Small home made reusable refrigerant tank

Well a good number of us use old green propane tanks as a container for scavenged refrigerant or to recover into, but to do so we have all ways have had to mod a torch head or messily braze in a schrader. Most of thees solutions have left much to be desired and all have perspective reliability issues.

After trying to figure out a better method it struck me, why not use a can tap for it? So I set out and checked the threads as luck would have it I found the exact tap needed, so off to try it out!

First thing you will need:

- 1/2" UNF tapered thread tap.
- a 27/64th Drill and a 29/64th Drill bit.
- Access to or have a drill press with a cross vice preferably.
- A thread sealing compound rated for gas use at the temperatures it will be exposed to.
- A can tap (You can get them from frosty freeze cheap)

Get an old EMPTY propane bottle and use a valve core remover tool to take the schrader out of it, then blow some low pressure air through it for several minutes to purge out any remaining gases. Cut off the thread leaving as much of the stem as possible.

Drill the hole out first with 27/64th drill taking it slow and steady, then ream out further with the 29/64th bit ensuring a slow smooth bor hole.

Dip the taper tap in oil and cut a 1/2UNF thread, take your time to ensure it is aligned right and straight, you want a good quality thread!

Once the thread is cut wash the inside of the cylinder with methyl alcohol (IT IS TOXIC & FLAMMABLE so don't touch it if you don't know how to use it safely) and then dump out and dry the inside of the cylinder.

After drying out and cleaning the cylinder take your can tap valve & remove the pin and O-ring off of it. Clean the threads with a good quality degreasing agent and test fit to the propane tank to ensure a smooth tight thread and fit.

Allow all parts to throughly dry and then apply thread sealing compound to the upper half of the threads and bold on tightly and then torque it a bit to ensure the thread is 100% engaged and the sealing compound has effectively coated all the thread gaps.

Allow sealing compound to cure for the night and half of the day (24Houres) then vacuum out the bottle to the usual 500 Microns or better for minutes or so, then break vacuum with N2 or refrigerant. Pressure test it for the day to ensure it is adequately sealed.

The burst valve in a propane bottle is set from 250 to 300PSI I have yet to actually see it go when recovering R-22 into one so it must be the upper 300 range.

SPECIAL NOTE: Do not forget to relabel the bottle and or repaint it to match the refrigerant inside and never put any refrigerant that will exceed 300PSI at 40C(105F) into it.

thats good! what is the point though? sorry im new to phase

The point is that it is a much more reliable method of storing home recovered refrigerant from small systems that we are modding as the valve is rated for refrigerant usage and is much more durable then a modded torch head. For thoughs who are limited to using air duster as refrigerant they can now make an easy re-usable cylinder to store it in when they mod their system as well.

How much time did this take you (excluding the time waiting for pressure etc), Xeon? I think you could amass a small fortune selling these things to noobs, if you were so inclined! ;)

Ah legalities though, can't sell this sort of stuff. It took less then 30minutes to do the purging, drilling, tapping, cleaning, it is the curing time of the sealing compound that takes the time 24H then rest is fairly quick.

Nice job! I love those little green tanks.

That's really too bad, but I can understand the legal constrictions. Really, the hardest part of the process is acquiring the tools, like the drill press and tapper. Assuming I can find them, I've give this a go over the summer, and save some money on a recovery tank!

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Originally Posted by Starkiller42

How much time did this take you (excluding the time waiting for pressure etc), Xeon? I think you could amass a small fortune selling these things to noobs, if you were so inclined! ;)

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Even though I'm sure they would hold up to their rated pressure beautifully, I wouldn’t sell a modified non-refillable LPG cylinder for any uses other then its sole intent. It looks like a great little tank, and I may make one in the future for my self, but I would haste on selling due to liability issues.
Lets say someone filled it with a higher pressure gas and the safety popped and hit that person in the face, the liability would come back on the person that changed the tanks functionality. and I really don’t want to sound like I’m wineing but in the EPA section 608 certification litiature, I read that one of the main reasons that non-refillable cylinders are illegal to refill is because:
say the tank was left open for a long period of time, or it got water in it somehow. The integrity of the cylinder walls would be compromised, thus the cylinder "could" fail under pressure before the safety had a chance to relive the pressure. That really only applies to the carelessness of people that would leave this thing sitting for a few years in a humid area, but they are out there...

