Can I Convert a Natural Gas Pool Heater to Propane?

Converting a natural gas pool heater to propane is a feasible option for many pool owners, but it requires careful consideration and attention to detail. This comprehensive guide will walk you through the process, providing technical specifications, safety considerations, and step-by-step instructions to ensure a successful conversion.

Compatibility and Preparation

Before embarking on the conversion process, it’s crucial to ensure that your pool heater is compatible with propane. Most pool heaters can be converted, but it’s essential to verify the model and BTU rating. You can find this information in your heater’s user manual or by contacting the manufacturer.

Once you’ve confirmed the compatibility, you’ll need to gather the necessary tools and materials, including:

  • Propane conversion kit (specific to your pool heater model)
  • Adjustable wrench
  • Screwdrivers (flat and Phillips head)
  • Leak detection solution or spray
  • Teflon tape

Orifice Replacement

can i convert a natural gas pool heater to propane

The primary step in converting a natural gas pool heater to propane is to replace the orifice. The orifice is a small opening that regulates the flow of gas to the burner. Propane has a higher energy content than natural gas, so the orifice size needs to be adjusted accordingly.

The typical orifice size for a natural gas pool heater with a 399,000 BTU rating is a #50 orifice. For a propane conversion, you’ll need to replace it with a smaller #40 orifice. This change is crucial to ensure the proper gas-to-air mixture and efficient combustion.

Gas Pressure Adjustment

In addition to the orifice change, you’ll need to adjust the gas pressure regulator on your pool heater to accommodate the higher pressure of propane. Propane typically operates at a higher pressure than natural gas, so the regulator will need to be set to the appropriate propane pressure, which is typically around 11 inches of water column (WC).

It’s important to use a manometer or other pressure-measuring device to ensure the gas pressure is adjusted correctly. Improper gas pressure can lead to safety issues and poor heater performance.

Venting Considerations

Propane burns differently than natural gas, which can affect the venting requirements of your pool heater. In some cases, you may need to adjust the venting system to ensure proper combustion and exhaust of the propane-fueled heater.

Consult the manufacturer’s instructions or a qualified HVAC technician to determine if any venting modifications are necessary. Proper venting is crucial for safe operation and to prevent the buildup of harmful gases.

Step-by-Step DIY Conversion

If you feel comfortable performing the conversion yourself, follow these steps:

  1. Turn off the Gas: Shut off the gas supply to your pool heater and allow it to cool completely before starting the conversion process.
  2. Remove the Burner Tray: Carefully remove the burner tray from the pool heater to access the orifice.
  3. Replace the Orifice: Unscrew the existing natural gas orifice and replace it with the propane orifice included in the conversion kit. Ensure the new orifice is tightened securely.
  4. Adjust the Gas Pressure Regulator: Use a manometer to measure the gas pressure and adjust the regulator to the appropriate propane pressure, typically around 11 inches WC.
  5. Reassemble the Pool Heater: Carefully reassemble the pool heater, making sure all components are properly secured and sealed.
  6. Perform a Leak Test: Apply a leak detection solution or spray to all gas connections to ensure there are no leaks.
  7. Test the Pool Heater: Turn on the gas supply and start the pool heater to ensure it’s functioning correctly and safely.

Safety Considerations

Converting a natural gas pool heater to propane is a task that requires caution and attention to detail. Improper conversion can lead to serious safety hazards, such as gas leaks, explosions, or carbon monoxide poisoning. If you’re not comfortable performing the conversion yourself, it’s highly recommended to hire a licensed and experienced HVAC technician to ensure the job is done correctly and safely.


Converting a natural gas pool heater to propane can be a cost-effective and practical solution for many pool owners. By following the guidelines outlined in this comprehensive guide, you can successfully complete the conversion process and enjoy the benefits of a propane-fueled pool heater. Remember to prioritize safety, consult the manufacturer’s instructions, and consider seeking professional assistance if you have any doubts or concerns.