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VDI 4650 Blatt 3 - Draft

Calculation of the seasonal coefficient of performance of heat pump systems - Fundamentals, terms, and defintions of multifunctional ventilation units with heat pumps

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German title

Berechnung der Jahresarbeitszahl von Wärmepumpenanlagen - Grundlagen und allgemeine Begriffe multifunktionaler Lüftungsgeräte mit Wärmepumpen

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Engl. VDI-Gesellschaft Energie und Umwelt
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For heat pumps to be eligible under the German Building Energy Act (GEG), various requirements must be observed, including mathematical proof of compliance with minimum values for the annual performance factor. For conventional heat pumps, e. g. with outside air or ground as heat source, the calculation can be done according to VDI 4650 Part 1 and Part 2. An analogous normative calculation procedure for determining the annual performance factor of exhaust air heat pumps is currently not available. The importance of exhaust air heat pumps is increasing throughout Europe, not least due to the required tightening of energy standards in new buildings as well as in refurbishment. The calculation of the annual performance factor of exhaust air heat pumps is based on the approaches of VDI 4650, taking into account the special features of exhaust air as a heat source (source and sink temperatures, limited air volume flows). The standard is aimed at manufacturers of exhaust air heat pumps, energy advisors and verification providers, trade associations, universities and other research institutes, energy suppliers.

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