"Flammable" Refrigerant Facts for Residential HVAC

In this training class, Bryan Orr from HVAC School provides key facts and information for HVAC technicians about the transition to mildly flammable A2L refrigerants like R-32 and R-454B being adopted for residential and light commercial systems. He covers the reasons behind the phase-down of higher global warming refrigerants like R-410A, the differences between A2L refrigerants and propane, similarities and differences compared to R-410A, changes to equipment and components, best practices for handling mildly flammable refrigerants safely, evacuation procedures, leak testing, and more. This is a must-watch for any residential HVAC tech getting ready to work on new A2L systems in the coming years. Bryan dispels misinformation and fear-mongering around these new refrigerants while still emphasizing the proper precautions that should be taken.
Buy your tickets or learn more about the 6th Annual HVACR Training Symposium at hvacrschool.com/symposium.
Read all the tech tips, take the quizzes, and find our handy calculators at www.hvacrschool.com/ or the HVAC School Mobile App on the Google Play Store (hvacrschool.com/play-store) or App Store (hvacrschool.com/app-store).

[@brianmcdermott2430]

Great info. Bryan. Thank you.

[@tedbell4416]

R-22 "significantly lower pressures" , yeah and equipment that lasted 20-30 years plus

[@youarethecreator1]

100% correct

[@cliffanderson7544]

Been doing hvac 16+ years now. Still have a 23 year old r22 system that runs perfect. I will run it until I no longer can!!!

[@whofixeditanyways]

@@cliffanderson7544 I just serviced one from 1975. Someone cut the blower cap out and it has been running without a cap for I don’t know how long. The condensing unit is from 1995. Still chugging along.

[@marknaravas318]

The house I grew up In had an American standard that went 35 years till it blew a condenser. The Heil replacement only made it 7 years.

[@tristantimmonstt]

Service three 1995 Lennox 5 ton condensers at a shop and all have the original compressors. They don’t make em like they used to..

[@youarethecreator1]

HONEYWELL EXPLOSIVE ORDNANCE DISPOSAL (EOD) SUIT FOR HVAC TECHNICIANS AND INSTALLERS. $1899.95

[@joez.2794]

*MANDATORY

[@chucksmoko5348]

Explosive vs flammability are not one in the same.

[@timrob0420]

You are truly a blessing to this industry

[@s.j.5850]

You really know your stuff Bryan. We appreciate you explaining the significance of the new refrigerants that will become the industry standard.

[@bikerbobcat]

I've spent the last couple of years doing commercial almost exclusively and only heard a little about this changeover, so was very nervous, but this video is very helpful. Thanks so much for great information and presentation, as always.

[@timbrown9305]

A friend of mine is a chemical engineer that lived through 40 years of these changes. He said it is NOT for the environment and never was. Twisted data on the effects of these chemicals was done deliberately. He said these changes keep the industry selling new equipment and the chemical companies like the one he was in management for, making new product.... He was very high up in a company you all would recognize. Our government is not what you think it is.

[@GilmerJohn]

BINGO. Back when the Ozone problem was invented, R12 cost $1/lb in retail consumer sales. The stuff was used, as an example, for BB "machine guns" and to chill glassware for mixed drinks and so advertised on TV. Why so cheap? Off patent. Funny thing, the replacements were only manufactured when the maker paid a license fee.

[@footiefan51]

Nope.

[@joez.2794]

@@footiefan51 In the the 30 years I've been running my R22 unit, a typical newer system would've been replaced 3 or 4 times. How could the manufacture and disposal of all those POSSIBLY be better for the environment? "Efficiency?" If the new stuff is so much more efficient, how come 15,000BTU is still the max for a 15A circuit? You could get a 15K BTU window A/C that drew 13A in 1985. You'd think we'd at least be up to 18K BTU by now??

[@Carlossoto-rg5hh]

Damn , I'd like to hear what your friend has to say. That's wild to hear as a young HVAC technician. Thanks for sharing.

[@antonioharris-g.a.-hvactec4997]

The two teachers taught well as usual.The class was interesting to learn from.The best class to teach with no mental health distractions with skybox proofreading.#GreatJob!

[@scottritchey7492]

I'm v. To

[@joez.2794]

I'm in IT - watched the whole thing. You're a great presenter.

[@brewaz]

Your presentation is very informative and easy to understand thank you for sharing!

[@InsideOfMyOwnMind]

This looked like perfectly done presentaion. It would be facinating to see some of the notes that the people who were there took.

