4-way mixing valve

mattyc

I have an oil boiler in my home which is oversized that runs just one zone of baseboard and a tankless coil...As it is, the zone itself and the boiler short cycle all season. I want to install a "turbomax" water heater with the two extra tapings which will serve as a better means of hot water and also as a buffertank for the boiler to achieve longer burn times...Out of the turbomax (still on the heating side) I want to install a 4-way mixing valve with outdoor reset to achieve longer run times for the circulator and overall more efficient and comfortable heat...My two questions are...1) most manufactures recommend primary/secondary piping for 4-way mixing valves, Can the buffer tank still act as a hydraulic separator instead of doing primary/secondary? (I know I will still have to add a circulator between the boiler and buffertank)....Also 2) what valve do you guys recommend? I want to spend the money on the best equipment but from what ive been reading, It seams like Tekmar would need multiple controls to control the valve where as Tacos I series 4 way valve seams a bit "simpler". In your experiences what are the differences in the two control options or are there other options out there?