Filters are an essential part of any MVHR system. MVHR units need filters primarily to protect the heat exchanger from getting clogged up, which over time would affect the heat recovery efficiency of the MVHR unit. They also have an added benefit of filtering particulate matter such as pollen, dust and others from the incoming outdoor air (when using the higher Grade F7 Filter). We supply filters for a range of MVHR units.

How often do you need to change MVHR filters?

It is important to change your filters regularly (every 6 months on average) to avoid them getting clogged up. Exact timings will depend on the levels of indoor and outdoor air pollutants. With a constant volume MVHR unit, the fans will work harder and harder to achieve the same airflow they have been programmed to, so dirty filters can cause the unit to use more energy, make more noise and – in extreme cases – cause damage or failure to the fan motors.

Kitchen extract fleece filter

Filter for kitchen extraction vent

The kitchen extraction vent should always have an integrated filter in it to avoid getting clogged up. We always recommend a recirculating cooker hood to catch any fat in the air, but since the kitchen vent generally has the highest extraction rate in the MVHR system, any fat that does not get caught by a recirculating cooker hood can get sucked into the kitchen vent. Over time this will not only clog up the vent but also the inside of the ducts, which can create layers of dust and grease and can lead to the duct getting completely blocked.

The kitchen vents we specify use a cost effective filter (see Shop) and for this reason we think they are an essential component in the system.