Heat Recovery

How motorised ventilation heat recovery (MVHR) works

MVHR removes and filters warm, stale air from wet areas such as kitchens and bathrooms whilst drawing fresh air from outside. The heat extracted from wet rooms is transferred to the incoming fresh air via a heat exchanger and distributed through ducting to habitable areas such as bedrooms and living areas.

The constant supply creates a refreshing indoor climate whist contributing to the heat load of the building. The motorised ventilation heat recovery (MVHR) system also removes home toxins, e. g. from new furniture, and filters pollen, which therefore do not even enter the house.

Advantages of heat recovery ventilation (HRV)

Buildings are becoming more and more airtight to keep valuable energy in.   A permanent and uncontrolled air leakage through air-permeable windows and doors does therefore not exist anymore.

Due to construction techniques that deliver nearly airtight interiors, moisture accumulates in the building from people showering, bathing, cooking or simply breathing or sweating. When warm and humid air condenses on cool surfaces in unventilated rooms, the risk of mould growth or spore formation increases. Moisture-related damage can have adverse effects on the human body and the building structure.

In addition, insufficient ventilation leads to an undetected decrease in oxygen concentration and increase in carbon dioxide concentration. The consequences are fatigue, general indisposition and lack of concentration.

Opening windows counters these negative effects, but leads to an energy loss. A far better alternative is the installation of a MVHR system which is becoming more and more important and is frequently an integral component of new constructions or modernisations.

  • supplies fresh air without draughts
  • removes stale, CO2-containing air
  • healthy and relaxing sleep
  • increases performance and concentration
  • protects from pollen and fine dust
  • prevents mould growth
  • Contributes to heat load

During the summer months fresh air can be introduced to the building without extracting the heat from warm, stale air and is referred to as a summer bypass. This provides cool, fresh air to enter bedrooms without the need to open window during the night and increase comfort levels.

The system runs silently throughout the year and boost functions are available but not always necessary.