Few human being know i was a mean propane filling maker in my high school days at Taylor Hardware. Together a result, I recognize a couple of things around tank tare weights (an empty tank"s weight) and other propane lingo.

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For the last 7 year I had my trusty Weber grill hooked into a 500 gallon secret tank in ~ the house in Taylors. Once I moved previously this year to an all-electric home I had to switch ago to a traditional 20 lb BBQ grill tank. I additionally considered 30, 33, 40, 60, and 100 pound cylinders, to prevent refilling together often. I discovered that brand-new 30 or 33 lb cylinders room at least double the price the a 20 lb, and also finding lightly provided ones top top Craigslist wasn"t happening.

I picked up a brand-new 20 lb tank in ~ the home Depot for 29.97, minus 10% off rivals coupon and a 10% discount on a gift map purchased on eBay. (Costco selling tanks for 28.99 compared to Amazon"s around $45). Now, where to to fill it?

A tiny About Propane Tanks

These "20 lb" tanks room designed come take up to 20 pounds of propane. Girlfriend may obtain a lb or 2 less, relying on the temperature the the tank and surrounding air as soon as the tank to be filled. Cooler = more propane in, hot = less in. Tanks have the right to actually fit an additional 20% in the tank, but that extra room is design for growth as the temperature rises.

In very cold winter climates, like Canada, there may be an ext concern/rules around filling a tank come a complete 20 lbs. This is since if you leaving a tank external in very cold temps, filled the tank once the tank is cold, and also then bring it right into a hot basement/garage for a room heater, the gas will broaden as the tank warms. With sufficient of a temperature increase, the tank"s press relief worth will relax a bit of gas. This would be much less of an problem if the relief value were bleeding to exterior air.


All propane tanks have actually a "tare weight" or "T.W." stamped on the collar of the tank. For a grill size tank you simply calculate the tare weight + 20 lbs, and also that"s exactly how much the tank should weigh once it"s full. Many 20 lb tanks have actually a tare weight of +/- 17 pounds when completely empty. This means a "full" propane tank should weigh about 37 pounds.

There is also a month and also year ~ above the collar indicating the date the tank to be made. Because that 20 lb propane tanks, you have actually 12 years from the to produce date prior to the tank must be re-certified through a brand-new date stamped on it. The re-certification just adds 5 years before having come re-certify again. The cost and also inconvenience the re-certifying almost always outweighs the price of a brand-new tank.

Brand new propane tanks might come through air inside and also need to it is in "purged" before the first fill. Some more recent tanks, favor Bernzomatic, will have a sticker on them speak they don"t need to be purged within 6 month of the produce date.

Purging needs a unique adapter to enable a tiny amount of propane in. The push then pushes air the end of a one-way bleeder valve. Purging may add another $3-4 dollars to a new tank, despite some places don"t charge, particularly if you buy the tank from them.

The math on Refills at Costco

Internet searches imply the following:

1 gallon that propane weighs 4.2 poundsA "full" 20 lb cylinder should have 4.7 gallons or propane in it

I called around and the local U-Haul location wanted $16 because that a refill. Ns remember Costco has a authorize for $9.99 refills. I assumed I was getting a good deal, but it turns out i pretty much got no deal.


Costco in Greenville, SC is a little bit deceiving due to the fact that they an initial hand girlfriend a on slide that says "20 lb cylinder". As soon as you pay inside the receipt states "20lb PROPANE", and the filling print out states "Cylinder: 20S lbs." The only defense is that the filling print out is honest and also says "3.6 gallons". However, nobody knows off the height of their head the a propane tank is an alleged to have 4.7 gallons come be taken into consideration "full". By saying 3.6 gallons, they space masking the fact that they put in 75%. If they wanted to it is in upfront they"d to speak "we will put 15 lbs that propane right into this 20 lb cylinder".

This way Costco put in 15 lb the propane.

3.6 gallons / 4.7 gallons = 75% the the normal fill.

or, said another way

(4.2 pounds/gallons) * (3.6 gallons) = 15 pounds

The word on the web forums is the the Blue Rhino and also AmeriGas comparable exchange services placed in 75%, or 15 lbs.

If you do the mathematics on Costco, it"s actually no a poor price. It"s in line, if no cheaper, 보다 paying $16 because that a complete 20 lbs. Though, Costco"s usage of the "20 lb" phrase is unfortunate. Ns think their an inspiration is to have a cheaper price, for this reason members think castle are acquiring a great deal. Plus, by only filling 75% they do members come back more often, and also go within to shop while castle wait.

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ConclusionIf you"re searching for the best price, owning a propane tank and also re-filling the is walking to it is in cheaper than using an exchange service. As always, you salary a premium for convenience.Ask how much propane is going right into the cylinder. There should be 20 pounds walking in for full capacity.Weigh the tank as soon as you get home and also it should be about 37 pounds. If the weighs 31-32 pounds climate you understand they just put in 15 lbs that propane.Costco"s propane price is tho fair when you carry out the math.Bonus - Weber Grills

I also assembled the grills at Taylor Hardware. Weber Grills to be by far the finest we sold. Reasonable care and also a cover will quickly give your Weber grill 10-20 year of life. You have the right to buy other cheap brands and also they will have actually steel components that rust out in 2-3 years. You can buy a fancy looking stainless steel brand from home Depot and it will likely not rust, but it will cook unevenly or the manage or wheels will break off and also you"ll be ago to the save in 5 years for a new grill.

Bonus - side Burners

I additionally helped offer the BBQ grills. We offered a few with side burners, however we never pushed them. I recall numerous conversations with customers who had actually paid more for a next burner in the past and never offered it, regardless of their finest intentions. Chances are that you will use the side burner as soon as or twice, therefore don"t invest the money unless you room absolutely certain you"re walking to usage it