The length of time an RV heater will last on propane depends on several factors, including the size of the propane tank, the number of appliances relying on propane usage, how often those appliances are used, and how much energy the RV appliances consume while operating. Understanding the technical specifications and performing DIY calculations can help RV owners estimate their propane usage and manage their heating costs effectively.
Technical Specifications
- Propane Density: Propane weighs approximately 4.25 pounds per gallon.
- Propane Energy Content: One gallon of propane contains approximately 91,500 BTUs (British Thermal Units), which is a standard way of measuring and comparing energy consumption and fuels in the United States.
- RV Furnace Sizes: Smaller RV furnaces typically have a rating of 35,000 BTUs, while larger RV furnaces can be rated up to 40,000 BTUs.
Factors Affecting Propane Consumption
- Propane Tank Size: The size of the propane tank in an RV can vary, with common sizes ranging from 10 to 30 pounds (or 4.7 to 14 gallons).
- Number of Appliances: RVs often have multiple propane-powered appliances, such as the furnace, water heater, stove, and refrigerator, which can all contribute to propane consumption.
- Appliance Usage: The frequency and duration of use for each propane-powered appliance can significantly impact the overall propane consumption.
- Climate and Temperature: The outdoor temperature and the desired indoor temperature can affect the runtime and energy consumption of the RV’s furnace, which is typically the largest propane-powered appliance.
DIY Propane Consumption Calculation
To estimate the runtime of an RV heater on a given propane tank, you can use the following step-by-step DIY calculation:
- Determine the size of the propane tank in gallons:
- Divide the tank size in pounds by 4.25 to get the total gallons.
- For example, a 30-pound propane tank would contain approximately 7 gallons (30 ÷ 4.25 = 7).
- Calculate the total BTUs available in the propane tank:
- Multiply the total gallons by 91,500 BTUs per gallon.
- For a 7-gallon tank, the total BTUs would be 640,500 (7 × 91,500 = 640,500).
- Determine the BTU rating of the RV’s furnace:
- Smaller RV furnaces are typically rated at 35,000 BTUs.
- Larger RV furnaces can be rated up to 40,000 BTUs.
- Calculate the total continuous runtime of the RV heater:
- Divide the total BTUs in the tank by the BTU rating of the furnace.
- For a 7-gallon tank (640,500 BTUs) and a 35,000 BTU furnace, the runtime would be approximately 18.3 hours (640,500 ÷ 35,000 = 18.3).
Real-World Examples
- Stationary RV Owner: A full-time stationary RV owner reported that a 7-gallon propane tank can last 7-10 days in a typical 20-30°F winter, with the nighttime thermostat set to 60°F.
- Frequent RV Traveler: Another RV owner mentioned that a 30-pound propane cylinder (approximately 7 gallons) typically lasts 5 weeks, considering it is used for the stove/oven, fridge, and water heater.
Strategies to Conserve Propane
- Monitor Propane Levels: Use a propane tank gauge to keep track of the fuel level and prevent running out of propane unexpectedly.
- Reduce Appliance Usage: Turn off the hot water heater when not in use and consider using electric blankets or other heating sources to reduce propane consumption.
- Improve Insulation: Enhance the RV’s insulation to minimize heat loss and reduce the runtime of the furnace.
Conclusion
The length of time an RV heater will last on propane can vary significantly based on the technical specifications of the RV, the number and usage of propane-powered appliances, and the climate conditions. By understanding the factors that influence propane consumption and performing DIY calculations, RV owners can better manage their propane usage and costs, ensuring their heating needs are met throughout their travels.