[@acservicetools]

Good job Brian. The regulations is almoust the same in Europe to. Love your videos. Learn a lot from . Ciao

[@joshuaricks7730]

55:00 You will eventually will have to have some type of mitigating active system in storage areas with sensor and a means to ventilate.

[@garypoplin4599]

32:03 We used nail plates on wooden studs where NM cable is run in the wall closer than 2 3/4” to the wallboard (I think that’s even in chapter 70 of the NFPA code).

[@juanarboleda]

Master Class, Thank you 🙏

[@danidoom666]

Thanks for making these videos!

[@frankblankenship3026]

Great presentation, thanks

[@youarethecreator1]

Here is some scientific information that should be taught: A2L laboratory testing was not within the stoichiometric combustion range of the A2L Gas. This gas is combustable in concentrations of less than 13% at room temperature and normal atmospheric pressures. See the MSDS: "Flammable gases, Category 1 Gases, which at 20°C (68°F) and a standard pressure of 101.3 kPa (14.7 psi): (a) are ignitable when in a mixture of 13% or less by volume in air; or (b) have a flammable range with air of at least 12 percentage points regardless of the lower flammable limit.

[@mahmoudalimardani5490]

Thanks a lot for everything

[@Studentofhvac]

Excellent!!!

[@Ryansroga-wm6pj]

Pretty cool thanks for sharing

[@keithb2696]

Has anybody noticed a lot of 5 to 10 year old evap coils that are leaking. Especially the aluminum coils. Are they going to start building the equipment better?

[@Damien567777]

higher pressure refrigerant (r410/R32) reducing equipment life and then race to the bottom on price means manufacturers compromising on copper quality.

[@smacleod69]

No, manufacturers are not building equipment better. New coils are micro channel.

[@GilmerJohn]

Because of the anti-R12 histeria, most consumer aerosol cans use flammable propellants. Even/especially food products often use flammable propellants. Inhalers are much more expensive and dangerous. But that's OK.

[@joez.2794]

I just can't get over the fact we could've skipped R410A altogether, and even by THEIR measure the environment would've been better off. It makes more sense to just go back to R-22 at this point, and we know it.

[@tobiaszkucharczyk8595]

10 years ago r410a

[@blaub4r]

we are already on A3 :D... welcome to the new world ...

[@chucksmoko5348]

The SCOTUS RULING striking down Chevron Deference may affect EPA powers going forward.

[@darylfortney8081]

Can’t wait for this transition to complete so I can finally upgrade my r-22 seer 10 unit from circa 2000. Skipped 410a entirely 😅

[@darylfortney8081]

Sounds like a guaranteed and great investment just stocking up on 410 right now. Might sell off some stocks and buy a warehouse of 410 tanks.

[@darylfortney8081]

You forgot to mention no smoking while working on a system

[@melllvar4262]

35:44 Caddie Shack!🤣

[@jesseanderson4612]

Is there going to be a rule about sitting the condenser 10feet away from the home?

[@HVACRTECH-83]

Lol no

[@youarethecreator1]

Body Armor and helmets will be required

[@jk-mm5to]

Would it be too much to ask for you to issue notifications for upcoming videos?

[@brenninwatts1249]

The part about not unsweating anything and to cut it out because of residual refrigerant in the lineset. Does this apply for example if I am changing a filter dryer, compressor or evap coil and I have the system recovered and shraders pulled and have nitrogen flowing? I would thing the nitrogen would have pushed any residual refrigerant out including displaced the oxygen to keep anything from igniting.

[@Elisummit845]

At 32:12 we call it nail plate.

[@adambarrett3296]

You're not supposed to sweat the filter drier off but it's okay to braze it back on?

[@HVACS]

Yes, you are flowing nitro at that point You could flow nitro while you unsweat but pulling apart under flow is still not a great idea

[@borshardsd]

Ty for tge content! Our country is in a sad state if Brian has to say "not getting political " while stating facts

[@kennethbubser9601]

Can we sue epa for all the different refrigerants we breathed in. I got r12 22 410a 134 407c in my lungs every time I disconnect my gauges. My lungs are running on mixed refrigerants. Thanks Epa

[@russoft]

not gonna lie, I was angered by this change and worried about the flammability. But I'm also not an expert in this field so thanks for the education! As a consumer, do I have to worry about lower reliability and higher costs (electricity, refrigerant, equipment) than R-410A? End of the day, that's what I care about

[@smacleod69]

You will have to worry about the reliability. I'm not optimistic at all with the new equipment. Most of the new units are designed using micro channel coils that are known for leaks. make sure you have 10 year part warranty and longest labor warranty possible on new equipment. Every cost is going to be put on the consumer.

