How Much Propane Does a Modine Heater Use? A Comprehensive Guide

The Modine heater is a popular choice for heating garages, workshops, and other commercial or residential spaces, and it can run on either propane or natural gas. Understanding the propane consumption of a Modine heater is crucial for ensuring efficient and cost-effective heating. In this comprehensive guide, we’ll dive deep into the factors that influence the propane usage of a Modine heater and provide you with the necessary information to make an informed decision.

Factors Affecting Modine Heater Propane Consumption

The amount of propane a Modine heater consumes can vary significantly based on several key factors:

  1. Heater Size: Modine heaters come in a range of BTU (British Thermal Unit) capacities, from 30,000 BTU to 200,000 BTU. Larger heaters will naturally consume more propane per hour than smaller models.

  2. Ambient Temperature: The colder the outdoor temperature, the more propane a Modine heater will consume to maintain the desired indoor temperature. This is due to the increased heat loss through the building’s envelope.

  3. Runtime Duration: The longer the Modine heater runs, the more propane it will consume. Factors like insulation, building size, and thermostat settings can all impact the runtime.

  4. Heater Efficiency: Modine heaters have varying levels of efficiency, which can affect their propane consumption. More efficient models will use less propane to generate the same amount of heat.

Typical Modine Heater Propane Consumption

how much propane does a modine heater use

According to the information provided, a typical Modine heater for a two-car garage uses approximately 100,000 BTU per hour. Given that a gallon of propane contains 91,502 BTUs of heat energy, a Modine heater of this size would use approximately 1.09 gallons of propane per hour.

However, it’s important to note that this is just an estimate, and the actual propane consumption may vary depending on the factors mentioned above. To provide a more comprehensive understanding, let’s look at some real-world examples:

Example 1: Heating a 936 Square Foot Outbuilding

A user on the Winnipesaukee Forum reported using a Modine heater to heat a 936 square foot outbuilding with R-19 walls and R-30 ceiling insulation. In 2019, they used 1,000 gallons of propane to heat the building, which suggests an average usage rate of approximately 2.74 gallons per day.

Example 2: Powering a Modine Heater with a 100# Propane Tank

Another user on the Sawmill Creek Woodworking Community reported using a 100# propane tank to fuel their Modine heater. Based on the fact that propane weighs 4.24 pounds per gallon, this tank would hold approximately 23.6 gallons of propane. A gallon of propane yields 91,500 BTUs, so this amount of propane would provide approximately 2,165,400 BTUs of heat energy.

Selecting the Right Propane Tank Size for a Modine Heater

When it comes to choosing the right size propane tank for a Modine heater, the Garage Journal forum recommends a 120-gallon tank, which will hold 100 gallons at 80% capacity. This should be sufficient for most residential garages and workshops, even in colder temperatures.

It’s important to note that the actual propane consumption may vary based on the factors mentioned earlier, and it’s always a good idea to consult with a professional or refer to the manufacturer’s recommendations to ensure you select the appropriate tank size for your specific needs.


The amount of propane a Modine heater uses can vary significantly based on factors such as the heater size, ambient temperature, runtime duration, and heater efficiency. By understanding these factors and the real-world examples provided, you can make an informed decision about the propane consumption of your Modine heater and select the appropriate propane tank size to meet your heating needs.

Sawmill Creek Woodworking Community Thread
Winnipesaukee Forum Thread
Garage Journal Forum Thread
Modine HVAC Product Information
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