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Summer Is here and its time to go camping! I go through a lot of the small 1lb cylinders of propane. They are used for my stove, Lanterns, Heaters, etc. At  $3 to $4 a Piece, they really start to add up, not to mention that when you are done with them, they are then thrown into a landfill. No more! for about $30 you can build a refill station and refill those bottles completely for about 50 cents a bottle!

I know what you are thinking, why build this when you can buy a refill adapter ready made for your tank. I used to use one, but you can only fill your bottles about 2/3rds full. This method allows you to completely fill a bottle. much the same way as they were originally filled in the factory. and with the quarter turn valve, the refill process is quick and easy.

Disclaimer: this is the way I refill cylinders. I do not claim to be an expert, and I take no liability for mistakes you make. BE SURE TO DO THIS OUTSIDE preferably with a bit of a breeze and no near, flames, sparks, cinders, etc. Propane is highly flammable and this can be dangerous if you don't use common sense. If you blow yourself up, don't blame me!

Step 1: The Anatomy of a 1lb Cylinder

A 1lb Cylinder has a pressure relief valve. This is a safety feature that will vent excess pressure from a bottle. This is also used to vent the gas during the filling of the bottle. It looks much like a valve from a tire.

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<p>I no longer use the tire valve tool to vent the small tank. It is safer to use a needle-nose pliers to pull up the vent valve. The pressure relief valve is set at the factory. (as mentioned in some comments below.) it is difficult to get this back into the same setting and can lead to preventing the safety valve from working. the following is a link that I have since found that demonstrates the refill process with needle-nose pliers. (And yes it can be accomplished with a Harbor Freight valve adapter, but it is much easier to use an angled setup with more room.) </p><p><a href="http://www.navagear.com/2009/08/27/how-to-refill-disposable-propane-cylinders/" rel="nofollow">http://www.navagear.com/2009/08/27/how-to-refill-d...</a></p>
<p>Do not fill a bottle past 80% under any circumstances. You need the expansion room when the gas expands. Been filling them for years and learned from a propane tech the right way to do it. </p>
<p>We should look for a propane tech to clarify is. There are a lot of people claiming this but the basis is weak. Propane in a tank is liquid, and that liquid produces a vapor pressure depending on the temperature. That pressure is the same irrespective of the empty space. It's whatever pressure needed for the rest of the propane to stay liquid at a given temperature. If there is absolutely no space in a tank then I could see maybe the pressures would push funny on the tank. But I doubt it. <br><br>There could be other reasons to not overfill a tank but I don't think it's quite as clear as everyone is saying it.</p>
OK: Let me take one more stab at whether the liquid expansion is meaningful. ...<br><br>And my second stab failed. What we need is a table of the density of liquid propane vs temperature. Then, you can make the calcs for the &quot;expansion&quot; even conservatively pretending the tank walls don't also expand based on the metal heating up. Unfortunately the best nubmers I could find were only for the density at 25C and the density at -42.12C, from two different sources, suggest 580C and 580.12C. Maybe these are correct, but the difference is really low. A 3.6 gallon tank at -42.12C would become a 3.6007 gallon tank. <br><br>I think, we get a lot of anecdotes of people saying the sensor varies wildly by temperature. But, these sensors aren't perfect, and are calibrated around 25C. That could be a very good reason why they show very different numbers based on temperature. <br><br>But there's got to be an answer out there, and it frustrates me that I have no idea what exactly is the reason, and most people's suggestions have been anecdotal in explanation.<br><br>Please let me know where my reasoning has gone astray, or has just been badly explained. <br><br>Thanks. <br>
