Refill a 1 lb Propane Tank for 50 cents! (The Safe and Easy Way!)
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- เผยแพร่เมื่อ 5 ธ.ค. 2021
- In this video I'll show you how to fill two different kinds of 1 lb propane bottles!
Here's an Amazon affiliate link to the brass caps for the 1 lb bottles:
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Here's a link to the flame king adapter (20 lb to 1 lb):
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Here's a link to the braided hose adapter (20 lb to 1 lb):
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Here's a link to the Flame King 20 lb propane bottle stand:
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Here's a link to the balance / scale that I use in this video:
amzn.to/3Iup9gA
Here's a link to the Mr. Heater fuel filter:
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"As an Amazon Associate I earn from qualifying purchases"
I have watched several videos on this subject, your video is the most informational. The only CHANGE I intend to make is to use a plastic dowel to release the excess pressure. Schrader valves are fairly delicate. I don’t mess with them unless it’s absolutely necessary. Love the idea of using the brass caps and soapy water to test the final product. I also wipe a thin layer of oil around the threads of the bottle before storing as they have a tendency to rust.
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Ive watched lots of do it yourselfers fill these bottles in their back yard and this guy is the safest yet. I like the brass bottle caps, Ill be getting some…….well done
Agreed - informative and safe. Good best practices.
Yes sir the brass caps are the way to go that's what we use we've been refilling them this hunting season.
I’m a bit late to learn about refilling. I’ve spent tons on disposables, never even tried to use my big tank to top off again. This video highlighted, safety, easily obtained gear (Hose-valve-filter-scale)and the Flame king bottles which I didn’t know of.
Thank you for speaking clearly, explaining properly and not rushing through each movement. 👍🏼
As someone who used to work in the propane industry I can very much appreciate your attention to safety especially the part about feeling the propane bottles in a well-ventilated area thanks
I put my bottles in the freezer for about 15 minutes and if the propane bottle is room temp, you don’t have to purge it. It pulls in about a pound every time. Works pretty slick.
Yep, I'm surprised this guy didn't know that or at least mention it. Been refilling these tanks for 30 years and no problems. Using those brass caps is a real good idea especially when transporting the tanks.
Steven, could you go into a little more detail on that. I think I follow but just in case a little mor explanation would be great. Thank you sir.
@@fritzkabeano1969 When the propane runs out, the bottle fills up with air.
you need to "burp" the bottles to remove the air.
My scale is metric so 450 grams is @ 1 lb.
If you get the Mr heater cable, be careful to support the bottle or they will develop a leak.
Mr. Heater recommends using a filter.
Many have stated their heater was ruined by not using a filter.
@jose the bottles don’t fill with air there is always pressure in the bottle. What you are “burping” os propane.
Very informative video. Thanks for sharing.
For disposables, use a Tee with two valves, then you can purge without unscrewing or messing with the vent.
Can you explain how to do this? I cant find anything online
Take a tee fitting and orient the bottle on the bottom. Place a valve on both ends. When you need to purge the bottle, close the valve to the 20 pound tank and oper the other valve that will allow the bottle to vent. Rinse and repeat.@@connorerhardt1767
This was a very good video on this procedure I am really glad to hear your explanation of the need for an inline fuel filter. I have watched other TH-cam videos saying that without the filter
you will eventually clog the Heaters with rubber fragments and or rust water and oil. I now feel confident that I can safely proceed.
Thanks to you Mr. Harwick Homesteader..
Far and away the best video I’ve seen on this topic. Thanks for sharing this!
Very well presented. Thank you.
I won't wear anything but cotton or wool just because of the danger of synthetic fabrics melting to the skin. Clothes that melt in the presence of flame should be illegal to manufacture. My aunt was playing as a little girl and fell backward on the edge of the fireplace. Her dress ignited and melted to her skin with horrible repercussions. She survived but that's enough to sell me on natural or non-melting clothing.
