[pete c]

I have an indirect water heater which is heated by my boiler.

This works quite well in the winter when I have to run the boiler to heat my home, but, the rest of the year, at least half of it, it seem to me a rather expensive inefficient way to heat potable water.

An indirect heater, for those that are not familiar with it, is a system where you take hot boiler water and circulate it through a loop inside the water tank.

My idea is to plumb in a loop that goes from the indirect, up to the roof and back. It would use the existing circulator. It would cost me a few hunder feet of pvc tubing, some insulation and a few valves to isolate the boiler from the roof solar loop.

This system would circulate the boiler water only which transfers heat to the potable water via a coil in the tank. pumping the potable water itself up to the roof would likely end up turning the whole thing into a bacteria generator. it would also mean having to seperate it completely from the boiler loop.

My roof solar collector would simply be a long stretch of PVC/ABS pipe. If I use PVC, I would spray paint it flat black. What I am not sure about is how to configure it. I think maybe many lengths of thin pipe in parrallel would be most efficient.


I think such a system would give me more hot water than I could use about half of the year. I was also thinking that maybe a very well insulated small electric water heater as a booster might be a good idea for when I need hotter water or when the sun is not cooperating.