<p>I've read a few of your comments and I'd say nice job sticking with the facts on the saturated liquid-vapor lines of reasoning. I don't quite understand the data presented in your post here. You might be underestimating the amount by which liquid propane expands with temperature. We get accustom to water, for example, but without the hydrogen bonding to hold it back, liquid propane expands considerably more easily than our experiences with water. </p><p>From one source, the coefficient of thermal expansion for liquid propane is about 0.00155 / C. So, if a tank is filled on the coldest of days (-20C) here in the midwest, then on the hottest of days (40C) the liquid propane will have expanded by about 9%. If the original liquid volume was about 90% of the tank volume, it would now be about 98%. Of course, things could get worse in the trunk of a car on that hot day. To leave a &quot;public safety&quot; size margin for error, it seems the industry aims for 80% fill level. I think this is what dmmartindale was pointing out as well. </p><p>High liquid levels may also make it more likely that if some over-pressure condition forces the relief valve open, that liquid propane (now at a boil due to the dropping pressure) might get forced through the relief valve - releasing a truly unexpected volume of propane vapor that might reach a more distant ignition source or displace O2 in some confined space .</p><p>I also came across information that the pressure relief valve typically is calibrated to open at an internal pressure of about 375 psi. For saturated liquid-vapor in the tank, this pressure would occur at about 75C (165F). So much for carelessly transporting propane tanks in a closed car.</p><p>here is the source for the coefficient (thanks google): </p><p><a href="http://abiquim.org.br/congresso/cong_cd/fullpapers/p171757.pdf" rel="nofollow">http://abiquim.org.br/congresso/cong_cd/fullpapers...</a></p>
<p>Wow, Pchem, I appreciate the response! I had not considered the concept of H-bonding making water a particularly volumetrically stable state. Instead, I was mostly basing on my experience reading about metal molding and that the pouring at X degrees C vs (X+100) degrees C usually won't make a meaningful difference in volume contraction (it's all in the phase change.) That said, the liquid of metals would have a lot more effective bonding. (by the way, just to clarify, when pouring metals usually the mold is 1-3% larger than your desired object due to the metal contracting as it solidifies. Also because there's often a lot of surface finishing to do.)</p><p>When I wrote my initial comments I had been attempting to find data for the expansion of propane with temperature. The only data I remember finding was between a small celsius range, (like 20C and 30C maybe?) and so the error in the posted numbers could have been all I was seeing. I wish I had found the coefficient of expansion that you found. Because whatever I found suggested much less of an expansion. <br><br>I also went down a couple other lines that were just nonsense and I sort of wish I could edit or delete without obscuring the line of comments. That may be partly where you're confused by my data presented. <br><br>I think your analysis is very cool and I appreciate it. I do wonder if the significance of 9% would go down if you in turn also counted the expansion of the tank dimensions itself, but maybe that would be very insignificant as previously mentioned, the metal inter-phase does not have meaningful expansion at this scale.</p>
<p>I'm a gas fitter and propane tech, don't fill past 80%. They came up with that number when engineers filled a tank to 90% and then raised the temperature half a degree. The psi went from 125 to over 400. The empty space is needed to buffer the expansion. Or else you get the 'can of beans in the fire' except with propane instead of tasty beans. </p>
<p>So you may be a propane tech, but I'm still fairly confident this is a case of repeating conventional wisdom without being correct. The pressure is *the same* for a *given temperature*, expansion space or not (pretty much up until you are 99% full* [there is a case this is not true give me a sec I'll mention it later].) Let me back myself up with a table: <a href="http://www.engineeringtoolbox.com/propane-vapor-pressure-d_1020.html" rel="nofollow">http://www.engineeringtoolbox.com/propane-vapor-pr...</a></p><p><br>I think, if anything, the reason is that the hemi-sphere dome of the tank experiences a pressure that is expected and desirable to be pulling on the cylinder in a lateral way. When you fill above the cylinder where it starts doming, that means your unbalanced force is pushing on a curved service. But I also question whether this can be the case, because if it was a real concern, tilting the propane tank would be dangerous. It's obviously not. <br><br>*Here's the case where I mentioned that the pressure is not necessarily the same for a given temperature, irrespective of the volume available for gas: Technically the metal of the propane might have a different thermal expansion coefficient, *and* the *liquid* propane could have a much bigger thermal expansion coefficient, and the propane would take up more than the volume of the tank. But because interphase expansion cofficients are much smaller than interphase expansions, this is unlikely an issue unless you're at weird tank geometries or extremely full like 99%.<br><br>I hope my post isn't too long and better explains why I still don't buy the explanation given. </p>
