What type of solder is recommended when installing a copper elbow on an LP gas line?

When installing a copper elbow on an LP gas line, using 15% silver solder is recommended because it provides superior strength and durability in copper joints, particularly under the stress and potential vibration inherent in gas lines. Silver solder has a higher melting point and creates a stronger bond compared to other types of solder. This is critical in gas applications, where leaks can be hazardous, so a robust joint is essential to ensure safety and reliability.

Additionally, silver solder is less prone to corrosion and can withstand extreme temperature fluctuations, making it suitable for gas line applications. Its properties ensure that the joints remain secure and leak-free over time. This is particularly important in the context of LP gas lines, which require high standards of safety and reliability due to the flammable nature of the gas being transported.