how-to-know-how-full-or-empty-your-propane-tank-is

Nearly everyone has the typical 20-pound (5-gallon) barbecue grill propane tank.

A common question:
How do you accurately know how empty or full your propane tank really is?

One quick and easy way to know:
BBQ grill propane tank gauge specifically calibrated for 20-pound (5-gallon)

PROPANE TANK GAUGE SCALE
propane tank scale for bbq grill

 
Alternatively you could measure your own portable tank or other size tanks (e.g. a 30 pound RV propane tank).

Here’s the best and most accurate way to find out how much propane is left in your tank:

(UPDATED)

 

Weigh The Propane Tank

You might use this multipurpose luggage scale:

LUGGAGE SCALE
Luggage scale up to 110 pounds

 
All propane tanks have 2 weights stamped onto the top handle (the collar).

– One represents the tank’s empty weight (Tare Weight)

– The other represents its full weight (full with water… see below)

propane-tank-tare-weight-tc-wc

TW (T.W. Tare Weight)

This is the weight of the tank itself when empty.

WC (W.C. Water Capacity)

This is the weight of the water required to fill the tank (yes, water).

 
The typical 20-pound (5-gallon) barbecue grill tank will hold 47.6 pounds of water.

Regulations limit the propane level to not exceed 42% of the water capacity of the tank.

Long story short – The safe maximum weight of propane in a typical barbecue grill tank is 20 pounds (42% of 47.6 = 20 pounds).

 

Subtract Tare Weight From Measured Weight

So, what do we do with this information regarding a propane tank’s ‘Tare’ weight?

How do you actually discover how empty or full your propane tank is?

Simply weigh your propane tank and subtract it’s tare weight!

h-110-hanging-scale

For example, I just weighed my bbq grill tank and it weighs 32.6 pounds. The tare weight stamped on the collar is 16.6 pounds.

32.6 – 16.6 = 16 pounds of propane

20 pounds is considered maximum regulation full.
In my example, 16 pounds is 4/5 full, or 80%.

80% is now considered full due to safety reasons.

Note: Refill stations will only fill a 20 lb propane tank to 80% of it’s maximum. Here’s more about it and why they do that: How many gallons of propane in a 20 lb tank

 
You can use any scale. A floor scale, or a hanging scale.

There are several hanging scales on the market. I’ve been using the one picture above for my 20 & 30 pound portable propane tanks (bbq and RV):

American Weigh Scale

 
Tip! Depending on the weather conditions you may actually see condensation on the sides of a propane tank. There will be a clear demarcation indicating the level of propane inside the tank!

 
Here’s a chart where you can check the stamped W.C. on your propane tank and cross reference the maximum pounds of propane that will fill it.

Propane Cylinder (Tank) Filling Chart

W.C. — Pounds Propane

2.39 — 1
4.78 — 2
7.17 — 3
9.56 — 4
11.9 — 5
14.3 — 6
16.7 — 7
19.1 — 8
21.5 — 9
23.9 — 10
26.2 — 11
28.6 — 12
31.0 — 13
33.4 — 14
35.8 — 15
38.2 — 16
40.6 — 17
43.0 — 18
45.4 — 19
47.8 — 20
59.7 — 25
71.7 — 30
78.8 — 33
83.6 — 35
95.6 — 40
105.1 — 44
119.5 — 50
239.0 — 100