[@EduardoBurgosRecess]

theres another Channel call Mickey Pipes his making a big deal about this jaja im glad i came here to double check

[@4wardnthought234]

If the insides of my vents are sweating, that air space is already sealed and dehumidified. The entire system is in the crawls space (4 ft high cinder block walls, mostly closed with several vent openings). Should I encapsulatr the crawl space and run a small window AC during summer to cool that air slightly? I'm in North Alabama, very muggy and hot.

[@smacleod69]

encapsulate and dehumidify Your crawl space has high humidity issues. And if your ducts are sweating on the inside. your air is moving too slow and colder. Do you have a 2 stage system or an invertor?

[@4wardnthought234]

​@@smacleod69 Nope, single stage. Trane XR14 2.5 ton. Split unit, handler is in middle of house in crawl space, compressor outside. All ducting is in crawl space. It was installed 2 years ago, replacing the original heat pump from when the house was built only 16 years ago. The ducting was in good condition so we just used that. On closer look, I don't see the vents sweating, no sign of moisture on any of the vents or duct interior and it's 90 degrees outside, while I keep the inside 69. I may have been incorrect about the sweating, the service man said there was moisture getting in the system somehow because of the signs we were seeing. While some of the registers still look brand new, a few have rust spotting on the inside surfaces and those also have heavier dust buildup inside the ducts. One of them is so bad the register is nearly engulfed in rust and the inside of the galvanized duct is getting rust spots. How could some look brand new while the others are rusting? If it's not sweating from cold air on warm surface, what could it be?

[@smacleod69]

@@4wardnthought234 69 degrees? Thats one problem. When your new system was installed, did you keep the original duct system? And if so, were the boots sealed inside with duct sealant? Are the boots insulated up to the floor in the crawl space. You can use spray foam around the boots to seal.

[@4wardnthought234]

@@smacleod69 Why would 69 be a problem? Don't worry about what temp people like in their house, that's not your concern. Tell them how to get the air quality they want. My followup reply answers 2 of your questions - we kept the original ducts and they are sealed from end to end with ¾ or 1 inch thick fiber type insulation and the metalized wrap. The original installer did a quality job, I haven't seen any serious short cuts. All the joints are sealed with metalized tape, even the connection to the floor. Make sure you read my followup reply - I'm not sure that it's moisture. Since my first comment I looked closer and couldn't find any moisture. The seasonal service guy just said he thinks there's moisture in the system. But he was fairly new. He said that because a few registers that have significant grey/black deposits on the underside and in the first foot or so of ducting. And those registers are starting to rust in small areas, while the other registers and the inside of their ducts still look brand new. It's definitely not Stachybotrys, I've had that before, I know what it looks like. I don't even think it's regular mold, it just looks like dust buildup, but it's not evenly spread like dry dust. It's more like splotches or bundles, like dust that accumulates on water droplets. One register is very bad, literally covered in rust. And the gunk buildup in the duct is very high. But it's like dry dust and cobwebs. Maybe it was wet before at times, but I found no moisture and it 90 degrees today.

[@smacleod69]

@@4wardnthought234 First of all, Ive been in this industry a long time. I know what I am talking about! 2nd, Most of my calls are from people who have tstats set below 70. I will tell you how it is! It will make the system work harder. 3rd, that low of temp is having the sytem run longer, sending much cooler air through your ducts and if your air flow is set right and moving slow can cause issues the one your facing now. 4th, if your duct work is incorrect for the 2.5 ton system you have now, plus duct an R4 instead of R6 or R8, that is contributing to the problem. 5th, if you have dust in your ducts, dirt captures moisture and can create problems. 6th, have your a proper service tech do a static pressure test done on your system! 7th, have your ducts cleaned. Get a thermal scan done of your house. Find out the R value of your duct work. And lastly, you can have whats called a "Duct blast test" done to find out the percentage of duct leakage.

