‘Regulation (EU)1253/2014 shall not apply to ventilation units which are axial or centrifugal fans only equipped with a housing in terms of Regulation (EU) 327/2011’, Article 1 (c). This implies that such products are considered ‘fans’ and shall be treated according to Regulation (EU)327/2011.
A working draft from CEN TC 156 WG 17 ‘Fans – Procedures and methods to determine the energy efficiency for the electrical input power range of 125 W up to 500 kW – Complementary element’ describes the term “housing” in detail as a casing around the impeller that guides the gas stream toward, through and from the impeller. The housing may include an inlet bell, an inlet guide vane, an outlet guide vane or an outlet diffuser. For examples of boundaries for different fan types (in line with the working draft). A fan can be with or without housing. Protective guards are not included in the measurements of fans (guards are removed for testing).
Ventilation units are by definition equipped with a casing (Article 2 (1)), which, according to the above, is additional to the housing in terms of Regulation (EU) 327/2011. This implies that the casing is defined as all parts of the ventilation unit that interfere with the airflow, in addition to the housing. For a ventilation unit including a fan without a housing, there will only be the casing interfering with the airflow. Products that would normally be called ‘box-fans’ or ‘roof-fans’ are considered ventilation units.
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