# Stop Getting Ripped Off by Propane Exchanges.

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It's Grilling season again, and like most people I can never remember how much I used my gas last season.

There are a couple of ways to check the Propane level in your tank, one relies on pouring water on a tank, but that will only work in the right weather, and others require the purchase of a (relatively inexpensive) gauge.

If you don't have a gauge on your tank (like me), and need to know how much you have left, then this will surely help.

You will need :-

your gas bottle

a bathroom scale

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## Step 1: Locate Your Bottle.

My bottle is a standard 20LB gas bottle from an exchange. There are a couple of things to know about bottles, but for now, just know that this is what you're looking for.

## Step 2: Make Sure the Gas Flow Is All the Way Off.

This is very important. Propane bottles have safety mechanisms in place, but always make a habit to turn off the gas. Turn clockwise all the way until it stops. Most, like mine have indicator arrows, but clockwise closes it just like a faucet.

## Step 3: Disconnect the Cylinder

Gas bottle, cylinder, tank... whatever they call it in your neck of the woods.

Even if the gas hose is long enough to reach, disconnect the hose to allow removal of the bottle.

## Step 4: Check Tare Weight.

Tare Weight is the weight of the gas cylinder alone without any gas added to it.

It will be stamped into the collar of the tank along with lots of other info, but the only thing I care about when I read this is :- TW 17.5 LB.

Yours may say T/W, or T.W. and may be difficult to read due to many years of paint build-up like mine is.

## Step 5: Tare Your Scale.

that means make sure that your scale reads 0.0.

Typical scales if they're digital will auto tare, or have a "tare button that you have to press, but mechanical/analog scales often have a tare knob that you turn to set the scale to 0.

Different floor coverings can mess with the measurement, so make sure you're weighing on a hard, level surface.

## Step 6: Weigh Your Bottle.

Weigh the gas cylinder, and subtract the tare weight.

Mine weighs 23LB, and has a Tare Weight of 17.5LB

That gives me a total of 5.5LB of gas left in the tank.

This is a 20LB tank when full, which means I have 5.5/20, or just over 1/4 of the tank remaining.

Knowing this means that I don't need to exchange my bottle yet, or if I take it to get it filled, that I know they will only be able to put around 14LB in the tank without even allowing for expansion.

Things to know:-

Most exchanges only have 15LB filled bottles, so your 20LB bottle will only be 75% full for the exchange price, and you don't get credit for any gas left in yours.

If you plan to get your bottle refilled, know how much you're buying. Some places offer flat rate filling, and typically don't account for what was in the tank to start.

Know the age of your bottle. On the collar there are dates stamped on them (Manufacture, and recertification). The manufacture date is an important factor when considering exchanging versus refilling. Take mine for example. It's only eight years old, which is fine, but I will want to exchange it when it's empty because it's a mess, and has been repainted a few times. It also has a couple of rust spots (only cosmetic).

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## 3 Discussions

Most US U-Haul locations have propane filling stations it's usually about \$10 for a tank in my recollection they charge based on weight added. I smoke with wood more often.

Yes, you covered all that pretty well. You do know that ten years is the limit on the first tank certification date. However, it can be recertified for an addition ten years (you may want to check that time limit, I could have the length wrong) but with that stated, you can still use your tank even after the FIRST date. We have a local hardware store that fills tanks, but does it the fair right way. They only charge for what you refilled to. In other words, if your tank is 1/4 full, you can have it filled to the top (sore a speak) for 75% of a total refill cost.

1 reply

It may vary by state, or country. I was always under the impression that the first cert was 12 years, and re-certs are only good for additional 4, or 5 years. I wasn't sure, that's why I didn't specify.
There are lots of reasons it's good to know about your tank, and knowing is half the battle when it comes to not getting ripped off. Thanks for your comment.