I've been looking at quite a few youtube videos on boiler making & repairs. Being a journeyman plumber I'm concerned when I see copper tubes being put in steel bulkheads. The electrolysis corrosion (dissimilar metals) is a big problem where copper pipe has been added to an old galvanized steel water system. Isn't that a major factor in the longevity of a boiler? They make special unions for steel water heater.copper pipe connections. When I was young my Dad (who was a plumbing contractor) taught me to use no less than a 6" brass nipple between the water heater & copper house plumbing (in the days before special WH connectors) I would be quit surprised if an inspector would pass such a boiler.