Standard efficiency

The standard efficiency in accordance with DIN 4702 Part 8 was introduced in order to be able to compare different systems and installations for heat generation under standardised conditions. As a measure of the energy utilisation of a hot water boiler, it indicates the percentage of the energy used that is converted into usable heating energy over the entire year. The definition of the standard efficiency is based on the average outside temperatures and the corresponding heat demand frequencies in our part of the world. In this context, a boiler practically never operates at full load. Only partial load capacities are usually required. For this reason, the standard specifies five gauge points between 13 % and 63 % of the rated output for the standard efficiency. The five gauge points are distributed in such a way that each partial load measuring point is assigned the same heat output over the course of the year. For example, at an outside temperature of approx. 5 °C, around 30 % of the boiler’s rated heat output is consumed. The average from this measurement data provides the standard efficiency.

Standard efficiency in accordance with DIN 4702 Part 8