Study ECSI and central heating drain back

[Toine]

Hello everybody

It's always a pleasure forum !

I allow myself to create a post because I have a project to renovate a town house and I have a lot of questions about the heating system and DHW to set up ...
Having read the drainback system recently, I wonder if it is possible to apply it to a pipe boiler notably.
Even if a scheme would be better, the current idea is:
Solar panels in drainback and duct boiler in drainback supplying a first tank with ECSI exchanger with electrical back-up (bysun for example) with downstream a second tank / buffer tank of larger volume supplying central heating (direct pumping or with exchanger) as well as the panels and the boiler ...
The levels of the balloons would be common and adjusted with a minimum / maximum depending on the total volume of the circuits. Hence the importance of dimensioning the second, for a minimum variation in the first with ECSI.
The advantage is to have the same water for all circuits other than DHW, storage that is both large and differentiated (hot / less hot!), And few exchangers.
Are the questions of regulations ... and feedback if experience has already been made?
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