No one in an RV, whether vacationing or long term living, wants to turn on a cold shower, try to light a stove/oven burner and see nothing, or turn on a furnace and feel no heat. You filled the tanks, but now they’re empty- and it’s only been a couple of weeks.
No, there’s no gremlin or “propane eating ghost.” True, if you don’t have propane covers on your tanks, some unscrupulous person could turn the valves off, or disengage your hoses from your tanks. That’s pretty rare. You could also have a leak somewhere in your system.
The other possibility is, you didn’t calculate how much propane you really needed, and that “half-of-one-tank” wasn’t enough to get you through until payday.
This article discusses how to calculate propane usage so you’re better able to assess how much you may need, how to detect leaks, and general propane safety.
RV’ing should be fun, not dangerous. For this article, the term RV refers to any type of recreational vehicle used as a temporary or long- term living space.
Calculating Propane Usage/Need
There are a few steps to this process. Keep in mind that this gives you a rough estimate, not precise measurements. It’s impossible to calculate that tomorrow, you may want a longer shower, bake break or a turkey instead of heat a can of chili, and so on.
First- A propane tank is considered full at 80% capacity. This allows for expansion of the gas inside the tank, especially in hot weather.
Second- The next time your propane tank is running on empty, take it in and have it filled. Don’t just trade it in for a “full” one. Take a notebook with you. Ask the attendant how much (gallons and/or pounds) your tank holds. Different size tanks hold different amounts. Write this figure down.
Third- Next, you’re going to find out your tank’s capacity in BTU’s- British Thermal Units, or heat units. Get the pounds/gallons you wrote down. If you have two tanks, add the two figures together. This is your total propane capacity.
BTU’s per pound = 21,548
BTU’s per gallon = 91,502
Fourth- Get your calculator and your notebook. Go to each of your propane appliances and find the BTU demand of each, and record it. It should be on each appliance- if not, the figure should be in the owner’s manual. If you don’t have the manual(s), try to search online by the product name.
Add up all the figures. This is the total propane demand.
Divide the total propane capacity by the total propane demand. This is approximately how long your tank(s) will last.
For example: Say I have two 17- gallon propane tanks for my RV. I don’t like to run out. They’re both full at a total of 32 gallons. (I’m using approximates to eliminate decimals right now.)
32 x 91,502 = 2,928,064 This is my total propane capacity.
My propane appliances add up to 42,900. This is my propane demand.
2,928,064 / 42,900 = 68.25(rounded). So I have roughly 68.25 hours of propane use in good weather.
In temperatures below zero, the capacity will be reduced by half or more. The gas contracts, and in temperatures of 40 and below, it’s a little hard for propane to burn.
Electric space heaters and cooking implements- crock pot, microwave, electric skillet, etc. are a good idea for cold climates.
You can also use this formula for the backyard propane barbeque or your propane standby emergency household generator.
Finding Propane Leaks/ Propane Safety
- If you smell rotton eggs, you have a propane leak. Propane itself doesn’t have an odor, so chemicals are added to get your attention.
- If you have or suspect a leak, DO NOT turn on anything electric. A spark could ignite the gas.
- Go outside and turn the valves to the tank(s) off.
- Open the windows and the door to allow the RV to air out.
- Turn on a gas burner on the stove and let the line bleed out.
- If you don’t want to work on a gas line, call an RV repairman immediately.
- If you want to find the leak and are confidant about your abilities, turn on one burner at a time on low with the tank(s) outside on.
- Begin at the outside tank and spray the tank valve(s) with soapy water. Watch for bubbling. If you see bubbling anywhere on the line(s), or at a coupling, you have a leak.
- DO NOT use the propane until the coupling or line has been repaired.
- Check the entire system before turning it back on.
- Install a carbon monoxide detector in your RV. Pay attention if it goes off.
- If your RV stays mostly in storage, test the detector every time you use it. If you live in it, or it stays in use, replace the batteries once a year like a smoke detector.
- If it goes off at a campground, and you’re sure you don’t have a leak, check to see if someone nearby is running a generator. Your trailer could be filling with their exhaust.
- If you have covers for your tanks, keep them on. It’s best to shade propane tanks in hot weather to reduce the expansion of the gas. It also hides the tanks from those who might have “sticky” on their fingers.
When properly managed, propane is a safe and easy to use, economical gas.
Oh, boy. I’m starting to sound like TV’s Hank Hill on “King of the Hill,” I tell you what.
Source: Mark Polk, “RV Educated? Calculating Propane Usage,” RV Education 101 website, no date given