<p>I use a very similar method to refill 1 lb bottles... right angle valve for decanting and forceps to open relief valve. Using this method its quite easy to overfill bottles and I see a lot of talk about how much to fill/overfill a bottle.</p><p>I have a very simple rule of thumb. I weighed a bottle when I bought it. It was 880 grams (31oz). (I'm from Australia and we've used metric for the last 30 years).</p><p> When I refill a bottle, I weigh it. If its close to (but not over) 880grams, then its fine. I put back on the cap and its ready to use. If it weighs more than 880g I bleed off* some of the liquid until its close to but under 880g. Job done.</p><p>In short, I bring them to the weight of a new bottle, a little less but certainly not more.</p><p>* If the valve is up, you are only going to bleed off gas. With the bottle up-ended and the valve pointing down, you will bleed of liquid, which has all the weight</p>
<p>80% full is good for me. I have a huge propane tank out side that feeds my house and they only fill that to about 80% for gas expansion and same with the bbq tanks there only about 80%. On a nice hot day propane will expand my tank will go from 80% to sometimes 93% to 97% (being the highest its ever gotten) on the gauge out side. I am NO expert but the last thing I want is a couple of one pound bottles exploding in my suv as I am driving down the road. So the harbor freight adapter will work good for me and I would recommend it to everyone else. this is a good set up but don't mess with the relief valve you should only have to purge the tank when its a virgin.</p>
<p>The pressure in the tank should be the same as a result of the gas expanding- it is driven by the vapor pressure of the liquid, since propane is liquid in your tank. So a small layer of liquid or a big layer will have the same pressure in the empty part of the tank. <br><br>There may be other reasons why they only partially fill tanks though; I don't know. </p>
<p>As long as their is some space for vapour in the tank, you are correct: the pressure is just the vapour pressure of propane at that temperature.</p><p>The potential problem is when a tank becomes full of liquid (because it was filled nearly full to start with, then the temperature increased and the liquid expanded). Once the tank is full of liquid, the pressure rises extremely rapidly with further temperature increase, since the liquid is nearly incompressible and the steel tank is nearly unstretchable. If you're lucky, the safety valve will open to release the excess pressure. This releases propane into a space where you're not expecting any, a possible fire hazard. If you're unlucky, the safety valve will stick and the cylinder will explode.</p><p>To avoid this, stations that refill barbecue cylinders put the tank on a scale, and stop filling when the *weight* rises to the correct value - one that guarantees enough vapour space remains in the tank even at higher temperatures.</p><p>What others are trying to point out is that this equipment and procedure could end up with the small tank almost entirely full of liquid, which is potentially dangerous.</p><p>- Dave</p>
<p>use a scale. weigh a factory filled tank, weigh the empty one, and weigh the one you filled. just don't put in more than 16 oz.</p>
<p>As long as *there is some space.</p>
<p>Gah! Just saw your response. Thanks Dave. This makes sense to me. It is however unlikely to be an issue unless you get to 98% or so full, I think. Give or take some tolerance on scales even 90% full should be OK. </p><p><br>My coworker suggested the 80% rule came about because propane went up in costs and people still wanted $20 refills. Blehh, who knows. <br><br>Definitively my theory of the domed top wanting axial forces..yeah...That's total BS. </p>
Just to clarify, completely full means to bring it to a full pound. There will still be expansion space in the tank.
