what's the proper way to store a propane tank (extra)

I did some quick calculations and a full 20# propane tank at 70 degrees will be at about 145 psi. At 100 dge F that tank will be around 170 psi. Typically the tank pressure relief valve, which is opposite the normal hose connection, will release excess pressure at 200 psi.

Note I said a full tank, most places are not really filling a tank, that is putting 20# of propane into the tank. Most are putting in about 14# to 15# of propane. It isn’t due to the pressures, it’s simply a way to make more money.

A tank weights about 17# (it is stamped around the collar as “TW”) so with 20# of propane the total weight will come in around 37#

Ok first companies are supposed to only put 80% of what a tank is supposed to hold , this is a safety factor. Second this is coming from a propane truck driver , at 60 degrees propane has expanded as much as it is going to expand. Somebody want to check these facts i am fine with that...Stan

My tanks weigh about 18 lbs empty by measurement. (I'll look for the TW stamp).

My propane supplier currently is a local Valvoline oil change place. They charge me by the pound for what they put in, not some standard per tank price, so they have no incentive to underfill. The last time I weighed a full tank it was 37.3 lbs, so they came really close to putting 20 lbs in a 20 lb tank that time.

Ace Hardware is selling 20 lbs, but I don't see what the person is doing, it's on a scale. Can a 20 lb. tank be overfilled?

You've got me curious, I'm going to weigh it! More to come

edit yep, they skimmed. Only 16.5 lbs of propane. Isn't human nature rather despicable when it's not kept in check? Next time, I'm going by the gallons reading on their tank. 20 lbs is 4.6-4.7 gal.

Perhaps it is your choice of words but it may be the reason your truck driver is a truck driver!

20# of propane is about 4.6 gallons. The tank can actually fit another 20% or the equivalent of about 5-1/2 gallons. That difference between 4.6 and 5.5 is about 20% which is for expansion. But it is perfectly OK and legal to put 20# or 4.6 gallons of propane into that tank!

Is the hardware store conducting themselves per industry standard? Because they did only fill 16.5 lbs, but not 15 like a Blue Rhino.

Or is it the scene from the Sopranos where they are monkeying with the scale.

Answers online are all over the place, but I'm leaning towards 20 lbs is safe.

A tank can conceivably be overfilled eating into that 20% space. High temperatures could result in some blowoff due to excessive pressure. The relief valve would reseat as pressure got below 200 psi. BTW, tanks are white to minimize temperature changes when tanks are stored in the sun.

Weighing it is the best thing and most home scales will be close enough. For various reasons, mainly to increase profits, the “exchange” places only put in 14# to 15#, so a tank will come in around 31# to 32# when supposedly “full”. U-Haul rental places, even Costco, same way. This keeps the price to the consumer down and the profits up A place like Tractor Supply, some actually do refills, not exchanges, charge by the gallon. Mine charged $3.99/gallon a month ago.

One more thing John, as I think you live in PA, they are not supposed to charge you sales tax on a propane refill. It is considered “recreational use” and exempt from sales tax.

I only paid $9 per tank with a Groupon. The $ amount isn't enough to get mad about. But I am surprised because this store sells thousands upon thousands of Groupons. And the guy with the BMW paid $19x3 and likely each tank he got 16.5 lbs, not 20....I bet the employee is only doing what they were told to do...

edit went back to read the Groupon: "20 pound propane tank refill"

Taken literally, they're not saying 20 pounds of propane, they're describing the tank hahahahahahah

But you've opened my eyes, to say the least! I did know about the 15 pound exchange...

Regardless whether it's a BBQ cylinder or a 1000 gal tank you fill to 80%. Some tanks we could fill to 90% in the winter. It's not about being cheap. It's about safety (expansion of the gas) and liability. It's the same reason non ASME tanks are supposed to be re-certified every 12 years. In most cases you pay by the amount of propane so if they put in 4 gal that's what you pay for. Yes some of the tank exchange places might scrimp a little but I always own my own tanks so I've never dealt with that. The tank should have a gauge and/or a bleeder valve. Gauges are mechanical and can be wrong. The bleeder valve is much more reliable as it is a simple tube that allows the tank to spit propane when the propane reaches a certain height in the tank. Most BBQ tanks have just the bleeder which spits when tank is at 80%. Depending on the speed of delivery and when the dispenser is shut off you actually end up over 80% in most cases. Yes you could fill to 100% but do you really want the pressure relief valve blowing on your porch and if the valve fails do you want a tank rupture for that 1 extra gal of propane and if there is an ignition source nearby an explosion? Propane is virtually the same as natural gas and the boom when it goes off just as bad.

