The hygiene of DHW installations and DHW heating systems is governed by EN 1988-200 and DVGW worksheet W 551. One of the main points in these regulations is protection against legionella. The rules for small and large systems differ.

Weishaupt's information bulletin explains the different requirements for small and large systems. A table presents an overview of five technical solutions to suit different heating and DHW demand profiles. These are evaluated with regard to their suitability and the likely investment and operational costs. Finally, each of the five technical solutions is described in detail and supported with practical examples and sample system schematics.

The information, titled "Legionellenschutz mit Weishaupt Wärmepumpen" (Protecting Against Legionella with Weishaupt Heat Pumps) is available in PDF format from the Weishaupt portal. A printed booklet can also be ordered directly from Max Weishaupt GmbH, 88475 Schwendi, Germany, from info@weishaupt.de, or from one of the 28 Weishaupt branch offices in Germany.