Ok, I had pretty well shifted my train of thought to doing an OWB when I finally got some honest input from the wife. Up until now, it's been "it doesn't really matter to me" which I know is never true. I was thinking she would prefer a less invasive to the house direction; if I picked the wrong one however I would invariably hear about it for years on and off. We were cleaning the basement this past week and she finally said that that she would prefer keeping it out of sight and having the chimney on the far side of the house vs an OWB unit and hopefully use less wood. That puts me back towards the Vedolux v37 which is fine and running the chimney. One of the basement windows will turn into a wood chute of sorts with a bin underneath. None of those a huge issue. The hurdle I've got is a 30" doorway at the top of a flight of stairs. Trying to get enough tanks down there and arranged for the amount of storage I would like seems tough and expensive. I'm really looking the direction of an American solartechnics 1100 gallon. There's a spot between some posts that's 89.5" wide which would fit it just perfect in between and it would fall between the boiler and the furnace. This leads me to how to get heat in and out of the tank. I could do a 150k btu coil from them for the boiler side and 100k btu coil for the furnace side. My concern is how much of the tank will be usable; will the heat really make it down the bottom and draw off the bottom on the reverse side? The other alternative I see which I can do about $500 cheaper I think would be 2 70 plate heat exchangers and dip tubes. In my mind, the dip tubes would allow me to deposit into the top and draw off the bottom better to utilize the entire tank? The piece I'm having trouble wrapping my mind around is how do I control those pumps and have them turn on and off with the correct pieces? The pump on the tank side of the HX plate would need to run whenever the boiler pump is running. Can it be run straight back to the boiler and tied in right where the circulator for it is? Or is there an additional controller that I would need to power it? I'm thinking there are 2 additional switches I need? One on the boiler side that if there's power to the boiler pump it turns on; when the boiler pump turns off it turns off. The second on the furnace side that would be tied into an additional thermostat upstairs. When it calls for heat it would power the pump on both sides of the plate HX and the furnace blower? Am I thinking correctly and if so what have people used? Also is there a specific pump that works well for the tank side of the plate HX? I am thinking stainless for sure based off what I read because that side is open. The boiler and furnace side of the plate HX could be cast because they would be closed?