[@mikev.1034]

👍👍

[@trevmint5615]

Is that making me sound old? Oof! 😂😂😂

[@Hvacrpro123]

I put a flame out with r32

[@jerrylockhart3069]

I’ve seen 2 ton infinity systems with 11 pounds factory charge what’s the total charge of 16 1/2 , 😮17 pounds that’s crazy

[@Guyhakverdi]

I HAVE FEW QUESTIONS; 1.WILL THIS REFRIGERANT REQUIRE DIFFERENT COILS? CAN WE USE CURRENTLY MANUFACTURED COILS BY JUST CHANGING PISTONS OR TXVS? ARE THERE PISTON CHARTS AVAILABLE FOR R32? 2. DIESEL EFFECT MEANS EXPLOSIVE, IF SOME INCOMPETENT TECHNICIAN INSTALLS AN AC WITHOUT PULLING A VACUUM AND CONDENSER GETS REALLY DIRTY UNDER A DECK WITH PRESSURES 500-600 (I HAVE SEEN IT MY SELF 650PSI ON MY GAUGES R410 WAS OVERCHARGED.) IMAGINE YOUR KIDS PLAYING NEXT TO IT…. 3. IF R22 HAS ONLY 0.055 GWP AND MUCH LOWER ODP THEN R410A WHAT WAS THE POINT OF PHASING OUT R22? CAN ANYONE EXPLAIN IT ? WHAT AM I MISSING? IS IT POLITICS MONEY OR WHAT? THANK YOU FOR SHARING GREAT VIDEOS!

[@smacleod69]

It is all about money and power. There is nothing noble about these regulation changes. but If you wanna save on cooling. Move to a dry climate and build a "Wind catcher" system in your house and save 1,000's of dollars each year.

[@jerrylockhart3069]

Yeah, they were blocking me in the comments 😅

[@jerrylockhart3069]

We have 5 ton system for 25 pounds of refrigerant circuit

[@jk-mm5to]

Can I make an adapter and use it to refill my lighters?

[@threestans9096]

no cuz it wouldnt even ignite.

[@ladas1]

No coz when R32 does burn it produces hydrogen floride - and that is lethal

[@jerrylockhart3069]

So was 134 @ now they’re using to 1234 XYZ

[@daveydave9884]

I’m wondering what’s gonna happen when these guys start recharging 410 systems with 32 🥴

[@jerrylockhart3069]

Maybe if they made the goddamn coils till last night leak, the 410 like a sieve, we wouldn’t be in this conversation😢😅❤😮

[@hazendismukesjr.8319]

😂 What do you think about pressure clamps ??

[@jasonseifried7192]

Stud guards

[@Sctronic209]

Nail plate

[@Wade6242]

Government redistribution of wealth

[@brycelawmaster3746]

changing refrigerant has nothing to do with the environment and all about money

[@gerardos846]

😮

[@kennyjustman933]

can i pull all my 410a out and direcrtly replace with r32?

[@ronbutcher1130]

No

[@RETread-xh6fr]

Not to get political but if you don't like all these tyrannical mandates, vote very carefully in November.

[@danielwalker1922]

Lets go back to r22

[@TerryRGraham]

True Blue vacuum hoses will not reach 10 feet, nor would you want them to.

[@youarethecreator1]

Look up KZbin "Refrigerator of DEH-TH Why are they exx ploh ding ? :SOLVED"

[@jamesbooth3360]

FJB and his EPA! They are returning the Southern US back to hard living. Low lifespan equipment and high electric costs are making AC unaffordable.

[@grashoprsmith]

Bro, you lack critical thinking skills. I feel sorry for you

[@jamesbooth3360]

@@grashoprsmith Why don't you explain it to my simple mind?

[@grashoprsmith]

@jamesbooth3360 the same issues existed regardless of who the president was or is.

[@jamesbooth3360]

@grashoprsmith Now, who lacks an objective view of reality? I feel sorry for you.

[@grashoprsmith]

@jamesbooth3360 equipment didn't magically last longer 4 years ago under trumps epa. This stuff was in process under the orange narcissist's epa, too. Corporate greed is the reason stuff doesn't last as long. Couple that with smooth brains like yourself doing bad installs.

[@Kovaction]

I just want to say... If you have a furnace, then the natural gas or propane that burns is WAY more likely to burn then R32 or R454B. Did you know that R410A can also burn? It just happens to not cross the magic line to be A2L. The fear is from regulation. This stuff burns about as well as firewood that's been soaked with water.

[@threestans9096]

YES. thank you! saw a video and a guy explained how poorly it burns. The flames move slower than you can walk.

