Can I use copper to replace leaking return?

Steve Garson

My neighbor's steam boiler just started needing three refills a day! It is only two years old. I helped him troubleshoot: Air vents are fine; filled boiler to the top and there are no cracks. That leaves the 70 year old under concrete return.

A plumber wants $1800 to replace the returns; two days work. I was thinking that we might put in some sweat equity and run copper along the walls with the right pitch and leave the connections to the present system to the plumber.

Is it acceptable to use copper for the wet return? Is 3/4-inch adequate, or must it be larger? Is there much of a cost of material difference between black iron pipe and copper?

FRANK_24

1 1/4" type L copper tube should be used. The material may cost a little more, but the savings is in the time. No problem using copper for a wet return.