I'm talking about what is commonly called a "20# propane tank".

If we remove the valve on the top of the tank, position the tank upright, and fill it to the very brim of the opening with water, it will hold about 5.6 gallons. 20# of propane is about 4.5 gallons. That's a volume measurement, a gallon of propane is the same as a gallon of water. Simple math says 4.5/5.6 = 0.80 or 80%. The other 20% is for expansion and is termed "ullage" or “headspace”.

OK, what does that really mean...lets take that tank and carefully fill it with water, measuring as we go to only put 4.6 gallons of liquid into the tank. It won't be full, it will in fact take about another gallon of water to fill it to overflowing.

Today, “exchange" type propane tanks, like Blue Rhino, are often only filled with 15 pounds, or about 3.5 gallons. Buyer beware!

What does Blue Rhino say? I'll quote

"How much propane does Blue Rhino put in its tanks?

Inflationary pressures, including the volatile costs of steel, diesel fuel, and propane, have had a significant impact on the cylinder exchange industry. In 2008, to help control these rising costs, Blue Rhino followed the example of other consumer products companies with a product content change. We reduced the amount of propane in our tanks from 17 pounds to 15 pounds.

To ensure our consumers are properly notified, Blue Rhino clearly marks the amount of propane contained in our tanks, right on the package. Blue Rhino also notes the amount of propane contained in our tanks on our display signs."

In most cases, should you find a true propane dealer that can deliver propane as well as refill 20# tanks, you will get a true 20# (or close to) and walk away with a tank that weighs about 37-1/2#. And you can likely do that for $20, instead of the $25 for a Blue Rhino tank that at best, is partially filled.

I haven't seen it mentioned here, but I remember being told many years ago that propane cylinders should not be stored in a closed area, particularly a basement or crawl space. Propane gas is heavier than air, and if there is a small leak the vapor will pool on the floor and slowly rise if there is nowhere for it to escape. If it keeps leaking and finds an ignition source, like a pilot light, it can make for a bad day. A shed or garage is *probably* ok since there will be doors or windows that aren't completely airtight and would allow the vapor to escape. I always kept a spare, filled tank on hand when I had a propane bbq grill, and I always left it outside next to the house with a loose plastic cover over it for weather protection. Seemed safer than keeping it in the garage or house.

Do you guys just sit around the house all day, worrying about this stuff.

Tank is empty, get it filled, done. Propane in that amount is so horribly expensive that I need to worry it? Move on to more important items in your life.

This reminds me of the other topic here about GPS accuracy. If the unit takes me there. Done. Is it within an millimeter - don't care, it has done the job I bought it for. Remember paper maps, they were less accurate and not updated monthly either.

See https://www.amerigas.com/about-propane/propane-safety/tank-s...

They don't allow just any truck driver to drive a propane truck i am pretty sure.

Here in PA, in general they have Class A CDL with Hazardous, Air Brake and Tank Endorsements.

The Class A CDL is for pulling a trailer over 10,000 lbs, I've seen plenty of straight trucks delivering propane that would only require a Class B license, along with the haz-mat, and tanker, and depending on the truck, air brakes.

I had all of that when I delivered fuel oil (home heating) for a living.

Another ex-propane (Hank Hill) here.

Keep the tank upright don't lay them down sideways!!!
Only exception fork truck tanks 33# & 43# they are designed
to be laying sideways with the relief valve at the top.
Outside in a shed is ok - DO NOT KEEP THEM IN THE HOUSE OR GARAGE!

Don't smoke (duh!) while hauling them in the car.
I heard a story of some idiots Huffing propane out of a garbage bag - one of them decided he wanted a cigarette (BOOM!)

80% as others have stated is the normal fill volume. Using the "spit/bleed" valve is a normal way to fill and or by weight.
Liquid starts coming out - shut the valve - and kill the pump!

Blue Rino does short the fill = for "SAFETY".

https://www.kampspropane.com/wp-content/uploads/2017/12/Prop...

Crew

Good to know.

I have found that a plastic milk crate type container holds a 20# tank nicely without adding too much additional weight. It holds the tank upright and except in perhaps a panic stop, keeps it from rolling around.

Scouts like to have them in crates for storage, movement, and especially at campouts so they don't tip over. Unfortunately not everyone follows the rules.

type of thinking actually allows for marketing to be effective in so many ways that would not have worked 25 years ago.

