Also been on a central heating project. Over 1000 litre thermal store, if that is what it can bee called. Needs more insulation, but that can come in time.
Going to have a WMO burner heating it, eventually. The way the weather is, it might be this week, because there is not much work I can do in this.
If I erect a bit of a canopy in the morning, to keep the rain off as I plumb it in, I might stand a chance of getting it fired up.
I somehow doubt it will be anywhere near as tidy a Jules' setup though.........