I've seen, on the interwebs, that black iron piping can be used for primary boiler loops, especially when boiler itself is cast iron. But is black iron okay/recommended for modern condensing combi-boiler (Noritz NRCB180).
As far as I can tell, there is no cast iron in this modern combi, and the manual makes no suggestion or requirement for primary boiler loop plumbing, other than closed loop and pipe diameter.
If black iron can be used, is there any added maintenance that would not be required for copper?
To be more clear, in my case, I have only a primary loopback with no secondary loops (for now).