Had a crazy incident at work last year. I was wearing flame retardant coveralls and using a cutting wheel on a grinder. I had a tiny tear on the leg of the coveralls and the sparks from the cutting wheel caught the polyester on fire. When I looked down, the flame was 5" across and spreading, all the while melting my coveralls to my flame retardant shirt. I got it put out but it's crazy how fast it was spreading and scared the S out of me to be honest.
Those are good looking propane and propane accessories.
Yep, Hank Hill would approve😄
Great advise regarding the glows and protective glasses. Thank you!
At 0° the vapor pressure is very low. So freezing the empty bottle is really a good idea.
Also, if the main valve leaks, I just keep a propane torch head screwed on (unless it's a gusher).
I've never had the vent valve leak.
Hi From London England Thanks for the info this has been extremely helpful.
Thank you!! I've watched almost every video on the subject and ous is the most detailed, practical, and complete that I've seen :)
Except you forgot to keep the filter on for the second filling on the disposable tank :(. I won't hold that against you! Great job!!
Thanks for your very detailed info-clip!~
Thanks for sharing your video. I enjoyed watching. Take care and God Bless.
Great video. The filter is a great touch. It should take care of any oils or debris stripped from the hose as a result of high pressure.
In summer, I put the small tank in the refrigerator as opposed to the freezer since the big tank is hot. I generally look for a 30-50° difference (Fahrenheit). More than 50 or so. Your risk over filling. Less than 30 you end up with only about 2/3 - 3/4 capacity.
Found you again, popped in to leave an update. I'm doing almost this same setup with the hose with a valve and the scale.
But I'm not bothering to vent. I get about a half a pound per jug, and that's enough to make me happy.
I'm doing the Coleman bottles, and that valve is CHEAP. I have never vented, and had one fail already.
I have many bottles to refill. Thank you
Excellent excellent video.....Well done for sure. One thing I would mention is those pre-filters....the manufacturer says to replace the pre-filter yearly.
Well-Done & the propane filter is $12 at a Tractor Supply store
I thought I paid $10 for it at Cabela's..
3:45 the tare weight (0.6kg/1.4lbs) is actually stamped on the foot ring, like all refillable tanks. I just picked up a flame king kit for $40 on clearance from Menards.
Great info.
Some highlights from this great video and from comments:
1. The liquid is at the bottom of the tank and vapor at the top, that's why it's upside down.
2. Wear cotton clothes, leather shoes, etc, that are not static-prone, else you risk a static spark.
3. Always refill outside in a well-ventilated area away from your home and any source of spark/flame.
4. Mark empty weight on bottles so you know when you reach 1lb. of propane using a scale.
5. Use a screw-on filter to prevent oil from the hose from entering the propane (and potentially clogging your burner).
6. Use soapy spray at end to check for leaks.
7. Purge disposable canisters occasionally to allow you to continue filling it.
8. Open the hex valve vent on refillable ones to allow for continuous filling.
9. A flexible tube will allow you to measure the weight, unlike a solid/fixed metal adapter.
10. Pulling on the disposable relief valves can cause them to leak.
11. Putting bottles in freezer for 15 minutes prior may keep you from needing to vent bottles (from comments).
12. For disposables, use a Tee with 2 valves to purge without unscrewing or messing with the vent (from comments).
13. Coleman bottles tend to leak after a few refills so not recommended (from comments).
14. Manufacturer suggests to replace the propane filter annually (from comments).
15. Propane filter is $12 at a Tractor Supply store (from comments).
The filter is worth every penny.
I have it on good authority from Buddy Heater users that the best way to have your Buddy flame out in the middle of a cold snap is to not use one.
And I have been so impressed on the hazards of overfilling that I am going to buy a scale before I even try it.
@@TimeSurfer206 Yes, I use a filter on mine for this reason.
Well done. Good demonstration. Thank you Sir.
I like the respect for limits
Good teacher.
That rooster😮
very smart money saving
If you freeze the small tank before filling , you won't need to vent. I've been doing this for over 10 yrs and have had one small tank vent go bad from venting while filing. So freezing solved the problem. I am using a harbor freight file adapter. This work with non-refillable tanks.