Still I like the idea, who makes that valve?

Aye, I realized the folly of my ways shortly after posting. The irony is that the biggest market for these things would likely be the relatively inexperienced builder, whom only intends to make a couple units, and whom therefore is most likely to screw up with this thing.

Let's just call it a brain fart and leave it at that ;) .

Technical Chemical Co. "Professional Dispensing Valve"

I get them from frosty freeze and their dirt cheap, the mode to the valve is super easy the Oring can be pulled out if you have finger nails and the pin a good pair of pliers and a strong grip it slides out.

http://cgi.ebay.ca/R-12-Pro-Dispensi...QQcmdZViewItem < This is a great starter kit

http://cgi.ebay.ca/R-12-Professional...QQcmdZViewItem < For thoughs who all ready have tons of hoses.

For the newbs that attempt this project is why I was so specific as to the limits of it and what would be a safe pressur / temp range.

A modern recovery machine will pump up to 525 to 550 psi high limit, recovery tanks are 350psi normal or 400 psi for R410a and they are much thicker than propane tanks.

exactly this is NO substitute for a proper recovery system, this is simply a stop gap to allow recovery of low pressure refrigerants such as R-290, R-22, R-134a, and such.

I do like where you are going Xeon. I think you should have installed a T though with a pressure relief. Possibly a pressure cutoff that plugs into your home made recovery. I like that your looking to help the environmental problems that XS does produce in small quantitys.

Not DOT approved and way aginst the law as far as EPA regulations! (sect - 608)

big $$$$ fines involved, so id say watch out for the men in suits,


very nice $ saver if every thing works out :)

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Originally Posted by V2-V3

Not DOT approved and way aginst the law as far as EPA regulations! (sect - 608)

big $$$$ fines involved, so id say watch out for the men in suits,


very nice $ saver if every thing works out :)

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You do realize the irony in this statement? Albeit true it is all so true be making these units AT ALL is a violation of the law in of its self. So in the end any thing goes. BTY DOT is just for transportation, just don't take them any where ;)

DOT says you cant transport them, EPA (THE FEDERAL GOVERNMENT) says you cant use them. it is a huge violation that they will fine/jail you for. the EPA has really stepped it up on section 608 violations (refrigerants)


making these units is not a violation of any law unless you posses refrigerants and do not have an EPA 608 license to handle refrigerants. not sure about how many people on the forums do or do not have their certs. I doubt any one would actually be pwnt by the EPA unless they posted pics of them dumping 4000LBS of R12 into the air :D
A good rule of thumb: if they wont let you buy it with out a license its illegal for you to handle it.
(if you want to stay legal) you do not need a license for some very useful refrigerants here are a few off the top of my head. most of them can be purchased from places that have alternative uses.

R290
R600a
R600
R744
R50
R702
R704
R717
R718
R720
R728
R732
R1270
R170

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Originally Posted by V2-V3

making these units is not a violation of any law. :D

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Yes it is every unit must be certified by epa and dated, older units before 1993 iirc get a gradfather clause and only need to evacuate to 10hg vacuum.

New units need to be pulled down to a 300 Micron Vacuum
and must have UL equipment or its your neck when anything bad happens

I could be wrong, so im going to look at the 608 codes again. :P

Unless you have your system commissioned it IS illegal.

V2-V3: throw up R410A on that list :D .

now to use this all i need is the tank and my manafold right because it is low psi's

Why not just use a empty refrigerent tank? I have about 10 of them I was going to use them for an onboard air setup for my truck. I think I can spare 1 or 2 for recovering.

sure but one thing where do you live because i live in canada

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Originally Posted by Starkiller42

That's really too bad, but I can understand the legal constrictions. Really, the hardest part of the process is acquiring the tools, like the drill press and tapper. Assuming I can find them, I've give this a go over the summer, and save some money on a recovery tank!

