A propane heater uses 2.6 gallons to 40 gallons of propane per day, if it runs all the time (most won’t).

A 30,000 BTU heater uses 7.9 gallons of propane per day, and an 80000 BTU furnace uses up to 21 gallons per day.

Propane heaters and furnaces are available in a wide variety of types and sizes. They can be used in tents, cabins, garages, patios, basements, and inside the home itself. This article will give you what you need to know about how much propane you can expect to use if you have one or more of these heating devices.

## How Much Propane Does a 30000 BTU Heater Use

One-third gallon, aka .33 gallons, per hour. If it ran all day, it would use up to 7.9 gallons.

How is this determined?

Heat from an open (non-ducted) propane heater comes directly from the open flame. So, for practical purposes, they are 100% efficient, meaning that all of the heat energy will be available in the space being heated. One gallon of propane will yield around 91,500 BTU per hour (91,500 BTU/h).

So, if we divide 30,000 BTU into 91,500 BTU, we get 3.05. That is how many hours one gallon of propane will last when used by a 30,000 BTU heater. This means that in just 1 hour, that same heater will use approximately 1/3 of a gallon of propane.

## How Much Propane Does an 80,000 BTU Furnace use?

It will burn .9 gallons per hour or about 21 gallons for every 24 hours it runs.

Furnaces that are ducted rather than blowing heated air directly out of the furnace into the space they heat are not as efficient because of the way they produce heat in a building.

For example, a forced air propane furnace burns the fuel inside the furnace which heats up a *heat exchanger*, then the gasses go out a vent or chimney. Air from the rooms is blown over the heat exchanger and is heated indirectly from the flames, not directly, as it is in a heater. This results in an *output* of between 80% and 99% of the *input* value of 80,000 BTU.

So, an 80,000 BTU furnace will use approximately .9 gallons per hour, or almost 21 gallons per day if it ran non-stop, but in a well-insulated home and if it is properly sized, it won’t run continuously.

And the higher efficiency the furnace, the more BTUs it will deliver into your living space.

- 80,000 x 80% = 64,000 BTU of heat for your living space.
- 80,000 x 90% = 72,000 BTU.
- 80,000 x 95% = 76,000 BTU.

### How Much Propane Does a Heater Use?

Furnace Size/BTUs | Per Hour | Per Day |

10,000 | .11 gallons | 2.62 gallons |

15,000 | .16 gallons | 3.94 gallons |

18,000 | .2 gallons | 4.72 gallons |

20,000 | .22 gallons | 5.25 gallons |

25,000 | .28 gallons | 6.56 gallons |

30,000 | .33 gallons | 7.87 gallons |

35,000 | .38 gallons | 9.2 gallons |

40,000 | .44 gallons | 10.5 gallons |

60,000 | .66 gallons | 15.75 gallons |

75,000 | .82 gallons | 19.68 gallons |

80,000 | .875 gallons | 21 gallons |

100,000 | 1.1 gallons | 26.2 gallons |

125,000 | 1.37 gallons | 32.8 gallons |

150,000 | 1.64 gallons | 39.36 gallons |

## How much propane does a 30000 BTU heater use?

328 gallons per hour, 7.87 gallons per day, or 236.19 gallons per month.

## How much propane does an 80000 BTU heater use?

**.**875 gallons per hour, 20.99 gallons per day, or 629.84 gallons per month.** **

## How much propane does a 10000 BTU heater use?

.109 gallons per hour, 2.62 gallons per day, or 78.73 gallons per month.** **

## Are Ventless Propane Heaters Safe?

Many people wonder if they are safe, since there is no outside vent for the combustion gasses. If a propane appliance is functioning properly, it will produce what is called an “ideal burn” while heating, and will present no danger of carbon monoxide poisoning.

Additionally, all but the very least expensive propane heaters intended for indoor use come with a safety feature called an oxygen depletion sensor, which will automatically turn the unit off if oxygen levels drop below a certain threshold.

**How Long Will a 20 Pound Tank Last?**

A 20 pound tank or bottle contains about 4.7 gallons of propane. It will run an 18,000 BTU heater like the Big Buddy from Mr. Heater, for 24 hours at full heat or about twice that long on the 9,000 BTU setting.

A 20 pound tank will keep one of the popular 30,000 BTU ventless heaters going for about 14 hours.

## What is the Advantage of a 2 Stage Furnace or Heater?

They have two heat levels. Low heating is either 65% or 70% of full capacity depending on the brand/model. High heat is, of course, 100%.

You’ll save energy cost with a 2 stage furnace because it will run on the lower capacity whenever it can make enough heat on low to satisfy the demands of the thermostat. In very cold weather, it will have to run at 100% more of the time to keep your home warm.