Best tutorial on the internet! God Bless and stay safe. EDIT: How many times can you refill a bottle? Like a brass shell casing.
Unlike a shell casing....you are not subjecting the case to 13k to 65k lbs of explosion when refilling a propane bottle.
The highest ever pressure is still less than 400lbs...
and that's @ 158F!!!
so refill forever....@60F that's only 92psi
LPG (propane) gas cylinder-bottle pressure chart
Temp Temp Pressure Pressure Pressure
ºC ºF kPa PSIG Bar
70 158 2482 360 24.8
60 140 2013 292 20.1
54 130 1794 257 17.9
43 110 1358 197 13.6
38 100 1186 172 11.9
32 90 1027 149 10.3
27 80 883 128 8.8
16 60 637 92 6.4
-1 30 356 51 3.6
-18 0 152 24 1.5
-29 -20 74 11 0.7
-43 -45 0 0 0
@@JohnSmith-yv6eq Thank you, great info. Blessings
Nice work on the vid. How come u didn't use the filter for the normal 1 lb cans when refilling?
That was exactly my question and reason for looking to the comments to see if someone else had asked
Really accurate scale...with the weight of a filter,brass fitting and tubing draping all over the assembly. Geesh.
if the side valve leaks on a disposable it may be possible to cycle it a couple times to get it to seal, i could be wrong but it might be worth a shot.
What is the temperature outside where you are filling the tanks ?
More information for us hardheads! Thanks for sharing.
Jus started doing this myself then my pilot won't stay lit. Lol sent a new unit now I'm back in business. Cheers
U had air in green tank.
When I first did a refill, I couldn't hear any propane filling the 1 pounder after 30-40 seconds so I got a stethoscope to listen at the bottom and low and behold, propane was still filling the bottle. So for the first 5 refills from a full tank I just let it fill for about 9 minutes and the bottle is full with no purging or other fooling around with it.
Nice! I'll have to try that!
@@TheHardwickHomestead I use a scale, weigh empty, then after filling to check how full the bottle is. It took some experimentation to get the refill time down depending how empty or full the 20 lb tank was. But waiting, the bottle was being filled.
@@TheHardwickHomestead just have one question why you didn't use the propane filter on the second bottle to have a clear gas ?? Like you did on the first one
@@stevec3872 The valve on the flame king is an 80% valve which is why you don't need a scale to fill the flame king tank.
Yes, ditto on the freezer technique which I've used for many years myself...
Damn I hit the wrong button and concluded my above. When the temperature of the bottle to be filled is around 0° f, on a warm day, no burping is needed to get it to the original weight of the bottle. I weigh the bottles before they are used, and write that on the side, and make sure I don't exceed that. Or, if I do, I burp the excess propane to get down to the safe DOT weight.
If I recall, there is no code violation as long as the bottles are not transported. (Yeah, right!)
I’ve refilled the Coleman bottles a number of times but now I only use the ones that are made to be refilled because the half of the Coleman bottles would leak and be empty after a few weeks.
They are designed that way so you have to give coleman more money.
Nice set up
Excellent 😎
a paint marker might help you, the numbers are far less likely to rub off
I was wondering why i wasn't getting my bottles full. A video i watched another guy ., had said to hook your 20lb bottle to your 1lb bottle and start filling . he said fill until you can't hear the gas being transferring any longer the tank is full, it never fills the 1lb bottle up. (bad advice). So thank you for the tip.
Do you know the weight of the hose and filter? Thanks for the video.
Can you recommend a coupler that could go between the Flame king adapter and the braided hose adapter, for those who would prefer to use both, together? ASO, do you know of any similar type of stand, that would be compatible with a smaller, 5 pound propanr tank - or universally adaptable, for tank sizes of 20 lbs., and under? Thanks.