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you can drill ith hand drill and tap with tap and tap holder wrench, but remember you must only fill to 80% and do not put high pressure gas in them. recovery machines can pump to 525 or 550 psi and that may bepast rupture point. best to spend 60 to80 dollars and buy a recovery tank that is dot approved and 410a models can have 400psi in them.

nevery fill any tank over 80% by volume, not all gases weight the same as water,which you scale is calibrated by. water has a denisty of 1 and air has a density of 1 in imperial system of measurement.

http://www.r22.org/prod_list.php?mai...Recovery-Tanks
$80 delivered ;)

r22 is classified as a very high pressure refrigerant.iirc

Very nice find, NOL! I may just snag one of those instead of spending money on tools, or bidding on shady-looking ones from ebay ;).

I buy my refrigerants there, fairly decent deals all including shipping price.

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Originally Posted by V2-V3

Not DOT approved and way aginst the law as far as EPA regulations! (sect - 608)

big $$$$ fines involved, so id say watch out for the men in suits,


very nice $ saver if every thing works out :)

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EPA is a US governing body ><

Sweet deal on the Proper recovery cylinders! Though for some reason I doubt shipping is free to Canada lol.

The cheaper recovery tank here, similar to the one you linked, costs U$S330:mad:

hey xeon do i need a recovory system to use this recovory tank

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Quote:
Originally Posted by V2-V3 View Post

making these units is not a violation of any law.

wdrzal responded... Yes it is every unit must be certified by epa and dated...

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Hmm... I would think that if a person has EPA certification for working with refrigerants, does proper recovery/disposal of said refrigerants, and is building a system for his or hers own use only (not to sell), then it would not require EPA, UL, CE or anyone elses stamp of approval on your design.

wdrzal since you made the strong statement that I quoted above, can you provide better clarification and/or a link to an official document or source to back it up?

If there is a requirement as you stated, would there be exceptions below a certain size (e.g.; less then a given horsepower or CFM).

It would be most appreciated by myself, and I'm sure others as well.

Thank you :D

can any one tell me if this tank is all i need to recover r134a or do i need a recovery unit and the tank

you will need something to "pump" the charge into the containment cylinder and pull a low vacuum on the unit. a simple rotary compressor should work.

exahertz do you know where i can get one now i have a vac pump but that won't work right

It been a long time since I took a EPA test,was in the 1000 nationwide but I'm 100&#37; positive that
"only approved recovery equipment is permitted" in fact there is a grand father clause if your equipment is older than dec 1995(don't quote me on that date) you can get a way with pulling only 10hg vacuum.
all my equipment is newer than 2002 shop & personal
on the back of every unit is month and year produced. you wear able to get certified before necessary & recovery equipment was available but it was a pain since it was all hermetic, you should know that if working for polycold as each technician must have his own license.

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Originally Posted by ruffus

exahertz do you know where i can get one now i have a vac pump but that won't work right

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no. Oil Cross-Contamination will occur and you absolutly can not connect a vacuum pump's linet to a pressurized system (Damage WILL occur).
I was talking about a rottary compressor for refridegeration units, or a hermetic compressor. almost any compressor will work but the question is how long you have to spend waiting for it to move the charge. in this case you will need a LBP/MBP compressor (and larger is better ;) )

exahertz so can i just use the compressor that is in the system sorry if i am asking some dumb qusetions i just want to get it right

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Originally Posted by ruffus

exahertz so can i just use the compressor that is in the system sorry if i am asking some dumb qusetions i just want to get it right

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http://i44.photobucket.com/albums/f9/laserskys/LPG.jpg

hey exahertz can i use this http://cgi.ebay.ca/Hot-Shot-Spooter-...QQcmdZViewItem

It looks like it would work fine. just might be a little more physical effort then most technicians are willing to do. check to see if it can pump liquid, otherwise, if its only vapor then these singel valve recovery cylinders would be a bad idea as it would take you forever to move all of the refrigerant as vapor. again if it can only pump vapor you would need a dual valve recovery cylinder so as to use the "push pull method" for refridgerant recovery.

