sorry oilman, i should have been more specific.
The boiler is a combi; chaffoteaux at maury stirling PP, I dont know how old it is, I have just moved in to the house.
The boiler does fire when the tap is turned on and the water does get hot if the flow rate is low i.e. the shower or a low flow from the tap.
However, if you try to run a bath or put the kitchen sink hot tap on full blast, then the hot water temperature is only luke warm.
The central heating works fine, the radiators get very hot, no problem there.
Also whilst showing the hot water is very hot, but it sometimes fluctuates in temperature, I am not sure whether that is the boiler or the tap, as the shower is run off a rather cheap looking telephone type bath tap.
Ok oilman, i think thats all. if you need anymore info, just say so
Cheers, Kev.