How To Seal Propane Fittings

Propane is a gas that’s typically compressed and stored as a liquid. It’s sold in different sized tanks for a variety of uses. The gas is nontoxic, colorless, and virtually odorless. However an identifying odor is added to propane which leaks easier to detect. Propane is most commonly used for cooking, heating and as fuel for engine applications such as forklifts. When propane is used as vehicle fuel, it’s known as propane autogas. No matter what the application, propane gas must be safely transferred from the tank to the appliance using it by hoses and compression fittings. Threaded propane fittings are sealed with yellow PTFE (Teflon) gas-rated thread tape. Compression fitting seal themselves when used properly and do not require tape.

PTFE yellow gas line thread seal tape is designed and manufactured for natural gas, propane, butane, oil and chemical lines. Whenever a gas fitting is threaded it’s sealed with yellow gas-rated Teflon tape.

Propane is an explosive gas. Compression fittings are used to connect lines that transfer gas from a storage tank to an appliance where it will then be burned as fuel. Poor seals can allow gas to leak which can be dangerous. A tight seal on all fittings is essential to ensure that gas does not escape through the cracks.

Make sure your tank, fittings and hoses do not leak before using propane gas.

What Color Teflon Tape For Propane Fittings?

The only type of Teflon tape you can use on propane fittings is PTFE (Teflon) yellow gas line thread tape. PTFE yellow gas line thread seal tape is designed and manufactured for natural gas, propane, butane, oil and chemical lines. It’s the only color Teflon tape you can use to seal a threaded propane line.

Teflon tape comes in a variety of colors. The color of the tape dictates what type of line you can use it on. PTFE white and pink Teflon tape is for water lines. PTFE green Teflon tape is for oxygen lines. You should never use PTFE white, pink or green Teflon tape on a propane line because it may break down, deteriorate and cause gas leaks.

PTFE stands for PolyTetraFluoroEthylene which is another name for Teflon. When you shop for plumbers tape, it will be marketed as either Teflon tape or PTFE tape. It doesn’t make any difference which you buy because PTFE tape and Teflon tape are the exact same product.

The two most common colors/types of Teflon tape used are white and yellow. White is for water lines while yellow is for gas pipe.

Yellow: Use yellow Teflon gas line tape on things like a gas grill, dryer, stove or propane tank. Yellow tape is designed to seal threaded metal gas pipe which helps prevent gas leaks. It’s thicker than white tape and heat resistant.
White: Use white Teflon tape to seal water pipes, dishwashers and refrigerators. White tape is thinner and designed to stop water leaks. But it’s not very heat resistant and breaks down easily when used on a gas pipe.
Pink: A heavy duty version of white Teflon tape that can be used on water lines instead of white.
Green: Used on oxygen lines.

Step 1 Apply Yellow Teflon Tape

Wrap yellow gas-rated Teflon tape around the threads of the fitting. Wrap 2-3 layers of tape in the same direction as you’ll be twisting on the fitting. The tape should turn with the fitting, not unwrap itself when you twist.

Do not apply yellow tape on the compression end of the fitting. Compression fittings seal themselves when used properly. Yellow tape is only for use if you have a threaded connector.

Step 2 Connect The Hose

Insert the connection at the end of the hose onto the compression fitting and twist until it’s hand tight. Continue twisting the hose end with a wrench until it’s tight. Do not over-tighten or you could damage the fitting or hose.

If your tank requires an O-ring or similar connection, tighten the O-ring first, then attach the propane tank fitting over the top.

Step 3 Check For Gas Leaks

Make sure the propane gas is turned off by twisting the shutoff valve to the off position. Fill a small spray bottle with warm water and some dish soap. Turn the shutoff valve to open. Spray soapy water on the connection. If you see bubbles it means there’s a gas leak. Turn the shutoff valve to off and tighten the connection. Turn the valve on and re-rest the connection. If you see bubbles again, replace the compression fitting and hose.

Once you’ve replaced the fitting and hose, re-rest the connection with more soapy water.

Do Propane Fittings Need Sealants?

Yes, the threaded end of a propane fitting should be sealed with yellow PTFE (Teflon) gas-rated thread tape, a.k.a. plumbers tape. However the compression end of the fitting does not require tape or any other sealant. When used properly, compression fittings seal themselves with contact and pressure.