[@WhatIsYourCard]

Thanks for bringing up the lobbyist talking points for why this change isn’t significant. The “burns like soaked wood” is bullshit. If the concentration reaches its LFL it will ignite like propane. States across the nation do not have the licensing or insurance of quality of work that should be required to install flammable refrigerant in homes.

[@youarethecreator1]

Incorrect. Natural gas isn’t under high pressure where it can explode. Old natural gas furnaces have a draft, newish 20+ years will shut off the gas valve if safety’s fail. Old natural gas commercial boilers have the explosion potential If the regulator is stuck open to the pilot and gas builds up in the heat exchanger. Even then it’s no danger unless some tech like you doesn’t know what he’s doing and puts a bbq lighter in there to light the pilot.

[@Kovaction]

@@youarethecreator1 no sir. It takes the right mix of fuel air and an ignition source... whether the A2L gas is there or not, it just doesn't ignite easily. Sorry. It's extremely unlikely!

[@youarethecreator1]

@@Kovaction Then why do they have sensors to turn off the A2L units if there's a leak? You see now?

[@pearlrival3124]

its just propane guys not gasoline. yes weve had fun with it.

[@kennethbubser9601]

EPA nuclear weapons not acs

[@takleung7130]

I think most people that says flammable refrigerant is a bad idea are the DIYers. I can't imagine a properly train hvac tech would be scare of the new refrigerants. I would question the proficiency of any hvac tech that refuse to work on these.

[@user-ir2zv1xx5q]

Money laundry

[@RobertTuck-vo8cw]

There is a lot of unfounded hype about the "flammability" of A2Ls. Does everybody use non-sparking tools around natural gas/propane?? Does every tool used when installing a furnace meet the proposed rules for A2Ls?? Do all furnaces require leak detection and alarms? Do gas stoves and gas grills require them?? Gas water heaters? Dryers? Fireplace logs? How many people around the world have been hurt or killed by incidents involving A2Ls burning??? The answer to these questions is NO and NONE.

[@Kovaction]

I have similar thoughts

[@thomeedee]

Bit of a shill vibe .

[@joez.2794]

Shill for whom, exactly?

[@Hvacrpro123]

It’s not really flamible

[@darrinburkowske5162]

This is the most idiotic refrigerant they have come up with. Who going to be the first to die from this crap.

[@enemyofthesheeple]

Very bad idea

[@Starryeyed666]

Sacrificing your family's safety for the planet's "safety" 🥴🤡🌍

[@Kovaction]

See my comment as well. A2L refrigerants are nowhere as dangerous as natural gas and propane, which are used in many furnaces and gas fired heaters in RTUs.

[@enemyofthesheeple]

@Kovaction I've already heard of people getting badly injured from explosive freons. So in my opinion very bad idea I will never w9ro on explosive refrigerants. I refuse

[@Kovaction]

@@enemyofthesheeple mildly flammable is not explosive. I'm not a fan of this change but I'm not afraid to work with this refrigerant either. Common sense and care will carry us through.

[@HVACRTECH-83]

​@enemyofthesheeple well guess what bud? You don't have that option. You will be on board with it, or get the f out the trade.

[@HVACRDUDE]

ALL THIS TALK ABIUT PULLING DOWN. BRO, IF YOIR TAKING OUT A 30 YEAR OLD EVAPORATOR AND REPLACING IT. NO MATTER HOW FCKN GOOD YOU ARE, THERES STILL REFRIGERANT BOILING OFF, AND OLD OIL TRAPPED. SOOOOOO.....IT DOESMT MATTER IF I PULLED FOR 3 DAYS IT WOULD NEVER HOLD BELOW 500 DUDE., LIKE DO YOU HAVE ANY REAL WORLD, LIKE IN THE REAL REAL WORLD TECHNICAL TRAINING? BC IT DOESN'T SEEM LIKE IT

[@Sightthrough]

Sounds like you don't know how to pull proper deep vacuums. Big hose, no manifold set, pull the core on the suction line, micron gauge on the liquid line. On a purged system with no open compressor I easily pull 350-300 micron vacuums line 30-45mins on residential.

[@grashoprsmith]

Yeah, wtf you talking about. Especially if it's a split you aren't even pulling vacuum on the condenser. It's Hella easy to pull a good vacuum.

[@tedbell4416]

gwp, odp 🤡

[@julitolabor7086]

Or GDP, Gross Domestic Product…ahh business as usual.

[@jerrylockhart3069]

We have 5 ton system for 25 pounds of refrigerant circuit