<p>*they're only about 80% full.</p>
<p>i just ordered everything i need from amazon. my local stores don't have all the parts I need.</p>
<p>In regard to the pressure relief valve and using an angled needle nose pliers to vent the 1lbers .... the LP can create an &quot;icing&quot; on the valve seating ring - if the valve doesn't re-seat try a little room temp water .... </p>
<p>Besides being very dangerous, what you all are doing is not legal. These cylinders are just that disposable. The U.S. Department of Transportation and your local building codes to some extent do not allow the refilling of these cylinders. READ THE LABEL. There are REFILLABLE cylinders that are available and safe. Manchester Tank makes one. Don't take take a chance on severely injuring yourself. </p>
While this works -- I have one of these adapters myself -- it is very important to understand that any propane canister is only as good as its hydrostatic test results. This method should have significant safety warnings attached beyond &quot;don't blow yourself up.&quot; Ignition during the transfer process is only one concern. If the receiving canister is somehow weakened by age or handling, it could explode unexpectedly with catastrophic results. <br> <br>My local gas dealer will always check the hydrostatic test date on my 20# grill tank before refilling, and if there's any question, they will not refill the tank. They're the experts so I respect their professional opinion. I go and swap the tank out for a new one at my local orange or blue mega-store. <br> <br>Pressurized, flammable gas is nothing to fool around with, and any time one refills a container under pressure without a way to measure the resulting pressure of the container, especially in reference to its maximum safe internal pressure, could create a massive safety hazard. <br> <br>Yes, perform this at your own risk, but understand that the larger tank could impart a significant amount of pressure on the smaller one, beyond its capacity. This could create a timebomb in a 1-lb propane canister.
This is incorrect. <br>A bulk tank does not have greater pressure than a 1lb canister, <br>and can not possibly impart excessive pressure to it. <br>Also, your local gas dealer is *not* an &quot;expert&quot; <br>but simply obeys the law which mandates the expiry date for any inspection. <br>Checking that date gives him no information <br>regarding possible handling damage, etc. <br>Safety is Priority One, <br>but ignorance is a poor guide.
I appreciate the care with which you crafted your response. You clearly know lots about me from a few paragraphs. I especially liked the part where you called me ignorant...<br><br>I'm afraid you missed the point of my comment: to try to impress upon readers the idea that this is potentially a very dangerous process. The fact that my local gas dealer actually follows the law makes them far more expert than most. They do also inspect the condition of the container and will not refill a tank with visible condition issues. Forgive me for not making clear that the &quot;any question&quot; reference could also include a condition check. <br><br>I've seen the 1-lb tanks take more fuel from a 20-lb tank than they are rated to hold, so perhaps I used a term that's not scientifically precise, but my goal here is to use terms that get the point across rather than precise use of scientific jargon that could cause confusion. <br><br>Sometimes an idea is conveyed more effectively with simpler words.<br><br>Lighten up, and next time try to provide criticism that's more constructive than negative.<br><br>Safety third!
&quot;Ignorant&quot; is not an insult,<br>but rather &quot;a descriptive term that gets the point across.&quot;<br>Please don't blame people for reading the words you post<br>rather than the meaning which you fail to state.<br> <br>Ideas tend to be conveyed by accurate words.<br>It's difficult to correct incorrect information without using negatives.<br>Don't be defensive, and next time post accurate information.<br> <br>Safety first!<br>
Well, I'm pretty sure you intended it as an insult, but it seems you preferred the way I phrased it instead. I'll take that as a backhanded compliment. It's curious that nobody else in 15 months found my comment to be so egregious to warrant a correction until your castigation finally set me straight. <br><br>The meaning isn't just in the words themselves but in the spirit of the message, as well. It's absolutely possible to address what you perceive to be inaccuracies without being negative, but only if you choose to do so. Going negative is the cheap &amp; easy path, but it's more of a challenge and ultimately more satisfying to be supportive and constructive. I'm satisfied, you just seem negative.<br><br>I'm trying to be nice, but you're not making it easy. So, good luck with your precision issues. I'm not sure why you decided this was a battle you wanted to fight, but this isn't the hill I choose to die on, so it's all yours. Enjoy your pyrrhic victory.<br><br>And I really did mean safety third. Look it up...
