Can Black iron NG supply run in close (1/2") parallel to a heating duct?
Black Iron NG supply line proximaty to heating/AC duct
Yes it can.
The ignition temp of NG is above 1,100°F.
not a problem
Just can’t run inside / through ducts.
As all said; yes it can.
P.S. Welcome to our forum, John…enjoy and participate. There are no stupid questions.