This document specifies the laboratory test methods and test requirements for the testing of aerodynamic, thermal, acoustic and electrical performance characteristics of ducted mechanical supply and exhaust residential ventilation units.NOTESuch units are referred to as bidirectional ventilation units in EN 13142:2021.This document is applicable to unit that contain at least, within one or more casing:-fans for mechanical supply and exhaust;-air filters;-air-to-air heat exchanger and/or air-to-air heat pump for air heat recovery;-control system.Such unit can be provided in more than one assembly, the separate assemblies of which are designed to be used together.Examples of different possible arrangements of heat recovery, heat exchangers and/or heat pumps are described in Annex A.This document covers ventilation units with continuous mass flows for each setting point.This document does not deal with non-ducted units that are treated in prEN 13141-8:2021.This document does not cover ventilation systems that may also provide water space heating and hot water that are treated in EN 16573.This document does not cover units including combustion engine driven compression heat pumps and absorption heat pumps.Electrical safety requirements are given in EN 60335-2-40 and EN 60335-2-80.