I think this is how its set up, i made this drawing (anybody, PLEASE correct me if im wrong!!!)
Liquid recovery method:
http://i44.photobucket.com/albums/f9...overliquid.jpg
http://www.shutup-n-ride.com/Forum_P.../Push-Pull.gif
http://www.galaxair.com/galaxair/PDT...URPRESSION.jpg

There are several methods, you will mostly being recovering vapor . there also a push pull method for large amounts of liquid. that wrong ,but itdoes depend on pump some pumps have as many as 4 ports most modern have 2 a inlet from system and outlet to tank.


mytekcontrols, just because you either took a open book on line EPA type1,as many here did, or have a UNIVERSAL EPA cert, that a long long way from being a engineer to design recovery equipment.;)

that just supposed to mean you have the technical knowledge to operate the equipment as required.

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wdrzal stated... wdrzal stated... mytekcontrols, just because you either took a open book on line EPA type1,as many here did, or have a UNIVERSAL EPA cert, that a long long way from being a engineer to design recovery equipment.

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Actually I took a real test, not open book, and not online, but one that the company (Polycold) paid for all it's technicians to take (including cryo-tek with whom I worked with). And yes I was certified to UNIVERSAL by the ESCO Institute.

At first I was a little perplexed at the comment about designing recovery equipment, because that was not really what I had meant by my original question (stupid me). In my attempt to catch up on what has been going on around here lately (I was off-line for a couple months), I have been skimming the various posts, and I guess I skimmed this one too fast and misunderstood your earlier statement about the legalities of making what I though were refrigeration units, not recovery units. Sorry :shrug: :shocked:

I totally agree and see your point on recovery machines and related equipment (recovery cylinders). And I although I do admire Xeon th MG Pony's very creative approach on re-using a propane cylinder as he has shown us. I can clearly see why it would not be legal (or safe) to sell these to others.

At the place I do contract work for, we frown on the re-use of disposable cylinders, and not just because of the possibility of water getting into them (which wouldn't be true for our situation), but also because of the thin wall nature of these tanks. Imagine for every time you filled and then empty the cylinder, you are expanding and contracting it's thin wall. Over time this will cause metal fatigue that could very well cause a rupture. Remember the original design only assumes one filling, and one emptying of a disposable cylinder.

But none-the-less, still a very creative approach.

thats why I make it clear it is a stop gap to buy time to get proper equipment, not as a final solution. it should last safely for some one to do two or more builds (Probably much longer if they take good care of it) and either by then they'll be don building or hope fully invest in proper equipment.

You could also make a basic rupture protection sleeve for this, be it wire of some sort, or a PVC sleeve rated for a much higher pressure. If its snug, it will help protect.

wrap it in carbon fiber, that should hold it.

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wrap it in carbon fiber, that should hold it

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Wow! World's most expensive DIY recovery tank :D
But it certainly would make it stronger.

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thats why I make it clear it is a stop gap to buy time to get proper equipment, not as a final solution. it should last safely for some one to do two or more builds (Probably much longer if they take good care of it) and either by then they'll be don building or hope fully invest in proper equipment.

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I totally agree, and you haven't tried to sell the idea any other way :)

Now I also know that some guys are using these tanks for phase separators in autocascades (another rather novel idea). But due to the nature of this application, I really don't think it is a very safe way to go. Even though the cylinders are painted on the outside, I wouldn't trust this to completely stop rust caused by the inevitably moisture that gets past the armaflex insulation (a rather popular way of insulating). In fact the moisture problem is many times worse then a tank being used in a free air recovery situation. Once moisture gets past the insulation, it stays there for an indefinite period, continuing to work its way through the paint where ever it can. Add to this the fact that the "propane cylinder-phase separator" under goes a major change in pressure each and every time the system is either started or shut down, and you have a recipe for disaster.

