The CE mark, or formerly EC mark, is a mandatory conformity marking for certain products sold within the European Economic Area (EEA) since 1985. The CE marking is also found on products sold outside the EEA that are manufactured in, or designed to be sold in, the EEA.
Condensing boilers are water heaters fueled by gas or oil. They achieve high efficiency (typically greater than 90% on the higher heating value) by condensing water vapour in the exhaust gases and so recovering its latent heat of vaporisation, which would otherwise have been wasted.
A system boiler heats your central heating system directly and produces hot water for your cylinder. A system boiler, just like a regular (conventional) boiler works on the principle of stored hot water.However, a system boiler differs from a regular boiler in some important respects.n example of a central heating and hot water system layout using a system boiler with an open-vented hot water cylinder. View our system boilers. An example of a central heating and hot water system layout using a system boiler with a pressurised unvented hot water cylinder. View our system boilers.