When choosing an MVHR (Mechanical Ventilation with Heat Recovery) filter grade between G3, G4, and M5, it’s important to consider your air quality needs, system compatibility, and maintenance capacity. Here’s a breakdown to help you decide:
🔹 G3 Filter (Coarse Filter)
Particle Filtration: Captures larger particles like dust, hair, and pollen.
Efficiency: Around 80–90% for particles ≥10 μm.
Best for: Basic protection, rural or clean environments.
Pros: Low pressure drop, cheaper.
Cons: Doesn’t filter finer particles (e.g., fine dust, soot, allergens).
🔹 G4 Filter (Improved Coarse Filter)
Particle Filtration: Slightly better than G3; captures smaller coarse particles.
Efficiency: Up to 90–95% for particles ≥10 μm.
Best for: Standard residential use in moderate air quality environments.
Pros: Good balance of filtration and airflow, affordable.
Cons: Still not effective against fine particles (e.g., PM2.5).
🔹 M5 Filter (Fine Filter / ISO ePM10)
Particle Filtration: Filters finer particles, including many allergens and some PM10.
Efficiency: 40–60% of particles between 1–10 μm.
Best for: Urban areas, homes with allergy sufferers, or improved indoor air quality.
Pros: Better air quality, improves health and HVAC performance.
Cons: Higher cost, higher pressure drop (ensure your system can handle it).
✅ Recommendation
Urban or polluted areas: Go with M5 for better protection against pollutants and allergens.
Standard environments: G4 is usually the best compromise between filtration efficiency and system load.
Minimal filtration needs or limited budget: G3 may be sufficient, but it’s the least protective.
⚠️ Always check your MVHR unit’s compatibility .
