The short answer to whether you can convert a propane fire table to natural gas is yes, it is usually possible, but it is rarely a simple plug-and-play solution. While both fuels are popular for outdoor heating, they operate at significantly different pressures, which necessitates specific components to ensure safe and efficient operation. Understanding the technical and safety implications of such a conversion is critical before deciding to proceed, as it involves more than simply swapping out a hose.
Understanding the Core Differences: Propane vs. Natural Gas
The primary reason a conversion requires careful planning lies in the fundamental properties of the two fuels. Propane is stored in a liquid state under high pressure within a portable tank, while natural gas is delivered as a vapor through low-pressure utility lines. Specifically, propane appliances operate at approximately 11 inches of water column (WC), whereas natural gas appliances are designed for roughly 3.5 inches WC. This pressure discrepancy means that without the correct components, a direct swap could result in a dangerously vigorous flame or a burner that fails to ignite altogether.
The Role of the Orifice and Regulator
The orifice is the small brass valve that meters the flow of gas to the burner. Because propane requires higher pressure to vaporize correctly, its orifice hole is drilled much smaller than the one designed for natural gas. Installing a natural gas orifice into a propane fire table would allow too much gas to flow, creating an unsafe condition. Conversely, trying to run propane through a natural gas orifice would starve the burners of fuel. Therefore, a conversion kit must include a new orifice sized appropriately for natural gas pressure to ensure a clean and controlled burn.
Assessing Your Fire Table for Conversion
Not all fire tables are suitable for conversion, and attempting to do so without the proper design features can be frustrating or hazardous. You should first look for a conversion kit specifically manufactured by the same brand as your fire table, as these are engineered to meet the exact tolerances and safety standards of that model. If a manufacturer-specific kit is unavailable, you will need a universal kit, but this requires a bit more technical know-how to ensure compatibility with your burner setup and venting configuration.
Venting Considerations
One of the most overlooked aspects of a gas conversion is the venting system. Propane fires are often designed as "vent-free" or "ventless," allowing them to operate efficiently without a chimney because the vapor burns cleanly. Natural gas, however, typically requires a dedicated vent to the exterior to manage condensation and ensure proper air intake. If your table was originally designed to run on propane and lacks a provision for a vertical vent pipe, you may need to install one or reconsider the conversion altogether to avoid indoor air quality issues.
The Conversion Process and Safety
Assuming you have the correct orifice and compatible venting, the physical conversion involves shutting off the gas supply, removing the old burner components, and installing the new hardware. While this might sound straightforward, it is crucial to turn off the gas at the source and allow the system to cool completely before beginning. Any mistake in reassembly, such as cross-threading a line or failing to check for leaks, can lead to gas accumulation and create a serious fire or health hazard.
Testing for Leaks
Once the conversion is mechanically complete, a thorough leak test is non-negotiable. You should never attempt to ignite the fire table without first ensuring the system is sealed. The safest method involves applying a solution of soap and water to all connections and slowly introducing gas; if bubbles form, you have a leak that must be addressed immediately. Only when no leaks are detected and the flame burns evenly blue should you consider the project successful.
Weighing the Pros and Cons
Converting a propane fire table to natural gas can offer significant long-term convenience, particularly if you already have a natural gas line in your outdoor living space. This eliminates the need to schedule propane tank refills or manage heavy cylinders on your patio. However, you must factor in the cost of the conversion kit, any necessary venting modifications, and potentially professional installation fees to determine if the project is truly worthwhile compared to purchasing a dedicated natural gas unit outright.
