New refrigerant for HVAC.

Mustangman

Everytime the fed gets involved in our trade, we end up paying. I didn't see where anyone mentioned it but, ductless units will using R32 and split systems R454B. So New gauges for the techs, re-training because both new gasses are flamable, stock more types of refrigerant, Re-label trucks for flamable gas. They claim that the pressures should run lower than R410A. As for the flamability, it not what you think. It does.t catch like gasoline. Its 8% flamable. If you spilled some and threw a match on it, it won't flash and burn. It will burn but at a slow rate.
Last refrigerant change was a nightmare. The pressures were so high coils started leaking. They didn't tell us much about 410A. I expect the same with these two refrigerants.
Add on top of a gas change, the SEER rating system changed to SEER2. Ever since SEER was a thing ((Seasonal Energy Efficiency Ratio) they tested the equipment at .10 static. Thats all fine and dandy but we run a .50 static in our ductwork. Kind of screwed up right? So all those years I designed ductwork with a .50 static were messed up? Hence SEER2, HSPF2 ( Heating Season Performance Factor ) and a few other rating changes comes along to save the day.
Oddly enough the SEER2 Runs just like the SEER1s
Good Luck

pecmsg

The coil leaks were more a result of the new DOE requirements for energy usage. Make the copper thinner than rifle the interior.

The bad X-Valve issues were a result of a rust inhibitor used in the manufacture of the compressor shell that reacted with POE oil.

Currently supermarkets are going to CO2 systems or R-290 Self Contained cases.

ChrisJ

I'm assuming R32 is still using POE?

pecmsg

ChrisJ said:

I'm assuming R32 is still using POE?

I believe PVE

EBEBRATT-Ed

Just put a roll out switch on the evaporator coil

Mustangman

R32 and R410A both use POE oil

Mustangman

Carrier, whom everyone follows, is switching to R454B as their refrigerant in split systems. More good news... ductless are switching to R32. Both are considered mildly flamable and are in the A2L class. It won't flash off or burn like fuel. But it will burn if the conditions are right. Think about this. We are all going to have to be trained to handle and transport R454B and R32. Do our trucks have to have flamable stickers? We get to haul around another 25lb canister of refrigerant. R32 has been in use around the world as the refrigerant for ductless split systems. I can see the move to R32 as its been in use for many years. The bugs are worked out. R454B... who knows.
Steve

ChrisJ

Mustangman said:

Carrier, whom everyone follows, is switching to R454B as their refrigerant in split systems. More good news... ductless are switching to R32. Both are considered mildly flamable and are in the A2L class. It won't flash off or burn like fuel. But it will burn if the conditions are right. Think about this. We are all going to have to be trained to handle and transport R454B and R32. Do our trucks have to have flamable stickers? We get to haul around another 25lb canister of refrigerant. R32 has been in use around the world as the refrigerant for ductless split systems. I can see the move to R32 as its been in use for many years. The bugs are worked out. R454B... who knows.
Steve

Hazmat placards are required for loads of 1001 pounds and higher.
Are you considering transporting 1001+ pounds of refrigerant in a van?

pecmsg

Do you have the placards for your torch?

jumper

Know what? H20 is excellent for A/C.
Not for other sorts of refrigeration.

ChrisJ

jumper said:

Know what? H20 is excellent for A/C. Not for other sorts of refrigeration.

Can you please provide more details on that?

PRR

Old refrigerants...
Scientific American, December 1935

Five years ago Thomas Midgley, Jr. , of the General Motors Research Laboratories reported the discovery of the nontoxic refrigerants di- and trichlorodifluoromethane and predicted that the application of these compounds to air conditioning would greatly broaden the scope of that industry.
The prediction has been verified. The total air conditioning in use in the US. is now more than 16 times what it was in 1930!

