How Much Propane Does a Radiant Heater Use?

The amount of propane a radiant heater consumes can vary significantly depending on factors such as the size of the space being heated, the efficiency of the heater, and the desired temperature. To calculate the propane usage, you can rely on the fact that there are approximately 91,000 BTUs (British Thermal Units) in a gallon of propane.

Estimating Propane Consumption for Radiant Heaters

Calculating Propane Usage Based on BTU Rating

As a general rule, a 30,000 BTU radiant propane heater will use around 0.33 gallons of propane per hour when operating at full power. To determine the propane consumption for your specific heater, you can use the following formula:

Propane Consumption (gallons per hour) = Heater BTU Rating / 91,000 BTUs per gallon

For example, if you have a 50,000 BTU radiant heater, the estimated propane consumption would be:

Propane Consumption = 50,000 BTU / 91,000 BTU per gallon = 0.55 gallons per hour

Factors Affecting Propane Consumption

Several factors can influence the actual propane consumption of a radiant heater:

  1. Space Size: Larger spaces require more BTUs to maintain the desired temperature, leading to higher propane usage.
  2. Insulation and Ventilation: Well-insulated and sealed spaces will require less heating, reducing propane consumption. Poorly insulated or ventilated areas may result in higher propane usage.
  3. Desired Temperature: Higher target temperatures will increase the heating load and, consequently, the propane consumption.
  4. Heater Efficiency: More efficient radiant heaters will use less propane to achieve the same heating output.
  5. Ambient Temperature: Colder outdoor temperatures will increase the heating demand, leading to higher propane usage.

Determining Propane Tank Size for Radiant Heating

how much propane does a radiant heater use

The size of the propane tank required for a radiant heating system depends on the total heating load and the expected usage patterns.

Example: Garage Heating with Radiant Heater

In a scenario where a 48′ x 32′ x 12′ garage with 6 heating zones is equipped with a tankless propane water heater for heating, a 120-gallon propane tank may be sufficient to maintain a temperature range of 55°F to 60°F in Northern Ohio.

Larger Radiant Heating Systems

For larger radiant heating systems, such as a hydronic radiant floor system in a 4,000 square foot space, the propane consumption can be significantly higher. In one example, a system was using an average of 300 gallons of propane per month, with a combi boiler reducing the temperature drastically when trying to increase the flow rate.

Optimizing Propane Efficiency for Radiant Heating

To ensure efficient propane usage in a radiant heating system, it’s essential to:

  1. Properly Size the System: Ensure that the radiant heater and the overall heating system are correctly sized for the space being heated.
  2. Improve Insulation and Sealing: Enhance the insulation and air sealing of the space to reduce heat loss and minimize the heating load.
  3. Monitor Propane Consumption: Regularly monitor the propane usage and adjust the system settings or usage patterns accordingly.
  4. Maintain the System: Regularly service and maintain the radiant heater and the entire heating system to ensure optimal efficiency.


The amount of propane a radiant heater uses can vary significantly, but it’s possible to estimate the consumption based on the heater’s BTU rating and the size of the space being heated. By understanding the factors that influence propane usage and taking steps to optimize the system, you can ensure efficient and cost-effective heating with your radiant heater.


  1. Propane Tank Size for Radiant Floor Heat
  2. 30,000 BTU Vent-Free Radiant Propane Heater
  3. Hydronic Radiant Floor Propane Usage
  4. Propane Usage for Radiant Floor Heating
  5. BTU Calculator