Yep, I agree with that and have taken the precuation of buying a box of temprite 304a's to use instead. Though your bullet strainer to phase sep idea is very very well. I think modifing a small receiver would work as well.

that 1/2 UNF tap is it just 1/2 UNF or does it have a number after UNF

straight taps need to seal on a gasket or O ring since that can not be done, just goop-ing on some type of sealant or silicone is not the correct way to make that seal.

I would use a valve that had a tapered pipe thread 1/4 to 3/8(depending on tank)on the inlet and drill appropriate hole size and tap with the matching size tapered pipe tap. Tapered pipe taps seal within the threads ,straight taps do not, (thats why the valve had a O-ring on it). you can put a wrap or two of Teflon tape or some pipe dope on the threads,either one just helps seal the thread to seal. just tighten and the seal is complete, no waiting for something to dry.

After you drill when using a npt tap you will need to use a reamer to taper the hole before you tap. That is the proper way to make a npt hole.

Why would you ream something if its going to be taperd after its tapped? unless your talking about some kind of taperd ream.

either way, after you tap be sure to hit the top and bottom edges of the threaded hole with a chamfer to deburr it and give it a nice clean bevel look. though i guess it would be impossible to chanfer inside the bottle.

also you'll get tap oil inside of the bottle, along with metal shavings. so you will need to flush the bottle with alcholo and then pull a vacuum on it to evaporate the remaining fumes.

Exahertz everything you said is wrong,you need to do some reading on taps & dies and how to make threads, you drill a straight hole and the pipe tap has the taper built into it, the same goes for a pipe die.

when drilling a hole that does not penetrate all the way thru the metal and is straight fine or course thread you need a 3 piece tap set(most come this way) starter tap, regular tap,and bottoming tap.



there are all kinds of threads,and ways to make seals , there's a whole book just on that and even that won't teach you what a good mechanic/machinist will.

how am i wrong? why would you ream (widen the opening of) your pilot hole before you tap it. what difference would it make with a taperd tap? you would just have to ingage the tap a little deeper. thus your NPT-male would have to screw in deeper to seat.

i've tapped with NPT BSP and Straights. and you tell me that nothing i said makes sense? so oil and metal shaving wolnt get into bottle, geeze! I want some of those taps! and let me guess, you dont clean up the top edge of the newly tapped hole? yea lets see how long that initial "starting lead" thread lasts when its only 1/1000 of an inch paper thick and sticking out at the top. i always chamfer my tapped holes, its a clean and durrable finishing touch, plus it helps guide the screw to ingage.

ok let me clarify

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That is the proper way

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Yes you should ream the hole first as the tap is supposed to cut threads only not take out material. If you use a npt tap without reaming you wont get the amount of threads that you would if you used a tapered ream. Understand? Do you want me to draw a picture?

turn the bottle upside down when taping, you can get away without using oil on soft metals like copper,brass aluminium,even mild steel as long as the tap size is small enough . Plus take its slow and keep reversing the tap to cut off the shavings. when to reverse depends on number of flutes on tap.

oil is always prefered,but tapping can be done without it. some metals used in aircraft that are cnc milled with no oil or solvent as in would dammage the metal.

a tapered ream. thats what i was wondering about. i guess it would make tapping an npt a lot easier/controllable depth, though i tap 1/4" npt in stainless using only a 7/16" drilled holes and they work quite nicely, they get a little harder after the first inch or so but the tap seems to manage.

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Originally Posted by wdrzal

turn the bottle upside down when taping, you can get away without using oil on soft metals like copper,brass aluminium,even mild steel as long as the tap size is small enough . Plus take its slow and keep reversing the tap to cut off the shavings. when to reverse depends on number of flutes on tap.

oil is always prefered,but tapping can be done without it. some metals used in aircraft that are cnc milled with no oil or solvent as in would dammage the metal.

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You can also fill the flutes with a bearing grease to catch the shavings.

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Originally Posted by 2long4u

You can also fill the flutes with a bearing grease to catch the shavings.

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:shrug: idk bout that one, maybe with harder metals as the shavings would be smaller and less likely to get between the teeth, but then again you might want bigger shavings for that like in softer metals :shrug:
good idea though and worthy of testing, i might just keep that in mind

Thats how we tap oil pans for a bigger drain plug when the customer strips it.

