replying to IMM, Peter Clarke wrote:
interesting, I have a similar issue. But I would add that my concern is people
downstairs at breakfast time flushing loos and using mains cold at the kitchen
sink; this will reduce pressure and flow to the showers if everything depends
on incoming mains. In my case I am going to be using 2 tanks in the loft to
supply the 2 ensuites only. The main drawback will be the heat loss from the
existing combi , on its long journey to the new DHW cyclinder that I am
installing for the ensuites, and that in summer some of my central heating
flow/return will be running hot just to get heat to the DHW cylinder.

--
for full context, visit http://www.homeownershub.com/uk-diy/...-s-111292-.htm