MC against heating pipes?

ynk1121 · Aug 5, 2023

Noticed an old cloth wire coming down the brick wall feeding an outlet on the opposite side of our oil burner is all fray. Was going to replace it with MC but the plumber that was here doing work (why I was back there to take notice of it) mentioned there is some new local rule that they aren't supposed to be using MC around the boilers because the armor conducts the heat and cooks the wires inside. This didn't make much sense to me. I thought NM and MC are both rated to like 90C. Wouldn't they both cook around the same temp? I googled but found no mention of such a rule. I'm located in Nassau County NY.

Megawatt · Aug 8, 2023

ynk1121 said:
Noticed an old cloth wire coming down the brick wall feeding an outlet on the opposite side of our oil burner is all fray. Was going to replace it with MC but the plumber that was here doing work (why I was back there to take notice of it) mentioned there is some new local rule that they aren't supposed to be using MC around the boilers because the armor conducts the heat and cooks the wires inside. This didn't make much sense to me. I thought NM and MC are both rated to like 90C. Wouldn't they both cook around the same temp? I googled but found no mention of such a rule. I'm located in Nassau County NY.

There is nothing in the 2023 edition of the NEC that says that you can’t use MC cable around boilers. I’m guessing that it is a requirement for the county or state that recommends that MC cable not be used on boilers. Good luck and welcome to the forum.