Tuesday, October 23, 2012

Measuring Propane Use

Ever wonder how to check propane level in your tank?  After using the propane this season for 5 trips now, cooking and using the heater occasionally, and then using the heater nearly all night this past trip as the temps dipped below freezing got me thinking, how much propane did I use?


First, you need to have some sort of scale that you can place your tank onto or suspend from.  I think the grocery stores would frown upon you taking the tank inside!

On the tank someplace you will find some valuable information stamped into it.  This is more commonly found around the tank handle since it would not damage or impact the tank.  Sometimes it may also be placed on a placard attached to the tank.  Here you will find the water weight capacity (W.C.) the tank is able to hold, which converts to a propane weight using a common ratio of these liquid densities.  You will also find the Tare Weight, or empty weight of your tank.

Propane Conversion Chart

In my case, I see on my tank that my W.C. is 47.6 lbs.  Going to the chart, I see that 47.6 is nearly equal to 20 lbs of propane.  I also find on my tank that the empty weight is 19.0 lbs.

Water Weight - Top, and Tank Empty Weight TW, Bottom
Given this information, my full propane tank will weigh in at 39 lbs when full.  To determine how much propane I have remaining in the tank, I just used a digital fish scale that I could lift the tank up off the ground with and get a reading.  Prior to our camping trip to Quakerwoods, I measured our tank to be 37 lbs.  This meant that in our prior 4 trips, when we predominately used the stove and grill for cooking quick meals, we used approximately 2 lbs of propane. 

Weighing the tank with a digital fish scale

Close up of the scale

Following our trip this past time and really running the furnace, I could definitely tell that the tank was lighter, and here in the photos you can see that it measured approximately 31.6 lbs!  That's 5.4 lbs of propane used in just one trip!  The heater worked great, but wow, did it suck some propane!

Now, 31.6 lbs is the total weight currently, so subtracting the 19 lbs of the tank weight I still have 12.6 lbs of propane remaining, enough for our last trip out this coming weekend, even if it gets really cold (which it currently is not forecast too, looks like mid 40*'s for the lows at night).

So, armed with this information, I can now check my tank periodically and get an estimate of the propane left in my tank.

Bonus Note: 1 lb of Propane can yield approximately 21,600 BTUs!  So, if you are trying to figure how much you can run that furnace or particular appliance in the camper, take it's rated BTU output/hour and divide by 21,600 BTUs, and you'll have how many pounds you can expect to use per hour.

Happy Camping!!

2 comments:

  1. Good info! Kind of hard to weigh the propane tank mounted in the motor home but.....We are going to purchase an "extended stay" hook up that will allow a propane tank to feed the system. We have used the furnace sparingly, instead we use an electric fireplace for the main coach area and a portable ceramic heater for the bedroom area, it saves propane $ and works very well.

    Our main draw on the propane is for hot water and we limit the use so it’s not reheating all day when we are out. When we want to do dishes or shower we turn on the pilot switch on the wall mounted panel and in a few minutes it’s good to go. We would like to replace our Atwood 6 gallon water heater with an updated electric/gas unit.

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  2. Essae is the India’s leading manufacturer and supplier of Tank Weighing Scale . Offering our customers inventive and cost effective solutions for almost every kind of industrial weighing application, Whether your needs are for just a single load cell or a complete batching system you can have confidence in our products, which will be based on thousands of successful installations over the last 20 years.

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