I might point out that ignorance is a lack of knowledge or imformation and stupid is an inability to comprehend. Therefore there its not an insult to point out thatbthat someone is ignorant, as we are all ignorant about something.
<p>GeeDeeKay,</p><p>Aside from the exchange between you and shascho, I am grateful for your reference to Safety Third! It made me look it up, and I am glad I did. For anyone else who would like to read it direct from the source, here is a link to a letter about it by the man himself, Mike Rowe:</p><p>http://www.ishn.com/articles/93505--dirty-jobs--guy-says-safety-third-is--a-conversation-worth-having-</p>
Alrighty thn, GDK.<br>If you choose to interpret my words <br>in ways that I have explicitly denied, <br>that's your choice and out of my hands.<br>Seems like a lot of writing for such a trivial offence,<br>but it's as big as you want to make it, I guess.<br> <br>I stand by my corrections.<br>You stated that<br>&quot;the larger tank could impart a significant amount of pressure on the smaller one, beyond its capacity.&quot;<br>but this is simply not the case.<br>Cylinder pressure does *not* increase with size.<br> <br>If you choose to criticise an instructable<br>you should first make sure your criticisms are accurate.<br><br>Safety First, and peace out!
<p>Correct:The only thing you could possibly do is if you vented it and filled it all the way to the top and warm temps expanded gasses to the point of the relief valve purging.</p>
<p>I believe after filling many squat tanks it's not possible to overfill unless you vented at the relief valve.I always end up with 2/3 of a bottle (chilled squat bottle) Gas liquifies in the chilled squat bottle I assume.Correct me if I'm wrong.</p>
<p>DO NOT FILL YOUR PROPANE CYLINDERS ALL THE WAY!!</p><p>From AmeriGas Propane:</p><p>&quot;A propane container absorbs heat directly from the surrounding air. </p><p>It&rsquo;s not uncommon for a container&rsquo;s pressure to change. Propane liquid can increase more than 50 pounds of pressure or more in the course of a day, without an appliance operating. Propane liquid, like water, will expand when heat is added to it. </p><p>Containers are generally filled to about 80% of their capacity to account for effects of pressure and temperature. </p><p>This leaves space above the liquid for the propane to expand freely as temperatures change without danger of the container becoming over pressurized.</p><p>A propane container that is filled beyond the fixed maximum liquid level gauge may be at risk for an unintended propane release.&quot;</p><p>Propane expands at nearly 17 times greater than water, displaces oxygen and is an asphyxiation hazard if inhaled. Propane is odorless and colorless. If you have a 1lb. cylinder releasing excess pressure in your vehicle on your way to a camp site, you won't know it, and you and your loved ones will likely not make it to your destination.</p>
<p><em><strong>This is a dangerous procedure</strong></em>: This is an instructable on how to overfill a tank! Completely filled cylinders are dangerous as they don't have room for expansion once the temperature increases.</p><p>Propane/butane <em><strong>approximately</strong></em> liquifies at 32 psi at 20 &deg;C (68 &deg;F), and 320 psi at 55 &deg;C (131 &deg;F). That's a 10x increase in pressure for a 23 &deg;C change in temperature. <strong><em>Please be careful.</em></strong></p><p>Just top it up by weight. Check the weight on the label and never exceed that rating. And if you happen to overfill it, just reverse the process (big tank right side up).</p>
<p>The plumbing above works. Only thing I did different was use a 1&quot;-20 cylinder thread and soft nose excess flow POL with handwheel instead of the male POL fitting to 1/4 MIP above (top right in illustration) (Mr Heater sells them and Made in USA). The 1/4 street elbow was also changed to one end male one end female to accommodate !&quot;20 excess flow POL. With the POL you can slide it into position and tighten without rotating entire fitting for easy alignment. I also don't mess with the relief valve, instead buy a pair of &quot;curved&quot; locking forceps (like medical) and pull up on the pressure valve (as described with vent tool above) while filling until you see a small burst of liquid vapor. The 1 lb bottles finish out within 2 oz. Be sure to use YELLOW thread tape designed for gas fittings. :)</p>
