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.
Boilers come in two types the hot water and steam. Hot water boilers are small, compact, energy efficient and needs low maintenance. As to how they work, water is usually heated in boilers between 160 to 180 degrees Fahrenheit. The hot water is then circulated by pumps through pipes in the home or building. This heated water then warms radiators installed in the rooms and gives off the warm air.