VDI-EE 4650 Blatt 1.1:2023-06

Numerous heat pumps available on the market today can provide flow temperatures of at least 60°C for heating operation, and these heat generators are increasingly being used in existing buildings. However, the existing heat distribution and transfer often cannot be converted with reasonable effort in such a way that design flow temperatures of 55°C or less could be achieved. At the same time, the primary energy efficiency of heat pumps is constantly increasing due to the expansion of renewable electricity generation, so that a lower annual performance factor is justifiable as a result of higher system temperatures. The operating field of the standard heat pump in DIN V 18599 for the Building Energy Act ends at 60°C with the current revision. The standard therefore introduces the correction factors for a maximum flow temperature of 60 °C.

27.080, 91.140.10

This document has been replaced by: VDI 4650 Blatt 1:2024-02 .