Every disposable relief valve I have pulled, has started to leak at some point. Good news is you can fill these without purging ANY gas. How does liquid flow into the empty tank in the first place? A difference in pressure forces fluid from the upper inverted tank to the lower tank until pressure equalizes. As mentioned you can enhance this by cooling the receiving tank to lower its pressure before you begin. But in order to keep moving fluid you need a difference in pressure. venting gas from the lower tank creates a difference in pressure, but If you heat the lower tank, its pressure will increase. Since it is upright it will force the gas on top of the liquid, back up into the upper tank, just as if you vented it. If you then cool the lower tank, the pressure once again decreases below the upper tank, which forces fluid back to replace the gas that went up. So once the scale stops increasing in weight as pressure equalizes, move the tank into a pan of hot water. After you warm it a bit, return it to the scale, or set it in a pan of cool water to speed the cooling. Each hot and cold cycle will move gas up and fluid down. Keep checking the weight between cycles until you reach the desired fill weight.
Thanks 👍
BE ADVISED that shrader (tire valve) refill valve is designed as a ONE USE valve.
Soon, VERY soon, that valve will begin leaking.
!
the flame king has a pick up tube that would vent liquid at the right level.
I use the direct connection adapter ,that way no hose to purge air from ! Freeze tank and fill to 1 lb weight .. That way less gas wasted to atmosphere !
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I read somewhere that prior to filling the one pound bottles, that you should put them in the freezer for about half an hour. Is this still true? Thx
Shouldnt you be removing that clear plastic tube on the end of the filter before connecting it? I was told that was only there to protect the tip when not in use. True or False?
Apparently filling with a filter deems it exclusive. Use a separate filter going from big tank to a heater or other appliance since flow is reversed and you'll backflush the filter contents.
For overfilling issues on the Coleman, keep in mind they all should have a safety factor and you have a over pressure purge valve (not for neglect). Also, just like all tanks that expand, everything has a lifespan and maybe it’s a sales tactic or safety concern, material thicknesses or due to lack of features Coleman sells them as disposable.
Actually, I think it might be the Vent Valve. I'm not even venting my bottles, and I just had one valve fail, never used.
@@TimeSurfer206 I only fill them maybe 1/2 to 3/4 because I have so many (before purchasing a filler). This also helps ensure I don't overfill and have to deal with a scale. I weigh one by hand and count the seconds and do them all. I need to weigh a new one and actually figure out how long to fill by time and cut back by 1/3 to make sure its backed by some scientific data even if they have purge valves.
Can't do it by time as it takes longer as the 20 pounder is depleted scale the bottles is only way to be accurate@@ProjectAnubisUSA
@@richg.2579 Ahhh, good to know. I usually only get the about 1/2 full most of the time because I use them for lanterns and I have a few of them for 3 days of use. I have a 5lb one for the BBQ.
Where did you get your stand for the 20 pounder
Is there propane now trapped in the hose since you first shut off the flow at the green tank and not at the 20lb tank?
I have had bad luck with the hoses. they fail on me. what am I doing wrong?
Is it possible to disconnect the line from the larger tank after closing both valves and using the shutoff valve on the line to vent the smaller tank? Just wondering. Great informative here. Thanks.
That's actually a really good idea!
@@youtrades Except the liquid fuel in the line would all be lost/ vented and replaced with the gaseous fuel and air purged from the tank. Then when topping off, that same mixed gas would all be forced into the small bottle first. When I refill mine, I'm not too concerned with getting a full pound, I just refill twice as many.
@@maxprophet2401 that was my first thought as well! Then I realized the second valve could be put right next to the one on top of the bottle, and the one could have a bleeder on it. Nothing would need to be taken off even! :)
On that note, would a bleeder on the valve precipitate having to have 2 valves even?!
@@youtrades It's actually a terrible idea. Venting in that way would blow all the liquid out of the hose (unnecessary danger) and replace the liquid with vapor and air making the situation much worse when you reconnect.
Great Video! Very complete! Thank you, but the cost to set it up of $300 based on your links is not realistic if you only have a few bottles to fill.
