CHeSS central heating system specifications

CheSS was produced by the building research establishment BRECSU, in response to a request from the Heating Strategy Group of the Energy Efficiency Partnership for Homes, which recognised that one of the Key difficulties facing the domestic heating installation industry was a lack of common standards and understanding of what should be done to improve energy efficiency.

For almost 20 years, BRECSU has been promoting energy efficiency in buildings on behalf of the government. Since 1989, they have done this as managers of the buildings element of the Energy Efficiency Best Practice programme, on behalf of the UK's Department of the Environment, Transport and the Regions (DETR) and the devolved administrations.

CHeSS gives current recommendations for good practice, and best practice, for the energy efficiency of domestic wet central heating systems. Purchasers - consumers should use these specifications to ensure their heating installations will conform to current good or best practice. Installation engineers should use them to quote for systems of defined quality, this will enable the consumer to make informed comparisons between competing tenders.

It explains to purchasers and suppliers how the efficiency-critical components should be specified, using four simple names for reference - below. Follow the links to find out more.

CHeSS: System description HR1 & 2

Domestic Wet Central Heating System with regular boiler and separate hot water store (see note 3)

• CHeSS HR1 (2000) : regular boiler and hot water store system - good practice.
• CHeSS HR2 (2000) : regular boiler and hot water store system - best practice.

CHeSS: System description HC1 & 2

Domestic Wet Central Heating System with combination or Combined Primary Storage Unit (CPSU) boiler (see note 3).

• CHeSS HC1 (2000) : combination boiler system - good practice.
• CHeSS HC2 (2000) : combination boiler system - best practice