Don
Dont agree combo is fine for a family of four , you need a large family to make use of a large tank of water .
Have recently moved from a property with large tank to a property with a combi and gas bill is now a few £ a month .
I never mentioned a
large tank of hw. We have a 100 some litre tank (120L ?), which is just enough for a bath, in winter, when the CW you add is at very it's coldest. When not used for baths, it will likely be used for washing up, hand washing and etc., if not used, it will be still hot the next day, and save reheating gas.
I used to run it available to reheat throughout the day, but when costs increased, I decided to limit it to 3pm to 7pm - to both save costs, and limit wear and tear on the boiler. The few pence worth of gas it costs, to reheat the tank doesn't really worry me at all, but as a purely academic exercise - I decided to drape an old bed quilt over the top of the yellow insulated tank, a few weeks ago. I didn't make any measurements, but the quilt does seem to have made a definite, and noticeable difference, to the temperature of the stored, unused hw next morning.
Anyone who comes here/ visits here, who are used to combi boilers, usually comment of how quick the hw appears at the tap, and how quick a bath can be filled.