I have hot water baseboard heat. The galvanized pipe risers are coroding and rusting under the ceiling joists of my yet to be finished basement. Somewhere along the line someone decided to put in saddle valves on probablly to remove air from the line. They appear to have caused the rusting. Basically I need to replace the coroded pipe, which would be 12 total pieces. There are 6 feed line and 6 returns most less than 12 inches long. The system also has venturi T's to direct water flow I don't really know what thier condition is. I want to know the correct way to replace the risers. I feel that I could probably do it myself, either way I want to know how to make sure it's done right. I know of 2 ways after draining lines and cutting off water supply. Cut out old pipe with sawz all and either use:1. dielectric unions on each end with copper pipe soldered in the middle.2. or use the galvanized pipe with galvanized unions in the middle to spin them in.Any ideas??
This is beyond my skill set, but I had some radiator lines changed out in my basement that were hanging annoyingly low. They used copper piping, and was told that the unions weren't necessary like they would be with a house water line because it was essentially a closed system. I fortunately had this done just before copper prices skyrocketed, but for all I know maybe copper came down again. I don't really monitor copper prices.