@billabram8512
I agree with you Bill , we must be cut from similar cloth, my whole reason for doing this procedure was/ is to save money. The video subtitle caught my eye:
How to Refill a 1 lb Propane Tank for 50 cents! (The Safe and Easy Way!) I believe where there's a will there is a way! Being Amish & Mennonites we tend to fabricate whatever else we need such as the stand for the 20lb bottle just get an aluminum metal frame chair and take the plastic seat off problem solved way cheaper than the Flame King kit.
I have done some research and looked at a few different options
as far as TH-cam videos this is one of the best videos I have watched on every count, including sparking due to striking ferrous metals together and proper PPE gear.)
Why did you remove the filter for the throw away bottle?
That seems to work only with USA sold tanks, the ones in Canada seem to have a 1 way valve in them that prevents refilling.
Incorrect I fill them all the time just went to mid west propane and they sell you the fittings, make it yourself
what about the weight of the hose and valve ? Won't that add a few more ounces ? Can I use a people scale to weigh the bottles ?
Is that filter bidirectional?
Neat vid. Thanks. What brand your weight scale ?
Here's a link: amzn.to/3EzO7fb
The best way to not wipe off your magic marker mark is to put clear tape over the magic marker mark.
When you weight the tank hooked up to the hose with the filter you are adding extra weight.
Let me know when you need to replace the O Ring inside the Flame King bottle. Trust me it is not easy, but I found a way. Thanks for the video!
I am a retired linoleum layer our blowtorches have refillable small tanks that have a bleeder as you are filling them you open the bleeder when you get a mist of propane from the bleeder close the bleeder and the tank is full.
OMG You're the same guy who makes ball python videos! I could tell by your voice before I even saw your face! lol
I noticed a Blue Rhino 20# propane tank. I don’t know why people buy them mainly they only fill them to 15# and their excuses is that’s it’s safer, it’s safer if they only put 5# in it also. I pay the same for 20# at a local propane store you get 5# more for same price. I would only use blue rhino if I screwed up and had to but some on a day when propane store was not open.
The disposables have a pressure release valve to prevent over filling or any other pressure related malfunction. I connect, turn tank upside down, come back later, bottle filled. Also depends on how much propane in large main tank as to how much, how fast Liguria gas is transferred from my experience
Liguria? Is that a variant of ligma?
@@specialopsdave Liguria Gas company in Italy.we call it Propane in USA regardless of who refines it
I've had one for about a year and I love it. I close the tank valve once I see it spit. Everyone is always huddling around my Mr. Buddy at the little league games lol.
What about the tare on the valve,filter and hose ? Is the tare of the tank including it all ?
Yes
What I would do is weigh the bottle without anything connected. The weight of the bottle minus the tare weight tells you how much propane is in the bottle. Let's say the differencer is 1/2 lb. Connect everything up and add as much propane to increase the scale weight by 1/2 lb. Doesn't matter about the extra weight of the hose and valve. You're looking fgor an increase of 1/2 lb in this example. There's little difference between the tare weight of hundreds of non-refillable bottles from a single manufacturer. Same goes for refillable bottles.
You can buy 4 flame king from flame king direct for 59.95 no tax no shipping, filling adabter 24.95 for 85.00 total. 3 fills on each one you have your money back and your fills are the .50 each for years , one of the few bargains left.
I have heard other say that if you freeze the bottle before refilling it, it will reduce the internal pressure and you can fill it further. Intuitively that makes sense but mathematically it seems like it would have much of an affect since in PV = nRT, T is in Kelvin and the percentage difference between 294K (70F) and 269K (26F) is not much. Has anyone tried that?
Thanks, Santa Clause! 🎅🏻
I just use a schrader valve remover, back out the valve a little.
We're you buy the attachment from 😌.
Hello everyone. First of all; Congrats for your interesting and educational content. I'm in doubt if it is Ok to use the propane filter this way because we commonly use the filter with the propane flow the oposite way towards the appliance it is connected to. I also noted that you didn't use the filter while refilling the disposable canister and don't still understand why. Your advice on this is gratefully appreciated in advance. We follow you.
So we're assuming those filters do the same job with the propane flowing in the wrong direction??
