Paris, France: Eurovent Certita Certification has announced introducing changes in the air-to-air regenerative heat exchangers certification programme.

According to the announcement, every year, certified air-to-air regenerative heat exchangers are selected and tested in an independent laboratory, providing trustworthy test results. These tests, it said, are then checked against the selection tools in order to ensure the reliability of provided data.

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In 2014, the announcement said that the certification body decided to change the way the results are checked, and aligned the method with the EN308:1997:

• Prior to 2014, the exhaust air inlet (11) and the supply air inlet (21) airflows were used as inputs in the selection tools.
• Since 2014, the exhaust air inlet (11) and supply air outlet (22) airflows have been used as inputs in the selection tools.

The announcement explained that as the airflow on the supply air outlet (22) is usually lower than the airflow on the supply air inlet (21), due to the Outdoor Air Correction Factor1 (OACF), the air velocity across the exchanger is lower, giving the calculation a better efficiency. Therefore, it is more likely that the efficiency will be out of the certification tolerances (defined in Rating Standard RS8/C/002-2016), added the announcement.

The certification body claimed that these changes have impacted the certified performances. In particular, the certified efficiencies (both temperature and humidity), the body said, have globally decreased when the products have remained identical. By using this method, Eurovent Certita Certification said that it is closer to the customers’ expectations, whose requirements are on the airflows coming from and to the building, and in line with the EN308:1997.