Di/Trichlorofluoromethane are also called freon-11/12.
Midgley also worked on tetraethyl lead (leaded gas), which led to cases of lead poisoning, hallucinations, insanity, and 13 deaths.
https://en.wikipedia.org/wiki/Thomas_Midgley_Jr.
"In the late 1920s, air conditioning and refrigeration systems employed compounds such as ammonia (NH₃), chloromethane (CH3Cl), propane, methyl formate (C2H4O2), and sulfur dioxide (SO2) as refrigerants."

ChrisJ

@PRR

I have both methyl formate and sulfur dioxide in use in my kitchen. 

They work fantastic.

jumper

For many comfort applications 60° evap temperature can be okay. 60° evap lift to 120° condense require compression ratio about 6. That is doable and I built prototypes with various compressors. Problem is that system has to be absolutely hermetic. Machine is in vacuum condition. Any air or other noncondensible wrecks performance and efficiency.

For a cascade setup; a lesser compression ratio, which makes things easier, water enables condensing CO2 refrigeration. Refrigerant business suffers.

ChrisJ said:

jumper said:

Know what? H20 is excellent for A/C.
Not for other sorts of refrigeration.

Can you please provide more details on that?

ChrisJ

jumper said:

For many comfort applications 60° evap temperature can be okay. 60° evap lift to 120° condense require compression ratio about 6. That is doable and I built prototypes with various compressors. Problem is that system has to be absolutely hermetic. Machine is in vacuum condition. Any air or other noncondensible wrecks performance and efficiency. For a cascade setup; a lesser compression ratio, which makes things easier, water enables condensing CO2 refrigeration. Refrigerant business suffers.

jumper said:

Know what? H20 is excellent for A/C. Not for other sorts of refrigeration.

Can you please provide more details on that?

That's 70% RH at 70f.

Yuck.

jumper

>> That's 70% RH at 70f. Yuck.<<

Is 70% RH that yucky?

Depends on circumstances. Unconditioned spaces are far more pleasant @ 70° when outside is in nineties. Then there's hot dry places that don't require dehumidification.

One can chill water to lower temperatures with H2O refrigerant but condenser does get bulky. Future I think is going toward CO2 refrigerant. Question then becomes transcritical versus CO2/H20 cascade.

ChrisJ

I aim for 70-72f and below 50% in my house and I have it setup so above 50% it slows the blower down.  Sometimes if it's really hot out I'll raise it to 55% to keep my sensible cooling higher.


 60% and above definitely feels nasty.

archibald tuttle

this was a great thread so, rather than make a new one to discuss flammable refrigerants, thought I would reboot it to say that I am hoping this discussion can take place in person in Orlando at the AHRExpo. Without getting too political so posts get vanquished, I think I can safely gleen some cynicism in this thread that industrial engineering decisions are becoming, instead, political.

Besides running into you in the aisles I'll be hosting an informal breakfast for any wallys at Keke's Breakfast Cafe, 7512 Dr Phillips Blvd in Orlando the morning of Tuesday, Feb 11 at 8 AM (that's about a 3 mile Uber from the convention center. And getting you up early Tuesday is just to insure you don't get too hazy the night before at the Hazen White Party :-). I'm passing out invitations to the breakfast stenciled on shirts this year so you wear the gospel of RBOOM, Raise the Boom , cause refrigerants that go boom could be a boon for the industry, the economy and the environment.

This A-3 issue is at the center of my agenda. I too am kind of tired of going to industry events to sit in panels that tell us EPA says "jump" and we are simply supposed to respond "how high". It isn't that I don't want to know what the rules are; but these events are a missed opportunity for regulators and designers to incorporate the experience of field techs who install and service this equipment into their R&D.