OK well i got my valve today from frosty freeze and i got out my tap and die set and i found that the die that fits on to the valve is a 1/2 20 NF so that means that the right tap for this valve is a 1/2 20 NF i can not find any taps that r UNF is there even such thing

I beleive that NF/UNF and NC/UNC are the same

ok thanks i think that UNF and UNC is in th USA and NF and NC r canada

The exact tap is 1/2*20 UNF Taper I use the one from: P&N Austria GH5 HSS.

Xeon where did u get that tap from

an industrial suply shop that was near my place.

someone said to put in a relief valve, but they have a built in relief valve, it is the hole next to the threaded torch connector thing, it is set to 300-400psi

xeon well i don't know what i did wrong but i got my tank all together and dry and i when't to pressure test it and when ever i put nitrogen then shut all the valves and took off the hose then hooked up my high side of my manifold to see if the tank had anything inside but there was nothing no psi's in small tank so i did again to test for leaks but there was none but again when i took off the hose and test to see how much psi's it had it had none what am i ding wrong please help

I have no idea, did you use a good quality Thread sealant that was rated for this type of service? I used: Permatex Thread sealant, it matched most of the requirements that it would need to withstand for this application, so far it is holding R-22 and R-134a with zero leaks or seepage ( I check the wait of the bottles every two days to watch for seepage, and so far been nearly a month and not even the slightest change in the weight!

know it is not leaking around the threads loses all psi's after i close the valve and take off the hose like the valve does not close how can i find out whether the valve works or not

How do you know it is not leaking around the threads?

put it under water and admit 100psi to it, and see where the bubles come from.

well when i put in 200 psi and soaped it all up and there was no bubbles but this was with my hose,regulator and tank still hooked up then i shut the valve on the small recovery tank and shut off my N2 and when i on hook my hose i lost all psi's in the tank i can open the valve back up and no n2 comes out could it be the valve (I did take out the pin and o-ring)

well did you tighten up the stem packing nut? or did you dismantle it to ensure the valve is clean?

yes i did but i will go back and try it again just to make sure

ok well ifound a piece of rubber where it should not have been so i tookit out and i got it to hold a vac so if it does not lose the vac buy tomorow after work i will pressure test it then thanks for your help

DIY separator before use and a few after,no safety device like a relief valve, notice the thicker flat plats bulging and the distortion of the tube on the sides. you decide how many psi it could have taken or seconds to catastrophic failure.

Plus another shot I found of cascade quality braze work. in cascades,interstage HX I didn't name names as my intent is not to embarrass anyone or pick a fight ,but a picture is Worth a thousand words in these cases,of what is not acceptable.

This work scares the Hell out of me :shakes: :shakes: :shakes:

Last pic: Pressure tested with 25bar -no leaks. If I would cleaned the brazings, you wouldn't mention here...

well i think that system is scary and i would not would to be around when it does fail i don't under stand why the person would not go with the right size copper tubing

scary, especially the reciever.

I admit, it scared me a bit too when I first saw it, but really most of the "bad look" comes from the uncleaned braze joints. If those were cleaned up I'm sure it'd look a lot better.

And if it was sufficiently pressure tested, then my other primary concern would also be abated. I've seen a lot of crimped tubing in professional jobs; sometimes you just can't get the right sized tubing/connectors that fit your needs, so you make due with what you can get. And test the hell out of it afterwards.

what does that have any thing to do with this thread walt? The bottles have an integral safety release valve in them.

starkiller42:
look at the bottle, it have make som progress in making bended ends :)

About safety,bottles have integral safety devices, what if people don't understand what drill size for what tap or the correct tap to make a seal and the threads are not cut deep enough to hold the pressure without stripping & blowing the valve off. The pressure of propane in the bottle is in it's saturated state, so go by P/T chart for themperature,ambiant temperature is what the bottles are designed for. a recovery machine could pump up to 525 psi.

