The European standard series EN 13141 specifies methods for the performance testing of components for use in residential ventilation systems to establish the performance characteristics as identified in EN 13142. This European Standard does not contain any information on ductwork and fittings which are covered by other European standards. The standard can be used in the following cases: - laboratory testing, - attestation purposes. Part 7 of EN 13141 specifies the laboratory test methods and test requirements for the testing of aerodynamic, thermal and acoustic performance, and the electrical performance of a mechanical supply and exhaust ventilation unit used in single dwellings. It covers units with one or more casing that contain, at least: - supply and exhaust air fans; - air filters; - air to air heat exchanger and/or exhaust air/air source heat pumps for exhaust air heat recovery; - control system. Such equipment can be provided in more than one assembly, the separate assemblies of which are designed to be used together. The different possible arrangements of heat exchangers and/or heat pumps are described in Annex A. This standard does not deal with non-ducted units, reciprocating heat exchangers or units which supply several dwellings. This standard does not deal with ventilation systems that may also provide water space heating and hot water and units which include combustion engine driven compression heat pumps and absorption heat pumps. Electrical safety requirements are given in EN 60335-2-40 and EN 60355-2-80. The European Standard series EN 13141 has been prepared by CEN/TC 156 "Ventilation for buildings". The Working Committee responsible for the German version of the standard is NA 041-02-51 AA "Lüftung von Wohnungen" ("Residential ventilation") of NHS.