Wood'nCoal wrote: by sting---->run 6 passes of 3/4 copper on a proprietary zone off the boiler.<-----
Good idea but not with copper, the chemicals in pool water (namely sodium hypochlorite) will erode the copper.
Your right -- sorry I missed the disclaimer -- happens more these days
and I suppose this will not be a good thing when it happens as stinky old black boiler water will mingle into the pool water -- YUCK
BUT -- for a cheep heat exchanger, some may accept the life cycle.
It all depends on your view - certainly this wouldn't be an option in a retail installation.