What is MVHR?

MVHR is a ventilation system that both extracts stale air from wet rooms and supplies fresh, filtered air to living spaces. Unlike MEV, it also recovers heat from the outgoing air, making it much more energy-efficient — especially important in modern airtight homes.

How does it works?

1. Extraction of Stale Air

   • Just like MEV, MVHR removes air from bathrooms, kitchens, and utility rooms.

   • The stale air passes through a heat exchanger before being expelled outside.

2. Supplying Fresh Air

   • Fresh air from outside is mechanically supplied to bedrooms, living rooms, and other living areas.

   • This air also passes through the heat exchanger, so it is warmed (or cooled in some systems) before entering the home.

3. Heat Recovery

   • The heat exchanger transfers heat from the outgoing stale air to the incoming fresh air without mixing the two air streams.

   • This keeps the house warm in winter and reduces energy bills while maintaining ventilation.

4. Filtration

   • Both supply and extract air passes through filters to remove dust, pollen, and pollutants.

5. Balancing and Control

   • Proper commissioning ensures correct airflow rates to each room.

   • Many modern MVHR systems are demand-controlled, adjusting airflow based on humidity or occupancy.

• Heat recovery → energy savings.

• Controlled ventilation → better indoor air quality.

• Ideal for very airtight homes.

• Reduces condensation and mold risk.

• More expensive than MEV.

• Requires ductwork throughout the house.

• Needs regular filter cleaning and occasional maintenance

Key takeaway: MVHR gives you fresh air without losing heat, keeping your home comfortable, energy-efficient, and healthy.

MVHR DIAGRAM