I am on the point of deciding on a new hot water cylinder and I am now
wondering about getting a "Superduty" cylinder - a cylinder with instead of
a primary coil of one tube, a cylinder having a coil with four smaller tubes
and hence greater surface area to transfer heat. Now the idea is to improve
efficiency by reducing cycling and also reducing the temperature of the
return flow and promote condensing.

" The installation of a Superduty will reduce boiler
operating times and cycling periods resulting in
savings of up to 40% compared with systems using conventional indirect
cylinders."

40% is I am sure BS but is a decent efficiency saving likely?

And before anyone suggests it - no I f***ing well do not want a combi.

H