5" main

Gary_17

Splitting 1 boiler into 2. Boilers only require 3" header. Will that work with the 5" mains or do we need to build 2 5" headers? Trying to avoid welding.

Steamhead

The boiler headers can be 3-inch

but the outputs from the boiler headers should go into a larger drop header. Dan has a diagram of this on page 67 of Lost Art.

nicholas bonham-carter

Welded headers effect on boilers

Best to use threaded steel, as there is a little play in the joints for expansion and contraction, which could put undue stress on the sections, and their gaskets.

There is the same problem with copper headers.

Using a drop header makes it easier to fit, and avoid expansion problems.--NBC