How to change over from liquid petroleum gas (LP or bottled gas) to natural (piped-in) gas for gas fired appliances in a building
Advice for changing from LP gas to Natural gas in a building
Advice for converting between Natural gas and LP gas in a building
LP gas and Natural Gas conversion procedures & safety warnings
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This article explains the procedure for converting from LP gas or "bottled gas" to natural gas or "piped in gas" at a building. General safety warning: improper installation and even improper inspection and testing methods involving natural or "LP" gas can involve
dangerous conditions and risk fire or explosion. If you smell gas you should leave the building immediately and should do so without doing anything that could create a spark such as operating a light switch or telephone.
Advice for Converting From Propane to Natural Gas or from Natural Gas to Propane
If you are not sure whether your building and its appliances are served by LP gas (bottled gas or liquid petroleum gas) or by natural gas (piped-in gas), see the descriptions of each of these types of heating fuel at GAS PIPING, VALVES, CONTROLS.
Natural gas and LP gas appliance compatibility
These two fuels are similar in that both are used to provide energy to home heating systems and other appliances but they have some different properties of weight, method of distribution, and chemistry. Most gas appliances are delivered already set up to use either natural gas or LP gas but not both.
Most gas appliances can be converted from one fuel to the other - what is involved may be simply changing gas metering orifices in the equipment (for example at the burners on a stove) or it may also be necessary to change or adjust a gas regulator located inside the appliance. Do not hook up an LP gas-ready appliance to a natural gas supply nor can you connect a natural-gas ready appliance to an LP gas supply without reviewing and acting on the manufacturer's instructions for converting the appliance from one fuel to the other.
Important Safety Warning: be sure that all gas-fired appliances in your building have been properly set up for the correct type of gas to be consumed.
Do not connect an appliance set up for propane to a natural gas supply, and do not connect an appliance set up for burning natural gas to a propane gas supply without first making the required gas pressure and/or gas metering orifice adjustments. Making either of this mistakes can lead to gas leaks, fire, explosion, or potentially fatal carbon monoxide poisoning.
Virtually every modern gas fired appliance installation manual contains instructions for setting up the appliance to burn the proper fuel: LP gas (liquid propane from a tank installed at the property) or natural gas (piped in gas provided from a local gas utility company).
The pressure provided by natural gas is different from propane - adjustments will be needed at every gas fired appliance in the home.
Usually this means either an adjustment made at each gas burner at a metering device or in some cases a part actually has to be changed (an orifice through which the gas passes). On some appliances there may be a local gas regulator that also needs to be adjusted.
Where a gas burner metering device needs to be set properly for Natural Gas pressure or for LP gas pressure, the adjustment may be as simple as using a screwdriver or tool to turn the orifice from one position to another at each burner, or a part may need to be actually swapped out or exchanged. Appliance installation instructions will include sketches of where these parts are found as well as directions for how to set the metering device or regulator for the proper fuel.
Where is natural gas or LP gas pressure regulated for a gas fired appliance:
For LP Gas: at an LP gas pressure regulator mounted on or at the LP gas tank, possibly at an intermediate or building gas pressure regulator if the LP tank is distant from the building, at an LP gas pressure regulator inside of or at the gas fired appliance itself, and for some appliances such as gas ranges and ovens, additional gas flow regulation is performed by a special orifice right at the gas burner.
On many gas fired appliances the only adjustment that is required is to change or turn/adjust the gas metering orifice at the appliance burner.
Critical safety warnings about changing between gas fuel types: LP to or from Natural Gas
The proper setup of gas burning appliances is very important since failure to set the appliance for the proper gas type can result in very dangerous, even fatal carbon monoxide production from improper combustion.
If your natural gas supplying company or plumber who is doing the hookup has not already offered to do so, ask them to go through the home identifying every gas-burning appliance, determine exactly what changes are needed, and make them before the appliances are again turned on with the new fuel supply.
Follow the appliance setup and gas fuel type adjustment instructions in the appliance installation manual provided by the manufacturer. If you cannot find the installation manual for your gas fired water heater, stove, furnace, boiler, or other gas fired appliance, make a note of the appliance name, model number, and serial number, and contact the manufacturer directly for these critical instructions.
The actual conversion from LP to or from Natural gas at the appliance itself is usually quite easy, but doing it properly is essential for safety.
These two gas fuels are similar in that both are used to provide energy to home heating systems and other appliances but they have some different properties of operating gas pressure, weight, method of distribution, and chemistry. Most gas appliances are delivered already set up to use either natural gas or LP gas but not both.
Most modern gas appliances can be converted from one fuel to the other - what is involved may be simply changing gas metering orifices in the equipment (for example at the burners on a stove) or it may also be necessary to change or adjust a gas regulator located inside the appliance.
However some older gas appliances such as the gas stove shown in our photo (above/left) may not be convertible between gas fuels.
Watch out: Do not hook up an LP gas-ready appliance to a natural gas supply nor can you connect a natural-gas ready appliance to an LP gas supply without reviewing and acting on the manufacturer's instructions for converting the appliance from one fuel to the other. It is virtually always the case that some equipment adjustments and changes are necessary to switch between natural gas and propane gas.
