NA 041

DIN Standards Committee Heating and Ventilation Technology and their Safety


Energy performance of buildings - Method for calculation of system energy requirements and system efficiencies - DHW instantaneous heat recovery- Module M8


This calculation procedure deals with instantaneous DHW heat recovery using a counter-flow heat exchanger between the drain water and the incoming cold water. The proposed procedure calculates the recovered heat, to be taken into account in the overall building energy performance calculation scheme. This calculation procedure doesn't cover storage heat recovery or the use of drain water as a source for a heat pump.





Planned document number

DIN EN 00228110

Project number


Responsible national committee

NA 041-05-01 AA - Design and energy performance of heating systems and water based cooling systems and DHW in buildings  

Responsible european committee

CEN/TC 228/WG 4 - Calculation methods and system performance and evaluation  


Dipl.-Ing. (FH)

Frank Lange

Am DIN-Platz, Burggrafenstr. 6
10787 Berlin

Tel.: +49 30 2601-2317
Fax: +49 30 2601-42317

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