Been toying with the idea of incorporating DHW into my boiler system. Have EKO 40 and waste oil burning buderus boiler in outbuilding. 500 gallons of pressurized storage in basement (one of those red preinsulated square ones new horizons sells or used to). I currently use a 40 gallon lp fired unit for DHW. I've been researching the idea of fitting one of those finned copper coil Water to water exchangers that bolt onto a boiler into my pressurized storage. I'm a fairly skilled welder and thought about removing the skin and insulation from the top of my storage and welding a custom made flange sized to one of those coils to bolt down to. I'm trying to avoid adding more pumps and this seems like a simple way to do it after the modifications are done. I would drain down the tank this summer when I'm doing some other repiping. What do you guys think?