Few world know i was a mean propane filling machine in mine high institution days in ~ Taylor Hardware. Together a result, I know a couple of things about tank tare weights (an empty tank"s weight) and also other propane lingo.

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For the last 7 year I had actually my trusty Weber grill hooked right into a 500 gallon underground tank at the home in Taylors. When I moved previously this year come an all-electric residence I had to switch earlier to a traditional 20 lb BBQ grill tank. I also considered 30, 33, 40, 60, and 100 lb cylinders, to protect against refilling together often. I discovered that new 30 or 33 lb cylinders room at least twin the price the a 20 lb, and finding lightly supplied ones ~ above Craigslist wasn"t happening.

I choose up a brand-new 20 lb tank at the house Depot because that 29.97, minus 10% off competitors coupon and also a 10% discount ~ above a gift card purchased on eBay. (Costco sells tanks for 28.99 contrasted to Amazon"s approximately $45). Now, whereby to fill it?

A little About Propane Tanks

These "20 lb" tanks space designed come take up to 20 pounds that propane. Friend may gain a pound or 2 less, depending on the temperature of the tank and also surrounding air once the tank to be filled. Cooler = an ext propane in, name is = less in. Tanks deserve to actually fit another 20% in the tank, but that extra space is design for development as the temperature rises.

In really cold winter climates, favor Canada, there may be an ext concern/rules about filling a tank come a finish 20 lbs. This is since if you leave a tank outside in really cold temps, to fill the tank when the tank is cold, and then lug it into a hot basement/garage because that a room heater, the gas will increase as the tank warms. With enough of a temperature increase, the tank"s press relief value will relax a bit of gas. This would be much less of an worry if the relief value were bleeding to outside air.


All propane tanks have a "tare weight" or "T.W." stamped ~ above the collar of the tank. Because that a grill sized tank you just calculate the tare load + 20 lbs, and that"s how much the tank must weigh as soon as it"s full. Many 20 lb tanks have actually a tare weight of +/- 17 pounds when completely empty. This means a "full" propane tank must weigh around 37 pounds.

There is also a month and also year top top the collar denote the day the tank to be made. For 20 lb propane tanks, you have 12 year from the produce date before the tank have to be re-certified with a brand-new date stamped on it. The re-certification just adds 5 years prior to having to re-certify again. The cost and also inconvenience that re-certifying nearly always outweighs the price the a brand-new tank.

Brand new propane tanks might come v air inside and need to be "purged" prior to the very first fill. Some more recent tanks, prefer Bernzomatic, will have a sticker on them saying they don"t need to be purged in ~ 6 month of the produce date.

Purging needs a unique adapter to enable a tiny amount that propane in. The press then pushes air out of a one-way bleeder valve. Purging may include another $3-4 dollars to a new tank, though some areas don"t charge, particularly if friend buy the tank from them.

The math on Refills at Costco

Internet searches suggest the following:

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

I dubbed around and the regional U-Haul place wanted $16 because that a refill. Ns remember Costco has actually a sign for $9.99 refills. I assumed I was obtaining a great deal, however it transforms out i pretty much gained no deal.


Costco in Greenville, SC is a bit deceiving due to the fact that they first hand friend a slip that claims "20 lb cylinder". Once you pay inside the receipt claims "20lb PROPANE", and also the filling print out claims "Cylinder: 20S lbs." The only defense is that the filling print out is honest and says "3.6 gallons". However, no one knows off the top of your head that a propane tank is supposed to have 4.7 gallons come be thought about "full". By saying 3.6 gallons, they space masking the fact that they put in 75%. If they want to it is in upfront they"d to speak "we will put 15 lbs of propane right into this 20 lb cylinder".

This method Costco put in 15 lb that propane.

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

or, said another way

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

The indigenous on the web forums is that the Blue Rhino and AmeriGas comparable exchange services put in 75%, or 15 lbs.

If you carry out the mathematics on Costco, it"s actually no a bad price. It"s in line, if no cheaper, than paying $16 because that a full 20 lbs. Though, Costco"s use of the "20 lb" phrase is unfortunate. I think their an inspiration is to have actually a cheaper price, for this reason members think castle are getting a good deal. Plus, by just filling 75% they do members come back an ext often, and go inside to shop while they wait.

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ConclusionIf you"re searching for the best price, owning a propane tank and re-filling it is going to be cheaper than making use of an exchange service. Together always, you salary a premium because that convenience.Ask exactly how much propane is going right into the cylinder. There must be 20 pounds going in for complete capacity.Weigh the tank as soon as you acquire home and also it need to be around 37 pounds. If that weighs 31-32 pounds then you know they only put in 15 lbs the propane.Costco"s propane price is still fair when you carry out the math.Bonus - Weber Grills

I likewise assembled the grills in ~ Taylor Hardware. Weber Grills were by far the best we sold. Reasonable care and a cover will quickly give her Weber grill 10-20 year of life. You can buy other cheap brands and they will have steel parts that rust the end in 2-3 years. You deserve to buy a sophisticated looking stainless stole brand from residence Depot and also it will likely not rust, but it will cook unevenly or the handle or wheels will certainly break off and you"ll be back to the store in 5 years for a brand-new grill.

Bonus - side Burners

I likewise helped market the BBQ grills. We offered a couple of with next burners, yet we never pushed them. Ns recall numerous conversations through customers who had actually paid more for a next burner in the past and never supplied it, in spite of their best intentions. Chances are that you will usage the next burner once or twice, therefore don"t spend the money unless you room absolutely certain you"re going to usage it