In article ,
John Rumm wrote:
Your existing cylinder is probably a slow recovery indirect type,
ideally suited to drawing a little heat when run in parallel with the
rads. A modern condensing boiler would be better matched with a fast
recovery cylinder run in S plan[1] configuration (so full output of the
boiler directed at the cylinder or the rads, but not usually both at
once).

I discovered that my fast recovery one will give a reasonable shower
starting with a cold cylinder. Not quite as hot as I'd normally have, but
OK if in a hurry. A sort of instant heater.

--
*Time is the best teacher; unfortunately it kills all its students.

Dave Plowman London SW
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