Half gallon OJ is 52 oz. It used to be 59 oz. There was a time when a half gallon was in fact 64.

I was just talking about this with my boss this week as the subject was gasoline, increasing taxes, and decreasing prices. I said can you imagine if at the pumps we actually got 81% of a gallon, the way we do with OJ and propane? I'd suggest the industry try it, because people don't worry about matters such as these. Heck how many people today even know what a gallon is? We learned it in HS physics, but I don't now if that's even taught today lol

As far as sitting around the house all day, I heard somewhere that many folks have a job not 100% remote, as a matter of fact, the opposite, 100% in the office (this is another topic in itself as many colleagues are permanent WFH [when 2019 they came in like everyone else], again, haves, and have nots, by design hehe).

I will close with my 02 ymmv

The newer Costco's all charge based on how much you put in, not a flat rate. However, if it's a new tank, they have to purge it first to get the air out.

I always stored spare tanks in the shed. No shed is completely sealed, plus propane is heavier than air and will settle to the floor and flow out gaps under the door and other gaps.

In Canada, the propane people all must be trained, to properly handle the tanks. Tanks have to be retested here every 10 years.

Here in the USA tanks are deemed good until 12 years after the manufacturing date stamped in up top. Don't know the drill after that, as recertification seems to cost about as much as a new tank and I've never had it done.

We still have to buy a new tank, but the old tank goes to a propane supplier or tank company. It gets recertified and a new valve is installed. It's also stamped with the new expiry date. You'll often see a new tank with as many as three dates.
No propane refill place is allowed to fill an expired tank.

I had an expired tank 10 or so years ago. Took it to a local Amerigas supplier and asked what it takes to re-certify it. Don't remember the cost but it was considerably cheaper than a new tank. Guy took it in the back room for a few minutes and brought it back out with a new date stamp on the collar. Guessing maybe they just pressurized it and checked for leaks, but I didn't watch the process.

There are three different kinds of methods outlined below. Note that the two pressure methods, one with water and one with air, give a 10 year recertification. The third and last method mentioned, simply a visual check, only yields a 5 year recertification. The visual test is generally done most frequently due to the specialized equipment needed for the pressure tests.

External Visual Method

Finally, the simplest test that can be done to recertify a propane tank is the external visual test.

This is normally only done on propane tanks that appear to be in excellent condition and have no rust or scratches on the cylinder.

During an external visual test, a certified inspector will look for any damage including; bulges, rust, cracks, damage to welds, heat damage, or fire marks.

They will also pay close attention to any kind of corrosion like rust or pitting. They will even look at the areas around the foot ring and collar.

Any DOT approved propane tank must have a foot ring, a collar, and a valve cover.

The valve will also be checked for any defects or issues with the pressure relief valve.

If the valve is an issue the company doing the recertification can normally replace it for a fee.

An external visual test will only certify the tank for 5 years.

Those old expired tanks make great burn barrels, especially the larger ones. Just cut the top off with a torch.

They are so expensive, would it make more sense to do Blue Rhino in those cases of expiration...as mentioned I did manage to get a new one $39 a couple months ago but they tend to go for $57 (they were $37 2020 or so)...

I think some years ago when my filling place pointed out my tank was expired they also mentioned that it lacked an OPD. If I understood (maybe I did not) that meant it could not be given a recertification that would let them fill it.

Or have USA sold 20-pound tanks had OPD routinely for way back?

For tanks from 4 to 40# capacity, OPD valves have been required in the US since 1998. They are also easy to recognize due to the triangular shaped valve wheel. A cheat sheet can be found at https://www.nfpa.org/-/media/Files/News-and-Research/Fire-st....

Halfway up a mountain, We use propane here for everything.... Nearest LP Gas lines are miles away... downhill...

Propane companies here will only fill an exposed tank to 80%...
A totally Submerged tank will be filled to 90%... Occasionally 92%.... if it is shielded by plants....

I was told this is due to exposed tanks are subject to more expansion due to direct sunlight... (Also why they are painted silver, or white: to reflect sunlight)... Storage of small tanks assume it is being stored in direct sunlight.... so 80% is 'full'...

Happened to me at U Haul, and the guy was polite he said he couldn't fill it, but I could go to Lowe's and exchange it. Then, when that tank ran out, U Haul would be able to refill it since it was recertified. Blue Rhino claims this is why they gouge so intensely.

But think about it....they are assuming every tank they take needs to be recertified, and charge for it. But that's not really the case, if it were, they'd be OOB. Great business model.