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unless it has a energy saving value I'm sure my wife would veto it.



Efeciency gains depend on what you have now. The Buderus is a “side arm” heat exchanger. You run a loop off the boiler hot water to the tank and a zone valve regulates flow through the tank’s heating coils. Amtrol introduced these things about twenty years ago. Buderus has taken the technology a few steps further with increased insulation, larger coils and a unique holding tank design.

Their boilers are very efficient. They are a European manufacture, and Europe has been years ahead of the US in the utility business for decades. Out of necessity, they have to be innovative.