Nashville TJ's Build - Continued

NashvilleTJ said:

I'm heading out to Sand Hollow with the boys in May. And what can't you do without at Sand Hollow in May?

Tons?

No.

Fodeez?

No.

Hemi?

No.

A/C?



'Xactly.

I figured I'd better test it out after the long winter, so after polishing off the trailer mod yesterday I took it out for a spin, and sure enough - no A/C.



Quick check, and I had not just low pressure in the system, but no pressure in the system. I run die in the system so finding leaks is usually easy under ultraviolet light. The only place I saw a bunch of die was the Low Pressure Shrader valve. Great. Easy fix. Swapped out the valve and hooked up my gauges and vacuum pump.

No joy. After pulling 30 Hq on the pump and shutting it down - it dropped to 0 in about 5 minutes. So, big leak somewhere.



So, off to find a big leak. To do this on a discharged A/C system, what I do is attach the compressor, put in 50 psi of air, go to town with a spray bottle of soapy water, and look for bubbles. And, I found them...

The first was right in my face - the Low Pressure switch on the accumulator. Easy fix with two new o-rings.

View attachment 672863

The next was less obvious, and I had to remove the accumulator to see it. I didn't get a bubble shot, but the connection at the condenser basically filled that entire space with bubbles. Definitely the big leak.

View attachment 672865

Two more o-rings, and I double checked everything else. Those were the only two leaks I could identify.

So I pulled vacuum again last night, evacuated it for about an hour, shut things down and let it sit.

And this morning - still 28 Hg after 12 hours. Hopefully, that nailed it.

View attachment 672866

20 oz of R143a later, and we're back in business.

View attachment 672868

Click to expand...

Wait, Jeeps have AC??!

Edit: I guess I can stop stressing about finishing my build before then. I'll just ride with Jeff.

Woodrow said:

Wait, Jeeps have AC??!

Edit: I guess I can stop stressing about finishing my build before then. I'll just ride with Jeff.

Click to expand...

Stay out of my seat!

Jeff - I assume your system uses R-134A, like the stock system? Are you aware that R-134A is in an EPA phase-out? That means EPA has started reducing the allowable production, and when that happens, prices skyrocket. Here's the phase-out schedule:


In other words, the manufacturers are already at 60% of the baseline production, and in 2029, that drops to 30%. Prices rise with each step down because units in use get older and more maintenance is required, but supply is restricted. They don't take the limit to zero, though. It stops at 85% reduction. It'll be interesting to see if they eventually do take it to zero. They did that with R-12. Nowadays, you can still find R-12, but it's either new, old stock or recycled. They haven't made any new stuff in decades.

I do my own A/C work on my cars, so I stocked up on R-134A for my cars in early 2024 and R-410A for my home system (it's on the same phase-out schedule) to insulate against these supply restrictions. I don't do work on my home system, but my home A/C guy is okay with me supplying refrigerant.

If you're not aware of this, and you don't keep a lot of refrigerant at home, you may want to stock up. When R-12 was phased out completely, the price shot up to over $100 per pound. My hope is that I bought a lifetime supply of both at $11/pound...

sab said:

Jeff - I assume your system uses R-134A, like the stock system? Are you aware that R-134A is in an EPA phase-out? That means EPA has started reducing the allowable production, and when that happens, prices skyrocket. Here's the phase-out schedule:
View attachment 672869

In other words, the manufacturers are already at 60% of the baseline production, and in 2029, that drops to 30%. Prices rise with each step down because units in use get older and more maintenance is required, but supply is restricted. They don't take the limit to zero, though. It stops at 85% reduction. It'll be interesting to see if they eventually do take it to zero. They did that with R-12. Nowadays, you can still find R-12, but it's either new, old stock or recycled. They haven't made any new stuff in decades.

I do my own A/C work on my cars, so I stocked up on R-134A for my cars in early 2024 and R-410A for my home system (it's on the same phase-out schedule) to insulate against these supply restrictions. I don't do work on my home system, but my home A/C guy is okay with me supplying refrigerant.

If you're not aware of this, and you don't keep a lot of refrigerant at home, you may want to stock up. When R-12 was phased out completely, the price shot up to over $100 per pound. My hope is that I bought a lifetime supply of both at $11/pound...

Click to expand...

I didn't know 134 was being eliminated, guess I need to buy some for the shelf. Are there no replacements or substitutes out? I know some in the old car world with R-12 systems will run propane.

BlueC said:

I didn't know 134 was being eliminated, guess I need to buy some for the shelf. Are there no replacements or substitutes out? I know some in the old car world with R-12 systems will run propane.

Click to expand...

None that I know of. It's a typical, "let's pass a law and the market will figure it out," government mandate - like our awesome gas cans we can buy now.

R1234 is the newest i think.

John Cooper said:

R1234 is the newest i think.

Click to expand...