<p>Excellent modifications :-) You should post a pic of your setup :-)</p><p>I also went and changed up the text in my original instructable regarding venting the tank. some people don't read the stickies in the comments.</p>
<p>Although too scared to do myself, but VERY nice! Do you know a good valve to stop the camp tanks once they are only used partially from expelling the rest of their gas ? </p>
<p>when you unscrew the 1 pound cylinder the valve should close automatically if it leaks gas you should throw the tank out.</p>
<p>For those of you so called &quot;experts&quot; it is clear that being &quot;certified&quot; has also Brainwashed you into believing that what you are taught is the only way. It is clear that you have been taught how to also not think for yourselves.</p><p>If you read the label on the bottle you will see the weight of the gas inside the cylinder. here in Australia it is 426g so there is just under 1L of propane in the cylinder. I have been filling these cylinders for around 2 years now. </p><p>What I will do is exactly what thedustycelt has shown. Before and after I have finished filling the cylinder I weigh it every time and I get a weight change of 400-420g in the cylinder. This is the 80% mark that you all bang on about with your wasted time becoming &quot;certified&quot;.</p><p>If I was to buy new cylinder every time @ $10 a go, the cost of using these would be beyond reasonable. I see it as a way camping and chain stores gouge you for the convenience of having a portable gas cylinder. I also refill my regular cylinders myself using an adapter mounted in my car and go to the local service station, a camping store will charge $28 to refill a 9kg bottle a 9 kg bottle will hold 18L of gas here in Australia gas is currently $0.74/L there is an immediate cost saving. there is an even bigger saving with the 45KG bottles a local gas supplier charges $130 for a full cylinder. I can refill the same cylinder for around $67 as fuel prices fluctuate this changes. </p><p>I don't know about you but and extra $60-$70 in my back pocket is worth the trouble of a small bit of math and a little plumbing. Two refills of the 45kg bottle and I have paid for the filling hardware, so it pays for its self very quickly.</p><p>The gas at the service station is more refined than the BBQ gas your local camping and hardware stores sell, so its better for your equipment</p>
<p>When using dichotomous cooling of the slave and donor tanks, it is possible to overfill the 1lb tank using the conventional adapter, that's why a scale should be used. The connection fittings are best if bridged with a flexible hose which then allows you to float the receiving 1lb tank on the scale. Once you place the bottle on the scale and zero it out, you can then monitor the net weight as the bottle fills and halt the process at 16.4 oz. Then confirm the gross weight which should be the sum of the tare (the weight of the empty bottle), and the net. If it is over, you then use the pressure relief valve to adjust to your target volume.</p>
<p>I just use the HF refill kit but leave the 1lb bottle on the 20lb donor tank for about an hour and I beleive this fills it to about 90% +.I have had no bulge problems and refill most bottles about 6 times before they decide they no longer want to be refilled.Also helps to warm the larger donor (grill tank) and keep the smaller 1lb tanks cold before you refill.Good luck and keep refilling......</p><p>%</p>
Thank you all very much. I just started using a Buddy heater in my truck and I asked several people when I was buying them and was told no way are they refillable. I've probably thrown away a dozen cylinders. Now I know better.