Its about modifying or taking DIY one step too far past your knowdledge of ALL the FACTORS involved in building a safe device.

Ah yes good point walt thank you for answering my question in how it is relivant, I tend to expect any one messing with this to have don their home work, and sadely I tend to find it quite the opposit!

OK i have a A/c that i need to take the r22 out of (don't know if it has any in it) now this unit says that there is 14.29 ounce's in it can i put all of this r22 in to this tank

I'd say invest in a true tank, and get something way over the top, like a 20lber minimum. Overkill solves most problems. I agree with walt on the first pic, thats a horrible problem. Definitly cannot use huge diameter tubing in this application without banding it or the like or structurally reinforcing. The second pic should have been done neater and mroe planning would have been nice, but its most likely fine and just dirty. Reducers are always better to use, and easy to make, so I'd recommend them to all. (A set of swags solves most problems with reducers)

the tank will hold a pound of R-22 with plenty of head room to spare, If I recall corectly I calculated it to just about 1-1/4 pounds max or R-22.

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Originally Posted by ruffus

OK i have a A/c that i need to take the r22 out of (don't know if it has any in it) now this unit says that there is 14.29 ounce's in it can i put all of this r22 in to this tank

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you tell me,???

Also dose everyone know the working pressure and bursting pressure of the different sizes of tube you work with??????

What about DIY expansion & recovery Tanks ????? larger tank=more surface area(more square inches)= more pounds per square inch. bigger tanks=bigger bombs.

You Guys are going to give me a ulcer @ least use a pressure relief valve on any thing other than a single stage with a pure gas that pressure can be predicted. Also Buy tanks you know the pressure they can handle.

Some of the gases you guys are using are not commonly used as refrigerants and are extremely high pressure @ ambient temperatures.

I've said this before,many guys are over reaching your learning curve. I suggested you take a 8 to 40 hour class to get certified for recovery + be able to buy pure refrigerants and you would have been taught the basics, but our government screwed that up by providing a on-line open book test where you only have answer 50 question and get 80&#37; correct with a open book.:shakes: defeated my intention for you guys to learn about refrigerants,specific gravity and pressure conversions.

But this is a International Forum, Take a good look how that copper tube distorted and the flats plates bulged. I actually applaud the person who posted that pic as most hide their worst mistakes & we know many have happened. I hope every time you consider making something that deals with pressure vessels, picture that DIY bulging distorted Copper Tube then

Please reconsider,I don't want anyone here hurt.:up: :up: :up:

This is not a game!!!! and there are no "do overs" or "second chances", even if its a serious injury,who wants there eyes blown or burnt out?

you are no longer wiring up 12volt DC fans, give pressure and these gases the respect they deserve. :) :) :)

Lol I personally find it pretty funny that this entire problem (I mean, as far as recovery cylinders go :p, safety and knowledge still need to be learned!) wouldn't exist of manufacturers produced a 5-or-10 lb cylinder. I think they could get a pretty decent sized group of enthusiasts to buy them, and even professionals who are tired of lugging huge tanks around. Sell them for $40 a pop and we're golden.

Sad thing is, we're probably still too small of a market. The only way a product like this would get released is if some enterprising individual decided to order a large number of them custom made. If that person was really smart, he'd also re-packed refrigerant in these smaller bottles, so an enthusiast can get more high-quality refrigerant than he'd ever need without spending $400.

**end rant

Ya 99% of the jobs I do I never need any thing over 5 pounds, the charging cylinder I use most is only 16oz I've got two, 1: R-22; 1: R134a with thoughs two I never need more with most the equipment I see, as for repairs most are usualy less then 2 pounds refrigerant. Realy wish they'd just make a mini-recovery cylinder!

Even with the charge cylinders I use the scale with them, nice to see how much is left :)

Hmmm, I wonder if we can convince one of the store owners around here to order 50 2lb. refrigerant tanks? If you can get the tank for $30, and better yet fill it with some really nice gas (cough r507 cough) ($400/25lbs*2Lbs= $32) and sell both for $80, I see a pretty decent profit margin!

