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.
More About Boilers. A boiler uses natural gas, oil, or electricity to heat water or produce steam, which is circulated through a network of pipes into radiators, baseboard convectors, radiant floors or fan-forced coils. On average, 30 to 40% of household energy bills are from heating and cooling costs.