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).