Converting Your Home Appliances From Propane to Natural Gas

Key Differences Between Propane and Natural Gas

Propane and natural gas are both clean-burning fossil fuels, but their physical characteristics require different equipment configurations.

• Operating Pressure: Liquid propane operates at a higher system pressure (approx. 11 inches of water column) compared to residential natural gas (approx. 7 inches of water column).

• Energy Density: Propane packs more energy per unit volume, producing roughly 2,516 BTUs per cubic foot compared to natural gas’s 1,030 BTUs per cubic foot.

• Gas Density: Propane is heavier than air and settles in low spots if it leaks. Natural gas is lighter than air and dissipates upward into the atmosphere.

PROPANE (LP):
• Higher Pressure (11" WC)
• Higher BTU Content (~2,516 BTU/cu. ft.)
• Smaller Burner Orifice Sizes
• Heavier than Air (Settles Low)

NATURAL GAS (NG):
• Lower Pressure (7" WC)
• Lower BTU Content (~1,030 BTU/cu. ft.)
• Larger Burner Orifice Sizes
• Lighter than Air (Rises and Dissipates)

Because natural gas contains less energy per cubic foot, appliances need to burn a larger volume of gas to produce the same heat output.

Essential Components of an Appliance Conversion

Converting a stove, clothes dryer, furnace, or water heater involves modifying several internal components. Never connect an unconverted propane appliance directly to a natural gas supply line.

   ┌────────────────────────────────────────────────────────────┐
   │            APPLIANCE CONVERSION COMPONENTS                 │
   ├────────────────────────────────────────────────────────────┤
   │ 1. Orifice Spuds   │ Swap to larger drill sizes            │
   │ 2. Regulators      │ Reframe or invert internal springs    │
   │ 3. Air Shutters    │ Re-adjust primary air intake gaps     │
   │ 4. Valves / Pilots │ Re-calibrate low-burn bypass screws   │
   └────────────────────────────────────────────────────────────┘

Qualified gas fitters replace small propane orifice spuds with larger natural gas orifices. This allows more gas volume to reach the burner. Technicians also invert or adjust the internal appliance pressure regulator spring to step down the incoming natural gas supply pressure correctly.

Finally, the installer sets the burner's primary air shutter. Proper adjustment ensures the correct balance of fuel and oxygen, producing clean blue flames without yellow tipping or excessive carbon monoxide production.

Upgrading Home Supply Piping for Natural Gas

Because natural gas requires higher fuel volume to match propane's heat output, your existing gas supply pipes may be too small.

PROPANE SUPPLY LINE:  [ 1/2" Pipe ] ──► (High Pressure / Low Volume) ──► High Heat Output
NATURAL GAS LINE:     [ 3/4" Pipe ] ──► (Low Pressure / High Volume)  ──► Equal Heat Output

If your home's main distribution line is undersized, converting multiple appliances to natural gas will create a bottleneck. Running your furnace, water heater, and stove simultaneously can drop fuel pressure across all three units. Professional technicians check your total household BTU load to determine if branch lines need to be upsized to 3/4-inch or 1-inch pipes before converting appliances.

Cost Benefits of Natural Gas Conversions

While initial conversion costs include new line installations, appliance kits, and professional labor, long-term savings make natural gas a smart investment.

Converting to natural gas eliminates recurring fuel tank delivery fees, tank rental contracts, and the risk of running out of fuel during peak winter cold snaps.

Frequently Asked Questions

Can All Propane Appliances Be Converted to Natural Gas?

Most modern gas furnaces, ranges, water heaters, and clothes dryers can be converted using manufacturer-certified conversion kits. However, some budget appliances or older fireplace inserts are manufactured for a single fuel type only. Check the rating plate on your appliance before planning a conversion.

Why Are My Burner Flames Yellow After a Fuel Conversion?

Yellow flames mean incomplete combustion caused by an incorrect fuel-to-air mixture or an improper orifice size. This issue produces high levels of carbon monoxide soot. Turn off the appliance and have a certified technician inspect the conversion.

Do I Need a Permit to Convert My Home From Propane to Natural Gas?

Yes. Modifying fuel supply lines, adding main utility hookups, and converting appliance fuel sources require mechanical permits and safety inspections from your local building department.