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.
Some boilers are designed. to burn more than one fuel (typically natural gas and fuel oil). Dual fuel boilers provide the operator. with fuel redundancy in the event of a fuel supply interruption. They also allow the customer to utilize. the fuel oil during âpeak timeâ rates for natural gas.