Do I have to replace the filters currently installed inside the air conditioning units?

In order to guarantee the filtration efficiency of the installed filters, it is recommended to proceed with the ordinary maintenance intervals.

In this way, the filtration properties of the devices will remain constant. If necessary, it is still possible to proceed with the installation of high efficiency filters, such as the electronic filters available for the Rooftop and Zephir range, which guarantee very high filtration efficiencies (ePM1 90% - ISO EN 16890) with very low pressure drops.

For further information and support, please contact Clivet sales representatives https://www.clivet.com/en/sales-networ

In this emergency period, can changing the indoor temperature and humidity set points help fight the SARS-CoV-2 virus?

The SARS-CoV-2 virus is very resistant to changes in environmental conditions and it weakens only at temperatures higher than 30°C and relative humidity greater than 80%.

Unfortunately, these parameters are not acceptable inside buildings and may be dangerous for human health. 

Therefore, it is recommended to keep the indoor parameters unchanged while continuing to guarantee correct and normal maintenance of the plants.

How must we manage the air renewal plants?

As indicated by numerous directives, to lower the indoor concentration of bacteria and viruses, it is recommended to increase the fresh air flow rate as much as possible.

Furthermore, it is suggested to keep the plants active from 2 hours before the start of the occupation of the buildings and for another 2 hours after the end of the occupation.

For the remaining hours, it is advisable to keep the air renewal systems active at a lower speed than the nominal one.

The air extraction systems in correspondence with the toilets must always be active.

Electronic filters are an efficient way to avoid the diffusion of bacteria, but are they efficient to limit the propagation of viruses too?

Electronic filters capture particles from 0,01 µm to 100 µm with a variable efficiency that depends on the speed of air that passes through them. With an average speed of 2,5 m/s they are classified according to UNI EN 16890 PM1 90% (efficiency higher than 90% on particles with dimensions lower than 1 micron) or PM2,5 95% (efficiency higher than 95% on particles with dimension lower than 2,5 micron). 

Electronic filters also have a high microbicide power thanks to their high efficiency on sub-microbial particles. This is due to the destruction of the external membrane of bacteria/virus caused by thermoelectric shock when the ionized particles come in contact with the bulk blade located within the uptake section. 

The concentration of some common bacteria’s were measured before and after the electronic filter and the efficiency, certified by ILH Institute of Berlin: the efficiency is between 98 and 99%

It is important to point out that it's possible to reduce the risk of COVID-19 infection in confined spaces, which has an air conditioning system, combining an efficient air filtration system with a high air renewal rate and with a meticulous respect of the Governments' s rules of social distance, hands and surfaces hygiene.