by ericmark »
Sun Feb 03, 2008 2:45 am
A combi boiler can be condensing or non condensing and a condensing boiler can be combi or standard.
Combi means it instantly heats hot water and no hot water cylinder or cistern is required.
Condensing means the exhaust gases are cooled to a point below boiling point and the latent heat of evaporation is used by the system. Some systems even use heat pumps and a three stage system to extract the last drop of energy but I have not seen them for sale in UK.
There is a third label either open or closed system most modern combi condensation boilers are closed system. But open systems are available in both combi and condensation systems.
Because duel fire/boilers or back boilers can be in the centre of a house condensing boilers can't be used because not really possible to relocate but to not use a condensation boiler would be silly unless something like that prevented it so they are not stocked and very hard to get one that isn't condensation type.
Who fits what is now becoming a problem as the plummer can no longer do the electrical part nor can the electrician do the gas part it seems that after years of trying to get workers to do work on allied trades to which the unions fought hard to stop it is now the government it's self who have returned us to one man one job again.