Mechanical ventilation with heat recovery

8.3.9Commissioning and balancing

MVHR design, materials and sitework shall be tested and commissioned in accordance with the commissioning schedule.

Upon completion of the installation, MVHR systems should be protected from dust during the construction of the home. Where possible the system should be switched off and dust covers applied to air valves.

Prior to completion of the home, the system:

  • including ductwork and filters, should be checked to ensure it is clear from dirt and dust that may have accumulated during construction
  • should be commissioned to confirm performance
  • should be adjusted by using the air valves and controls to achieve the correct balancing and airflow rates
  • should have air valves locked in position after correct commissioning and balancing.

Where the system cannot be balanced using the air valves and system controls, the complete system should be checked to ensure that it complies with the design.

Any changes from the design should be referred back to the designer. Adjusting the fan speed above the designed output may result in noise disturbance, and should be avoided.

A copy of the commissioning certificate should be made available to NHBC upon request.