Amazon seller says the filter needed is because we use junk propane or are refilling incorrectly. The impurities f'up the catalyst in Mr. Buddy heaters, that translates to carbon monoxide. It "doesn't filter particulates." Apparently, it only removes atomize-able things that aren't propane. Using it backwards to fill bottles and then forwards to run a heater would not be good. I'd leave the filter for the catalytic heaters and do your best to prevent impurities manually. Like lightly purging lines during assembly, covering and capping fittings between uses, blowing out everything that hasn't been capped. The little plastic caps you get on a new bottle work just as well on the used ones.
so glad someone else pointed out that that filter is one way and he has it completely backwards.
@@thegreatcurtismo4329 Actually the filter works both ways but keep the refilling one for that purpose only. If you reverse it for a different purpose it will backflush any junk inside it. Also if you are concerned it has built up too much inside just reverse to atmosphere and deliberately backflush.
Why didn't you use the filter for the other canister?
I have never seen aluminum on a propane 1 # bottle threads or bottle. I have ever only seen steel bottles. And have used several brands of disposable propane.
If you are worried about wiping off your weight markings, cover them with clear packing tape.
The caps are not metal! Metal is Ferrous, a magnet will stick to it. Where a magnet will not stick to those caps.
The caps You are using are made of brass.
How long in freezer?
Did you forget to use the filter when you filled the Bernzomatic bottle?
Are you sure you can "overfill" them? I've seen other videos and I thought when it stops after 1 1/2 minute it's full. (That's what the Canadian refill video guy showed. I certainly wouldn't want it to burst, but is it impossible? how would you know when to stop. He just waited till the hissing stopped.
that’s why they have that emergency release valve , that he purges ,they won’t explode from overfill
Weigh bottle empty and write tare weight on it. Place empty in freezer, 20 lb cilynder room temp. Put adapter on 20 lb, remove empty from freezer and thread on to tank. Turn whole thing upside down and fill til you hear hissing stop. Weigh newly filled tank. If it is low, refreeze it and add a little more. I have always filled to just 1 lb using this method.
as others have said the bottle is only made to hold 1 lb of propane, so the full weight is the weight of the bottle plus 1 lb, if it is more it's over full and dangerous.
@@richardevans3084 As temperature increases, the vapor pressure increases to the point where the pressure keeps the propane from vaporizing furtther. If the heat raises the vapor pressure to about 200 psi, the overpressure valve opens and dumps excess pressure out the tank. If the pressure relief valve works, it can't explode simply by overvilling. If it can, I'd like to see a video. It can explode in the presence of a spark while venting.
I've been refiling the Colman tanks for years. No problem, as long as the tank has the little valve next to the connection valve, they can be refilled safely and purge the air with the small valve dont just fill it.
Yes just fill it, you ruin the safety vent by trying to pull up on it.
there is NO AIR to purge
Just don't over fill in the cold then put it in the sun. Very dangerous.
Why didn’t you use the filter with the non-refillable type?
nice
I make those Coleman 1 pound disposable bottles… trust me not worth the risk refilling them! Be happy the one you bought didn’t blow up in the first place!😂
So it’s completely normal for air pressure to be venting out until you tighten the allen key.
I like this setup. But you talked in length about not having any conductive clothing or things that could possibly cause a spark near this setup. Then placed the bottle on an electric scale. The vent on the flame king I believe vents at 80% fill.
Do you need a filter when using this method?
No , not absolutely necessary .... but I would never fill one up to 1 lb. , only 12.5 - 13 ounces !!
Propane is more than 50 cents per pound brother. There's no way that you can fill a 1 lb cylinder for 50 cents.
However I do like the whole video. Very well put together and very informative.
I pay $10.99 per refill of a 20lb. tank so that's about right.
you dont get 20 lbs of propane in a 20# cylinder. these days its 15#.
