How Much Propane Does a Space Heater Use?

The amount of propane a space heater consumes can vary significantly depending on several factors, including the size of the heater, the BTU (British Thermal Unit) output, the efficiency of the unit, and the duration of use. Understanding the propane consumption of your space heater is crucial for managing your fuel supply, budgeting, and ensuring safe and efficient heating in your home.

Factors Affecting Propane Consumption in Space Heaters

Heater Size and BTU Output

The size of the space heater and its BTU output are the primary determinants of propane consumption. Larger heaters with higher BTU ratings will generally consume more propane than smaller, lower-output models. As a general rule, a 20,000 BTU space heater will use approximately 1.5 to 2 gallons of propane per hour, while a 30,000 BTU heater may consume 2 to 3 gallons per hour.

Heater Efficiency

The efficiency of the space heater also plays a significant role in its propane usage. More efficient models, often with features like electronic ignition and advanced combustion systems, can provide the same heating output while consuming less fuel. Typical propane space heater efficiencies range from 80% to 99%, with higher-efficiency models generally using less propane.

Duration of Use

The length of time the space heater is in operation directly impacts the amount of propane consumed. If the heater is used for extended periods, such as throughout the day or overnight, the propane usage will be higher than if it’s used for shorter, intermittent periods.

Environmental Factors

Factors such as ambient temperature, insulation, and air leaks in the home can also influence the propane consumption of a space heater. Colder outdoor temperatures and poorly insulated spaces may require the heater to work harder, leading to increased propane usage.

Calculating Propane Consumption for Space Heaters

how much propane does a space heater use

To estimate the propane consumption of your space heater, you can use the following formula:

Propane Consumption (gallons per hour) = BTU Output / Heater Efficiency / Propane BTU Content

– BTU Output is the rated output of the space heater in BTUs
– Heater Efficiency is the efficiency rating of the space heater, expressed as a decimal (e.g., 0.90 for 90% efficient)
– Propane BTU Content is the energy content of propane, which is approximately 91,500 BTU per gallon

For example, let’s say you have a 30,000 BTU space heater with an efficiency rating of 90%:

Propane Consumption = 30,000 BTU / 0.90 / 91,500 BTU per gallon
Propane Consumption = 0.37 gallons per hour

This means that your 30,000 BTU space heater with 90% efficiency will consume approximately 0.37 gallons of propane per hour of use.

Propane Consumption Estimates for Common Space Heater Sizes

To provide a more comprehensive overview, here’s a table with estimated propane consumption for various space heater sizes and efficiency levels:

Heater Size (BTU) Efficiency (%) Propane Consumption (gallons per hour)
15,000 80% 0.21
15,000 90% 0.18
20,000 80% 0.28
20,000 90% 0.24
25,000 80% 0.34
25,000 90% 0.30
30,000 80% 0.41
30,000 90% 0.37
35,000 80% 0.48
35,000 90% 0.43

Please note that these are approximate values, and actual consumption may vary based on the specific model, environmental conditions, and usage patterns.

Monitoring and Adjusting Propane Consumption

To effectively manage your propane usage and ensure the efficient operation of your space heater, consider the following tips:

  1. Monitor Propane Levels: Regularly check your propane tank levels to anticipate when a refill will be needed. This will help you avoid running out of fuel unexpectedly.

  2. Adjust Thermostat Settings: Lowering the thermostat setting on your space heater can significantly reduce propane consumption without sacrificing comfort.

  3. Insulate Your Home: Improving the insulation in your home can reduce the heating load, allowing your space heater to operate more efficiently and consume less propane.

  4. Maintain Your Heater: Regular maintenance, such as cleaning the burners and checking for any leaks or malfunctions, can help ensure your space heater is operating at its optimal efficiency.

  5. Consider Supplemental Heating: Using your space heater as a supplemental heat source, rather than the primary heating system, can help minimize propane consumption.

By understanding the factors that influence propane consumption and implementing these strategies, you can effectively manage your space heater’s propane usage and enjoy efficient and cost-effective heating in your home.


  1. BTU Calculator – Hot Propane
  2. How Much Propane Per Day? – Fall River Propane
  3. How Much Propane? – Advanced Propane