Which of the following is NOT a step in flare fitting installation?

Which of the following is NOT a step in flare fitting installation?

• A. Inspect the tubing to make sure it is squarely cut and free of damage and debris, such as burrs or paint.
• B. Slide the nut on the tube end with the threads facing outward.
• C. Flare the end with the flaring tool.
• D. Use a soldering iron to seal the flare.

Answer: (D)

In flare fitting installation, the seal is made by forming a precise flare on the tube end and tightening the nut so the flare cone mates securely with the flare seat. The tubing must be cut square and free of damage or burrs so the flare can form cleanly without gaps. The nut needs to be slid onto the tube first, with its threads facing outward, so it can engage the flare body when assembled. Finally, you create the flare with a flaring tool to the correct angle and smooth surface so the seal sits evenly and won’t leak. Using a soldering iron to seal the flare isn’t part of this process. Soldering is used for sweat joints on plain copper piping, but it does not belong in flare installation and can damage the flare surface or compromise the seal.

In flare fitting installation, the seal is made by forming a precise flare on the tube end and tightening the nut so the flare cone mates securely with the flare seat. The tubing must be cut square and free of damage or burrs so the flare can form cleanly without gaps. The nut needs to be slid onto the tube first, with its threads facing outward, so it can engage the flare body when assembled. Finally, you create the flare with a flaring tool to the correct angle and smooth surface so the seal sits evenly and won’t leak.

Using a soldering iron to seal the flare isn’t part of this process. Soldering is used for sweat joints on plain copper piping, but it does not belong in flare installation and can damage the flare surface or compromise the seal.