How to Estimate Fuel Left in Propane Tank
- 1). Check the propane tank for the tare weight number. This number is usually marked with TW and stamped onto the collar near the valve, and it indicates how much the tank weighs when it's empty. Put the tank on a scale and check how much heavier it is than the TW number. The extra weight is propane.
- 2). Use a magnetic strip thermometer. This type of thermometer does not show the exact temperature, but indicates temperature differences within the cylinder by turning different colors along a strip. The part of the cylinder holding propane will be a different temperature than the empty part of the cylinder.
- 3). Pour hot water down one side of the tank. The empty part of the cylinder will become warm, while the part holding propane will stay cooler. You can feel the difference when you put your hand on the tank. If the weather is warm and humid, you may even see some condensation on the side of the tank where the propane is located.
- 4). Pick up the cylinder and swing it a little bit from side to side. Then hold the tank still, and you'll be able to hear the gas slosh and feel the weight shift from side to side. This should at least give you a rough idea if there's enough propane in the tank to cook dinner tonight.
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