Technically, it's R1234yf, and it's slightly flammable - the first vehicle refrigerant that is. My wife's car has it, and it doesn't cool nearly as well. On a hot Texas day, it takes about 15 minutes for the temperature in a hot car to get comfortable. It's ridiculous. I bet @freedom_in_4low can add a lot more details, since he's an HVAC engineer. He's probably forgotten more than I know, as they say.

Edited to add: R1234yf is incompatible with systems designed for R134A, so it's not a substitute or direct replacement. If you want to switch from R134A, I think everything in the system needs to change.

sab said:

Technically, it's R1234yf, and it's slightly flammable - the first vehicle refrigerant that is. My wife's car has it, and it doesn't cool nearly as well. On a hot Texas day, it takes about 15 minutes for the temperature in a hot car to get comfortable. It's ridiculous. I bet @freedom_in_4low can add a lot more details, since he's an HVAC engineer. He's probably forgotten more than I know, as they say.

Edited to add: R1234yf is incompatible with systems designed for R134A, so it's not a substitute or direct replacement. If you want to switch from R134A, I think everything in the system needs to change.

Click to expand...

I just know we saw our first class 8 truck about 3 months before I retired in September with R1234yf. I am almost positive it can't be used with any AC machine that could do previous Freon.

I think RobinAir said it takes it's own specific machine.


Maybe @freedom_in_4low can help us.

Edit: I think the .Gov is purposely doing this also.

NashvilleTJ said:

I'm aware of the phase out Scott, but good call on stocking up a bit. I was actually looking at theR1234yf this morning when I picked up the R134a. I did a quick bit of research - sitting on the floor of the Advance Auto - and confirmed that the "yf" stuff is not compatible with the "a" stuff. Apparently, different seal requirements, etc.

As I understand it, the driver is environmental - no improvement in efficiency, energy capacity, or anything else. Hence EPA, I guess.

Damn you, Big Refrigerant!



And big surprise - The "a" stuff was about $15 for 12 oz. The "yf" stuff was about $30 for 12 oz. So, price is going way up either way...

Click to expand...

I think I remember Rick saying it's ( R134a) getting harder and harder to even find in WA state.

reddvltj said:

I think I remember Rick saying it's ( R134a) getting harder and harder to even find in WA state.

Click to expand...

Illegal to sell in WA...

NashvilleTJ said:

I can, ahhhh, get you some for a "reasonable" markup...

Click to expand...

I've gotten a good stash every time I go to ID...
I'll buy some more on this trip.

John Cooper said:

I just know we saw our first class 8 truck about 3 months before I retired in September with R1234yf. I am almost positive it can't be used with any AC machine that could do previous Freon.

I think RobinAir said it takes it's own specific machine.


Maybe @freedom_in_4low can help us.

Edit: I think the .Gov is purposely doing this also.

Click to expand...

NashvilleTJ said:

I'm aware of the phase out Scott, but good call on stocking up a bit. I was actually looking at theR1234yf this morning when I picked up the R134a. I did a quick bit of research - sitting on the floor of the Advance Auto - and confirmed that the "yf" stuff is not compatible with the "a" stuff. Apparently, different seal requirements, etc.

As I understand it, the driver is environmental - no improvement in efficiency, energy capacity, or anything else. Hence EPA, I guess.

Damn you, Big Refrigerant!



And big surprise - The "a" stuff was about $15 for 12 oz. The "yf" stuff was about $30 for 12 oz. So, price is going way up either way...

Click to expand...

Did somebody say my name 3 times in a mirror?

Yep, it's all environmental.

Back in the 90s it was all about ozone depletion, so they banned CFCs like R12 and R22 and we went to 134a and 410a which were HFCs and don't deplete the ozone layer but they have global warming potentials thousands of times higher than CO2 which is what everybody thinks of as the big bad greenhouse gas. So the next generation is HFOs and there's a dozen or so common ones.

1234yf is a low density and low pressure but decently efficient gas much like 134a and R12 before it, so it's become pretty popular in automotive. It's also ridiculously expensive so it hasn't become as popular in other markets that require larger charge amounts. 1234ze has similar properties and costs 30% less so it's more common in the other segments that like low density/low pressure gases - HVAC rotary screw compressor chillers. Neither gas is common in mainstream residential and light commercial HVAC or refrigeration because low density means the compressor has to have a lot of displacement which isn't well suited to scroll compressors and they're not common in refrigeration because the pressure gets too low to be easily controlled. In resi and light commercial you see more 454b and r32 because they're more dense.

What's almost hilarious at this point (having watched a 30 year game of whack-a-mole) is that the HFOs will probably be banned in another 10 years because they break down into PFAS "forever chemicals" so the industry is moving toward natural refrigerants. Propane is almost a drop in for R22 but it's flammable so it requires leak detection and mitigation if it's in occupied space in amounts more than a few hundred grams (in the US...Europe is less restrictive). Ammonia is really efficient but it's also toxic and it can't be in contact with copper so you need welded steel piping and the compressors have to be open drive or have aluminum windings, and CO2 is really high pressure and efficiency goes to crap if you're south of Canada. The only known is that systems are only going to get more expensive.