Choosing the Right MVHR Filter Grade: G3, G4, and M5 Explained

MVHR Filter Grades

Mechanical Ventilation with Heat Recovery (MVHR) systems are becoming increasingly popular in homes and commercial buildings. They provide a highly efficient method for controlling indoor air quality and help reduce heating bills. However, to maintain the system’s effectiveness, it is essential to replace the filters regularly. The most important factor to consider when selecting a replacement filter is the material grade, which is usually expressed as G3, G4, or M5. In this blog post, we’ll explore the different MVHR filter grades and the differences between them.

Firstly, let us briefly explain what an MVHR unit does. These units remove stale, moist air from your home and replace it with fresh, clean air. They have a heat exchanger which uses the heat from the stale air, to warm the new clean air. Some units are as efficient as 99%, so the heat you lose through the system is negligible and much more efficient than simple extractor fans.

Now let’s talk about the different filter grades:

G3 Filter Capabilities.

G3 filters are made from a synthetic fiber material and can capture particles as small as 10 microns in size. They’re the most affordable option, and are suitable for environments where the air is relatively clean, such as offices or homes with no pets. G3 filters are roughly 80% efficient at filtering dust mites and coarse dust and 40% efficient against mould.

G4 Filter Capabilities.

G4 filters are made from similar synthetic materials to G3, but they are more efficient at capturing airborne pollutants. These filters can capture particles as small as 3 microns in size and are ideal for homes with pets or in environments where the air quality is poor. G4 filters are roughly 99.9% effective at filtering dust mites and coarse dust. They are also roughly 80% efficient at filtering mould and 20% at filtering auto emissions and pollen.

M5 Filter Capabilities.

M5 filters are made from a more dense material that can capture pollutants as small as 1 micron in size. It is also a progressive material meaning the larger particles are captured first. This makes it ideal for environments that require a higher level of air filtration, such as homes in built-up areas and for those who suffer from allergies. M5 filters are roughly 99.9% effective at filtering dust mites, coarse dust and mould. They are also roughly 80% efficient at filtering pollen and 60% against auto emissions. M5 is the highest grade filter material that we offer for an MVHR unit.

Selecting the appropriate MVHR filter is essential for maintaining the indoor air quality and energy efficiency of your building. The grade required will depend on the level of air pollution in the environment, and the intended use of the building. Regular filter replacements and maintenance will also ensure longevity of the system and prevent damage caused by any debris build-ups.