<p>Overkill. The Harbor Freight bottle refill kit works really well, and will refill the &quot;disposable&quot; bottle as full as the elaborate setup. The limiting factor with either is the pressure in the donor bottle, which is a function of how full it is and temperature of the bottle.</p><p>http://www.harborfreight.com/propane-bottle-refill-kit-45989.html</p>
<p>I'm with you. 1/2 full, 2/3's full... who cares. The entire reason I started using the refill adapter doohicky was so I didn't have to buy a new dang 1 lb tank for my grill whenever it ran out. Plus the thought of throwing away steel containers simply made no sense - since they are good for many refills!</p>
<p>the trouble with the harborfreight valve is that you can not get to the relief valve to vent the bottle as you fill it.</p>
<p>I forgot. The recipient bottle can be filled to a higher pressure than the donor bottle with the use of a pump. Which is, of course, prohibitively expensive for this use.</p>
<p>I was pretty interested in this instructable until I started reading <br>the comments. I found the barbed comments between you guys to be <br>off-putting, and will look for another source of information on this <br>subject. <br><br>Food for thought... If you have a pissing contest, <br>and fill your thread with barbed comments, you're likely to lose your <br>potential audience. I'm disappointed that I wasted as much time as I <br>did reading comments that had little to no informational value to them.<br><br>Have a nice day, and thanks for the Instructable.</p>
<p>I've had great success using the cheap Harbor Freight style adapter. What has made a HUGE DIFFERENCE, is to first FREEZE THE 1lb TANK. I think I saw this in a YouTube video somewhere. Someone smarter than me can probably explain why this works. </p>
<p>Could be DANGEROUS!</p><p>For those of you that use Propane powered stoves, lanterns <br>&amp; heaters, there is finally a solution to having to keep buying those <br>disposable one pound propane cylinders. </p><p>Did you know? ...</p><p>Over 30 million empty 1 lb. non-refillable cylinders end up <br>in landfills every year.</p><p>The cost of a non-refillable cylinder is about 6-7 times the <br>actual cost of the propane in each cylinder.</p><p>A distributor called 'Flame King' is now selling DOT <br>certified refillable one pound (16.4 oz) cylinders and 14.1 oz cylinders.</p><p>They sell a complete refill kit that includes a 20 lb nurse <br>tank, the refill adapter/valve, and two refillable cylinders. </p><p>The cylinders are constructed like a miniature 20 propane <br>tank from heavy gauge steel, with a solid brass threaded top, and come with a <br>one year warranty. </p><p>No more buying disposable propane cylinders that will end up <br>in the land fill for me boys, I'll save a bundle being able to refill these <br>instead of buying the disposables ... </p><p>For more information go to go to their E bay site <br>[URL=&quot;http://stores.ebay.com/Flame-King-Cylinders/Refillable-Cylinders-/_i.html?_fsub=6719314015&amp;_sid=1182848655&amp;_trksid=p4634.c0.m322&quot;]http://stores.ebay.com/Flame-King-Cylinders/Refillable-Cylinders-/_i.html?_fsub=6719314015&amp;_sid=1182848655&amp;_trksid=p4634.c0.m322[/URL]</p>
I always thought it is a waste to use a nice little bottle and then throw it out. Although those little propane tanks only cost 3-4$.
<em><strong>Loosening the pressure relief valve with a valve core tool (Step 3) or any other tool to bleed the cylinder is a bad idea.</strong></em><br> <br> The depth to which the valve core is screwed into the body determines the preload on the spring and thus the pressure at which the valve opens.&nbsp; There is no positive &quot;stop&quot; as in a tire valve core.&nbsp; The correct depth is determined by calibrated factory tooling, which the average DIY person doesn't have.&nbsp; If the valve core is screwed in too deep, the relief pressure setpoint may rise to a dangerously high value.&nbsp; It is much safer to use a pair of needle nose pliers to grip the end of the relief valve core pin and pull it outward to open the valve.&nbsp; Bent needle nose pliers are best, as they help keep one's hand out of the path of the icy cold LP gas discharge.&nbsp; Wear safety goggles while doing this.<br> <br> When the pin is released, it will snap into position and (hopefully) re-seat without leaking.&nbsp; If it does leak, it may be due to freezing of the elastomeric valve seat, inaccessible at the bottom of the valve body, inside the cylinder.&nbsp; Wait a few seconds for it to warm up, then try pulling the pin for an instant and letting it snap back.&nbsp; If, after four or five attempts the valve doesn't seal, it may mean the valve seat is worn out and unusable.&nbsp; Set it aside outdoors, away from ignition sources, where the propane can leak away harmlessly, and when it is empty, discard it.

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