I don't view the whiplash of refrigerant obsolescence as a conspiracy so much as a confederation of dunces. Yes there are industry players who have patent interests, and there can be regulatory capture. But even down to the field level, many have simply gone along with the system as it suits their own rentseeking. Forgetting the current (perhaps somewhat merited) obsession with heat pumps, who thought it was a good idea for utility regulators to spend our money subsidizing the replacement of perfectly good relatively generic cast iron boilers with shorter life span highly proprietary condensing boiler installations that were rarely if ever likely to condense given system designs? But a lot of plumbers got a lot of work out of that.

My take is we should forget this halfway pregnant A2L thing and just go A3, or at least open up that possibility and get some field work going with the naturals. Yes we would need higher charge limits, and maybe system design to better prevent release, e.g. material thickness in heat exchangers should contemplate longevity over absolute efficiency. But on the advantage side for the natural A3s are some really low operating pressures (butane and pentane condensing at like 30 and 70 psi respectively at 125 º F that make flare field connection potentially far more reliable than the high 300s or 400 with 410a. And I think they are compatible with the gasket material in the latest press technology, but don't quote me on that. They are compatible with the less hygroscopic more foregiving traditional mineral oil; meaning that evacuation is less of a headache because there is less moisture trapped in the oil and my understanding is these systems in operation are a little less sensitive to trace moisture. And they exhibit decent efficiency modestly offset by their relatively low weight to volume.

Propane and Butane (inc. isoButane) are in use in at higher charges in Europe and India (and probably everywhere else in the world too, those are just reports I noted) and we simply are not seeing accounts of household explosions or conflagrations related to this. And Pentane strikes me as needing more investigation with extremely low operating pressures. Propane has been favored so far for efficiency and drop-in similarity to R22, but the industry has hamstrung itself already by focusing on single favored indicia instead of looking at the overall utility of refrigerants. Ironically, I like Propane less because of it's similarities to R22 especially operating pressures which I am far more cognizant of with A3 refrigerants. Sure, easy to contain with good practice but I'd always rather be under 100 PSI than under 300 PSI–nevermind that my flare practice seems to be keeping the 400 PSI of 410a in check (albeit none of my systems have been in service long enough to see if I'm going to beat the EPA estimate of 7 year refrigerant life.)

In this habit of focusing on a single refrigerant characteristic, the first shakeup was Ozone Depletion Potential. And A3s were ruled out of the that transition in the US based on flammability, again focusing on a single characteristic. So they handed us refrigerant that was supposed to solve the high regulatory barriers placed on R22 by the Montreal Protocol but now they are freaking out about Global Warming Potential and regulating R410A almost as viciously as R22. And it appears not to have occurred to them that moving to refrigerants with a third higher operating pressures might lead to more refrigerant loss! Never do they seem to have really taken into account what refrigerants can be most efficiently maintained by the existing and upcoming core of field techs, or–god forbid–the homeowner.

Speaking of the homeowner, the systems I'm seeing with low refrigerant or contamination only a couple years in are going to lead to consumer dissatisfaction–but of course they don't really seem too worried about whether the consumers are happy either. Apparently it didn't occur to anyone that consumers vote. I'm not holding forth on the wisdom of their choices, Erin, just that these peccadillos can matter politically.

I'm not here to diss taking cognizance of ODP, GWP, COP, flammability, or toxicity for that matter. I'm suggesting that no one of these should take such precedence that poor performance on other measures is ignored–and the list of characteristics driving refrigerant choice should actually be significantly longer than that. We probably should have stuck with good field practice with R22 longer–given that it has 2 orders of magnitude less ODP than R12–if we didn't have a good replacement. Instead the industry seems to have ignored the unintended consequences of focusing so narrowly when there are multiple factors, and multiple constituencies besides manufacturers and bureaucrats that should be taken into account.

So join me in RBOOM, Not that I'm out to subsidize these notions with everybody's utility rates. I would just like to get to where charge limits on par with the couple of 1 lb throwaway cans of propane probably sitting in your basement are not thought to be off the table for discussion. Even the otherwise regulatorily retentive europeans seem comfortable with that, why not America. Or join me and tell me why I'm wrong.