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Wet returns rusted and 7" nipple stuck in OLD cast iron boiler - How to remove nipple?
See pics - I've got this old boiler which I'd like to have limp along for another couple of years. - Problem is leaking in wet returns and especially where 7" (approx) nipple goes into boiler. Thought I'd cut the 7 incher at the boiler then try to remove the stub left in the threads, then as backup plan I thought I'd be able to have a welder weld a nipple to a plate and weld that to the boiler. Can't find a welder that would do it.
The plan is to replace both wet return pipes that join into this 7" pipe and the pipe.
Any thought on how to proceed?
Also, if I replace boiler, what, roughly, efficiency would I gain do you think?