I have been searching and searching for a how-to on the copper piping boiler pre-heat and have found the basic photos etc, but can't find the more in-depth info. I want to replace the high-pressure Teflon/plastic tube going from the high-pressure end of the pump to the boiler, including threaded ends, with a long copper tube.
What I hope you guys can tell me is:
What size copper piping to use? I have seen people talk about 10 and 6 mm ID
What kind of fittings are used to connect the copper pipe to the threaded elements? I have read 'compression fittings', but what size thread/gauge? BSP? 1/8"?
Where is the best place in the UK to get these parts from?
Is it worth doing/am I going to end up with a shiny indoor water feature?
Even if it's not worth doing, I think internal high-pressure plumbing is a good skill to have!