Hi @@ellistemple8112 If you do cylinder exchange like Blue Rhino, etc., you only get 15 lbs. However, if you own your own tank and take it to be refilled at a hardware store or RV place, you do get 20 lbs. Of course, in the video, he's got a Blue Rhino tank, so in that case you would be right, it's only 15 lbs. 👍
Before connecting the filter/hose combination fitting, weigh the bottle first then weigh again after the hose and filter are connected to get a true tare weight before filling. Prevents overfilling.
what will be the safe life span on this 1lb bottles by doing the refill method?
The Flame King bottles are refillable and have a lifespan of 12 years. There is no safe life span on the Coleman or Bernzomatic 1lb bottles. They are DOT39 containers and not meant to be repressurized. That is why there is a warning on the bottles stating federal law prohibits transporting it if refilled. You could face a $500k fine and 5 years in prison.
How long can you use a 1lb bottle for? Or how many times can you refill it?
From what I have read, you should only refill a disposable 1lb. bottle 3X three times. There are many variables however, because I live where my altitude is high and my humidity is low and the moisture inside the bottle is dry to non-existent.
If I lived back in Kansas as I used to where rust was a major problem I would not take the risks just to save a few pennies.. Same thing with sea-level and salt air.
I am graduating to Flame King refillables totally eventually since I like to be able to "legally transport" my 1 lb. LP Gas bottles..in my sport vehicles without any question marks.
Where did you get the stand for the 20 pound tank
Its part of the flame king kit.
Stand set up is on Amazon
@@sandman0917 thanks
This dude has to be from California, us in the Midwest have just been sending it for decades!
I'm confused why overfillingis the risk. I don't see how an extra 1/4 pound would be an issue to the canister. The pressure from the large tank is going to be the same when it's as you said 1/4 - 1/3 full without venting vs venting and same pressure at "full". A pressure regulator would be the risk mitigating factor, not weighing the canister. Or that is what seems more logical to me. Idk for sure though so I am asking the question.
No propane container should be liquid filled to over 80% of it's (liquid)volume capacity ever. If you get your 20 lbers refilled yourself at a propane station it will never be filled over 80%, and modern 20lb tanks have afloat valve that closes at that percentage. One danger of overfilling is that on a very hot day the pressure in an overfilled tank will become great enough to open the pressure release valve releasing propane gas to the atmosphere in an area where it might be inadvertently ignited. This would happen because the 20% of the tank that is not filled with liquid is gas and gas is compressible so it will absorb the expansion of the liquid propane in the tank up to a point without opening the PRV. If you accidently filled the tank to it's full capacity with liquid propane the liquid doea not have the ability to compress so it will open the PRV instead. The idea with the PRV is a controlled release is better than a ruptured tank but I think we can all agree we don't want either. I use to fill the coleman nonrefillable tanks and found a couple I had overfilled and been stored were bulging do to pessure buildup on a really warm day. Thankfully they didn't burst and that was wnen I started weighing tanks as in this video. I have several of the Flameking refillables and I believe they're pretty hard to overfill, but I still always weigh each one when I'm done filling them. I don't do the colemans any more (although I have filled a lot of them)because they're so much more work to fill and I myself don't like messing with the PRV valves .BY the way a pressure regulator won't tell you how much propane is in the tank, the weight of the tank is what 100% determines it for sure. This is actually a great video tutorial that explains in detail everything I learned the hard way.
Same pressure no matter what i kindah figger.
Risk is pressure build up if the filled cylinder gets warm. Let’s say u fill the cylinder on a cool morning and then haul the cylinder around in the sun. The pressure can get extreme because the liquid has increased in volume due to the warmth. And more vapor is trying to form but with less room for it to do so. In the extreme case, if one fills the cylinder so full their is almost no head-space then in warming conditions the increasing liquid volume can reach the point that the cylinder isn’t large enough. the hydrostatic pressure can get to rupture point and that is violent. This similar to water pipes freezing and bursting, but this release also spews flammable aerosol, not just pieces of metal. People can get complacent and never realize they almost had an explosion.
Propane is quite expansive in increased temperatures and it also raises the pressure. An overfilled tank could vent if it gets too warm and of course a fire hazard.
@@dogassedugly3002 Sorry, wrong.