Ventilation – Graven Hill

Mechanical ventilation systems are installed within each property, with each unit being commissioned individually so that the amount of air moved is tailored to suit the performance required.

The system is designed to run continually on a constant trickle setting, which can be boosted via the kitchen and bathroom light switches. The spur switch for the ventilation unit is in the storage cupboard and should not be switched off, except for carrying out any maintenance and/or servicing. As part of the trickle setting, the recessed ceiling vents continually circulate air around the property and take stale air from inside the property and replace it with clean fresh air without the need to open windows.

The boost function enables the system to operate at a higher extraction rate, which is useful in situations where a lot of water vapour is produced in a short amount of time i.e. whilst cooking or bathing.

A summer/winter fan controller switch also forms part of the operation of the ventilation system. Switching the system to ‘summer’ places the system into the summer bypass function, whereby no heat is recovered. Switching the system to ‘winter’ places the system into the winter bypass function, whereby the bypass is disabled meaning the unit is constantly in in heat recovery mode.

The manufacturer, Nuaire, recommend that filters are inspected every 6 months and replaced every 12 months. A flashing LED will indicate that a filter change is required. This indication repeats every 12 months and will turn off automatically after 5 days. The maintenance of the ventilation system is the responsibility of the owner and should be carried out by a suitably qualified person. Please ensure the ventilation unit is serviced/maintained in accordance with the manufacturers guidance in order uphold the warranty, failure to do this will result in the warranty being voided.

Please see the below PDF version of the manual for further information:

Download – Ventilation – Nuaire MRXBOX-ECO3-SWMVHR – Installation & Maintenance Manual


Additional moisture in the air resulting from the drying out process, coupled with moisture produced by everyday activities may cause condensation to appear on cold surfaces, such as windows and walls. This can be reduced by:

  • • Covering pans during cooking and ensuring kettles are switched off after they boil.
  • • Drying clothes in well ventilated rooms where possible.
  • • Closing kitchen and bathroom doors to prevent moisture transferring into colder rooms.
  • • Avoiding the use of bottled gas or paraffin heaters.
  • • Wiping down surfaces where moisture settles.
  • • Maintaining a low background heat.

If the property is not being ventilated properly, then this will then result in a build-up of condensation. Excessive humidity or standing water on the floor can lead to damage through swelling (deformation and discolouration) which would not be covered under warranty.

Condensation can be alleviated by following the above guidance and by utilising the ventilation system effectively, which will in turn prevent ‘black spot mould’ from forming on the walls and behind cupboards.