Brazing Rods

[preetnep]

Do we use just silfos for cu to cu brazing or it could be 5 % silver brazing rod

[Admin]

From the B52 Mechanical Refrigeration Code,

Brazed joint — a gas-tight joint obtained by joining metal parts with alloys that melt at temperatures higher than 427 ºC (800ºF) but lower than the melting temperatures of the joined parts.

5.7.2.4 - The joints on copper tubing used in refrigeration systems shall be brazed. Soldered joints shall not be used in such refrigeration systems.

Visit the Silfos Q&A page here,
http://www.silfos.com/htmdocs/product_support/faq.html#Whatalloyisrecommendedforbrazingcoppertocopperjoints

Visit the Silfos Alloy Selection guide here,
http://www.silfos.com/htmdocs/product_support/alloy_selection_guide.html

The Refrigeration and Air Conditioning Technology 6th Edition says you want to use an alloy with 15% silver to braze copper to copper, or 45% silver to braze dissimilar metals.

The Lennox XC16 manual says,

Use silver alloy brazing rods with 5% minimum silver alloy for copper-to-copper brazing. Use 45% minimum alloy for copper-to-brass and copper-to-steel brazing.