For example as JR, an industry manager familiar with gas pressures pointed out, these two fuel gases operate at different pressures. In residential appliances
Natural Gas system pressure: Natural gas operates at a nominal pressure of 7” WC (about 0.253 psi)
LPG or Liquid Propane Gas system pressure: LP gas or propane operates at a nominal pressure of 11” WC (about 0.397 psi)
Actual NG or LPG gas pressures vary: [Note: the exact pressure you see in the building at an appliance may vary from these numbers depending on the gas distribution piping system size, diameter, number of appliances served, number of appliances operating, regulator adjustment, and other factors. See Gas Regulators for Appliances and Gas Regulators for LP Tanks. See LP or Natural Gas Pressures for a table showing the range of variation
in LP gas pressure in the tank at various temperatures. - Ed.]
LP Gas <-> Natural Gas Appliance Conversion Steps - Example
The following examples show where adjustments are required on a typical gas stove to convert between LP gas and Natural Gas. These examples are for a Glenwood Sunray gas range produced by the Glenwood Range Company. These adjustments should be made by a trained appliance installer or service technician.
Our photo (left) shows gas appliance parts and controls for sale at an open air market held on Tuesdays in San Miguel de Allende, Mexico. But as we warn below, installing or modifying parts on a gas appliance can be dangerous if you don't know what you are doing.
Watch out: these gas fuel type conversion examples are intended only for the purpose of general understanding of the type of changes that may be needed at a gas fired appliance. Be sure to consult with the manufacturer or the installation and service manual to obtain and follow the exact gas fuel conversion steps for your particular gas appliance. Otherwise your gas appliance is likely to be unsafe. To obtain the proper installation and service manual for your gas appliance you will need the product name, model number, code numbers/letters, serial number, and the date of installation or manufacture. .
How to Adjust the Gas Pressure Regulator to Convert between LP Gas and Natural Gas - Example
Here is an example of a convertible gas range pressure regulator. [Click any of these images for a larger, more detailed version.]
Using simple tools the pressure regulator cap is removed, flipped over, and reinstalled.
Gas pressure regulators used in several home appliances may be similar, but as we warn above, be sure to find and obtain the precise instructions from the manufacturer of your own appliance brand, model, and serial number in order to be safe.
How to Adjust the Top Burners to Convert between LP Gas and Natural Gas - Example
Here is an example of a convertible gas range burner top.
The valve hood (at left in the photo) is adjusted to an open or closed position depending on use with natural gas or LP gas.
Find and obtain the precise instructions from the manufacturer of your own appliance brand, model, and serial number in order to be safe.
How to Adjust the Oven Burner & Thermostat to Convert between LP Gas and Natural Gas - Example
Here is an example of a convertible gas range pressure regulator.
The oven burner hood is adjusted to an open (Natural Gas) or closed (Propane) position depending on the fuel.
Find and obtain the precise instructions from the manufacturer of your own appliance brand, model, and serial number in order to be safe.
Additional steps may be needed for your appliance, such as adjusting air mixture at the burner for the proper flame.
Watch out: failing to properly install, adjust, and vent a gas fired appliance can result in dangerous, even fatal carbon monoxide poisoning, gas leaks, a fire, or other dangerous conditions.
What to Do if You Smell Gas Inside or Even Outside Near a Building
*** Immediate LP Gas or Natural Gas Safety Concerns:
Gas Odors: A gas leak can be indicated by gas odor such as in the utility area near appliances or elsewhere in the building.
From a safe location, call your gas company's
emergency line and/or your fire department. The text provided here is a working draft and may be incomplete or inaccurate. Contact us to suggest text changes and additions and, if you wish, to receive online listing and credit for that contribution.
Also see How to Report Defects in Oil Piping.
NOTICE: while example report language is provided here, reproduction of this or any of our web pages or their contents at other websites
or in printed documents for sale is prohibited.
You should have your plumber test, repair, or replace any suspect gas controls or piping promptly. Replacement of a control itself should not involve significant expense. This repair should not be deferred. You should be sure that building occupants know if this or other unsafe conditions are present.
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Additional technical contributors & reference sources for this article are listed below.
Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.
U.S. Energy Information Administration - eia.doe.gov/
U.S. Environmental Protection Agency - epa.gov/solar/energy-and-you/affect/natural-gas.html
At Natural Gas.Org www.naturalgas.org/environment/naturalgas.asp#emission you’ll find a table of combustion products
At geocities.com/rainforest/6847/report1.html is an interesting and detailed though not “neutral” report on the components and contaminants in the combustion of natural gas. You’ll see a long long list of emissions products, but look again – most of the contaminant levels listed are in the picograms.
apvgn.pt/documentacao/iangv_rep_part1.pdf lists the components in natural gas exhaust from vehicles
The Need Project, Manassas, VA: need.org/needpdf/infobook_activities/SecInfo/NGasS.pdf
Kroschwitz, Jacqueline I., and Mary Howe-Grant (eds.). "Gas, Natural." In Encyclopedia of Chemical Technology. 4th ed., vol. 12. New York: John Wiley and Sons, Inc., 1993.
Tussing, Arlon R., & Bob Tippee. The Natural Gas Industry: Evolution, Structure, and Economics. 2nd ed. Tulsa, OK: PennWell Publishing, 1995.
Thanks to reader E Leal for suggesting the addition of details about how to convert gas burning appliances from propane to natural gas or from natural gas to propane. 8/4/09
Thanks to reader JR for discussing LP and natural gas operating pressures and leak detection safety, October 2010.
Glenwood Range Company, Customer Service, 435 Park Ave., Delaware OH 43105, 614-363-1381, Glenwood-Sunray Service Center: 215-682-4211.
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