Thanks for the compliment. I'm learning as I go. The real test will be under pressure lol. Yes, that will thread into the hot outlet of the boiler jacket. There are a few galvanised fittings provided by Tarm for the pressure relief valve. I'll have a few more pics as I go. Should be able to get the boilers circulator, heat exchanger and emergency dump zone plumbed. Gotta run to get more copper pipe right now and run a few errands.