Brian Elfert wrote:

....
My design has a drip leg at every outlet. The main line is about 25 feet
and I plan to have about 4" of slope.

Alternative, use a drop connection of two 90 street ells, first pointing
up, the second to turn it over for the outlet...condensate will stay in
the main header to be drained there...

My plan was to have a drip leg at the end of the main line, but that would
mean water could collect at the end of the main line where my elbow going
up would be. I better change things so I can drain the main line.

Use a tee w/ a drain valve below the supply connection instead of an
elbow...