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I think this might be my last leak, but it is in a difficult location. Any Help?
I think (hope) I found the last leak, but it is in a difficult place to fix. It is a 3/4 return line that is connected to 3 radiators, one radiator per floor, above that rusted out 90 (going up). That 90 is in crawl space and between floor joists that sit on that concrete shelf (the horizontal part of the pipe is resting on the concrete shelf for a couple of inches before it turns up), so there isn't much working room. It looks like the pipe rising up from the 90 is embedded in the concrete wall, but very close to the surface of the wall, and the wall is about 18" thick.
I could probably chip the concrete away from the pipe about 1 to 2 feet above that 90, cut the pipe there, and redo the rusted out section, but the pipe above the cut is still embedded in concrete and it would be a major job if I had to continue up to the next fitting.
Was it common to embed return pipes in concrete walls in the late 20's?