Division 3 General conditions for seasonal space heating energy efficiency

The useful efficiency values η_n , η_p and the useful heat output values P_n , P_p shall be measured, as appropriate. For solid fuel cogeneration boilers the electrical efficiency value η_el,n is also measured.

The seasonal space heating energy efficiency η_s shall be calculated as the seasonal space heating energy efficiency in active mode η_son , corrected by contributions accounting for temperature controls, auxiliary electricity consumption, and, for solid fuel cogeneration boilers, by adding the electrical efficiency multiplied by a conversion coefficient CC of 2,5.

The consumption of electricity shall be multiplied by a conversion coefficient CC of 2,5.