Smaller tanks don't teach you how to safely handle high pressure gases,while they do fit this unique hobby/profession better for most.

Lets knock off the LOL when discussion serious matters.OK

smaller tanks still does not get around the laws about selling and recovering refrigerants. getting smaller tanks made is easy.the certifications could be more than the tanks unless it was a very large run. I really can't get a handle on oc'ing I original thought as faster cpu's became available the need to oc would decline as ocing started when you had a 20 hz chip and a green monochrome 12" monitor,No gui,only dos,long before windows.you guys today complain about slow.............

But is seems the spirit in all of us to be the fastest ,have the best and push boundaries ,thats in the human soul will never end. what ever we have,there is some who whats to one up it.so as I been watching XS grow so will the information age we now live in. thus the need for faster,better,cheaper parts that are dependable,who wouldn't like to have hardware that never fails,or software that never crashes???

yes hobbies have a cost,buy I see thousands spent on CPU's and mobo and memory.

Believe me if there was a simple answer I be the first to let you all know.

The only answer is to buy equipment and use it its its intended way, I'm the first guy who likes to build everything himself,but sometimes to comply with all the safety regulations ,It's cheaper to buy mass produced tanks and equipment.

One of the point many of you guys are missing is that many of YOU GUYS are going to be the next generation of engineers and designers. You must know start with the basics. Kinda ironic the richest man in the world quite college.
But a doubt MS & many large company's accept many applications from google engineers. But with that said you don't need a engineering degree to get a good job,just know your job and be the best at what you do. A lot of people from XS have proved that.

I wish I had the advantage to learn about fields I never knew existed when I was 12/14/16 before the Internet. You guys here at XS and on the net have the greatest advantage of all.

Knowledge,almost unlimited knowledge,so use it wisely. It's not about a old fashioned pissing contest,be above that!!!!!:up: don't wast your time or your life,it much to short.Set a project goal (realistic) and research and complete it,then move on to another,then another.Never stop moving or you will be left in someone else's Dust.

refrigerators and window AC units don't blow up,but add DIY parts,building muli-stage cascade way before your time ,add ethylene,argon ,r23 etc,etc and then the effect of your actions becomes apparent.

Rant off .................................................. .....for tonight;) :) :)

Quote:

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Originally Posted by wdrzal

Smaller tanks don't teach you how to safely handle high pressure gases

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I know, I already mentioned that people must fully understand what they are doing. This just makes it easier and cheaper to do it right.

Quote:

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Originally Posted by wdrzal

Lets knock off the LOL when discussion serious matters.OK

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Personally, I think the most serious of subjects are the ones most in need of laughter. Humor keeps us interested, focused, and upbeat. So if you'll excuse me, *ahem*, LOL! There, now doesn't everyone feel better?

Quote:

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Originally Posted by wdrzal

smaller tanks still does not get around the laws about selling and recovering refrigerants.

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Of course not, but like I said before, they make it much cheaper an easier to do. With that in mind, I think we can both agree that a small commercial tank would promote the proper storage and recovery of refrigerants by amateurs. And distributing smaller quantities of refrigerants makes owning an otherwise very expensive refrigerant affordable. Sure taking a class/test may cost a lot more than this, but saving money is still saving money. I view it as no different than a super-expensive driver's ed class; just because I spent so much already doesn't mean that I want spend a whole lot more on a new $20,000 vehicle, no, I'm looking at a $3000 used vehicle.

Just my automatic rant-response kicking in here, ;).

I was wondering, to what extremes would one have to go to clean a used recovery cylinder as to use another type of refrigerant if the oils are incompatible.

is there a flushing procedure?
would this work: fill the tank half way with a flushing liquid, swish it around, pressurize the tank on the vapor side valve and remove the liquid/oil mix through the liquid side valve, repeat with clean (distilled) water, then pull a vacuum?

Use methonal alcohol, cleans and dehydrates. Then warm cyl and blow out with N2 or air out side then vac.

Company here flushes their coaxial exchangers with it to clean them out befor installing, seems to work great.