Propane tank size

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Feb 5, 2013
i own a 86 emc encore 25ft bought almost a year ago and been living in it off and on since. recently me and my gf decided to move in to it full time we are about a month or so into this life style except 1 problem we have run out of propane! this was the same propane that was in the rv when i purchased it almost a year ago in that time i never got the idea to find out WHAT SIZE is my propane tank? how many gallons does it hold? and i cant seem to find any info to answer that question on the internet so if anyone could please help me find the answer it would be greatly appreciated!
i will look for the label. i would prefer to know the capacity BEFORE i fill it so i can budget for a full tank. thanks for the advice.
A propane tank like you would use for a gas grill is what is called a 20lb cylinder. They do not hold 20 gallons. They hold about 4.2 to 4.5 gallons of propane. Do you have one tank or two? My tt has 2 20lb cylinders. Most have 30 pounders that should hold 6.5 gallons or so. Sounds like you guys use very little propane as I go through 1 tank for a weekend just cooking and bathing and nightly heat if needed.
we dont own a tt its a motorhome the tank is attached to the rig permanently. we use the propane mainly for hot water we cook with electric. thanks!
Without knowing specifically, your propane tank is probably somewhere between 20 - 40 gallons and should only be filled to 80% (16-32 gal).
The tank capacity in gallons should be embossed right into the side of the tank near the valves, per federal law and fire safety codes. That will be the gallonage for a 100% full tank (referred to as water capacity). You can only fill 80% with propane - have to leave room for the gas and expansion in warm weather.
I'm guessing it is a fixed tank built to ASME specs since it's in a motorhome, but a few motorhomes use the DOT-spec portable bottles.

This web page shows a typical ASME tank and its data plate.
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