent heat of evaporation. It doesn't go over well.

I also have tried to get people to charge these orifice systems by cycle time, doesn't go over well. Mentioned to charge a orifice system by superheat and an expansion valve system by subcool. Doesn't go over well.

Posted about why moisture in your system is your enemy. Doesn't go over well.

It's hard to get people past the "more is better" way of thinking.

I've said why a system won't blow freezing cold air immediately after it has been sitting in the sun on an asphalt parking lot all day. Doesn't go over well.

My 1979 pickup was an expansion valve system. Not sure exactly when they changed to the orifice system. At some point the orifice system got a high pressure switch. I think it was with the change to R134.

Somewhere I read that 1969 was the first year that half of new American cars were delivered with AC. Things changed fast.

Patent expiration was offered as the justification for refrigerant changes. Never looked into the facts too far.

 

Most people are under the delusion that more is better. And most people will ever understand that your cars AC can't make the cab go from 120+ degrees to 70 instantly. I like finding ways to make the AC in my truck more efficient. The 74809 Four Seasons coolant bypass valve is a great addition too. I am taking the cab off my truck soon for some minor rust repair and some serious customization. I'm going to use thin fiberglass duct board to insulate my floor, cab corners, rear of cab, and roof.
I also frequent my local junkyard to see if I can score a rooftop AC system. I have a York210 in place of where my smog pump used to be. Was gonna do onboard air for tires, but never researched the fittings for the tires beforehand. Needless to say that cheeseball plan fell through quick. I would however like to hook it up to a rooftop unit and hook that baby up to my topper... I