The vitiated air shall be extracted from the space using an energy efficient constant pressure principle via a variable air volume motorised damper/grille installed in each area, as detailed in the schedule.
The extract fan shall automatically vary its speed as the system pressure varies; the variation in pressure is caused by the opening and closing of the Nuaire CVD extract damper. The damper is autonomous of the fan and requires no field wiring connecting it to the fan. The damper positions are open (boost) and closed (trickle). When the damper is closed, the grille will allow approx. 8 litres/sec flow rate, as background ventilation. The inline damper has an integrated airflow sensor which continuously monitors and controls the amount of air being moved. The air volume is adjusted via minimum and maximum potentiometers on the side of the CVD damper.
The duct mounted damper CVD requires a 230V connection/power supply. Signal from 230V switch live i.e. light switch, PIR, humidistat etc.
Once commissioned and set to work, the fan will maintain the preset pressure by varying its speed as the ventilation requirement within each area varies i.e. as dampers open and close. If the requirement exceeds the maximum or minimum limit, the fan will remain at the design/ limiting speed.
Each acoustically lined low noise Single fan shall be fitted with an integral Ecosmart control inclusive of pressure transducer and inverter drive. The fans shall have the following energy saving and operational functions integrally installed within the fan unit, all components will be pre-wired and fitted by the manufacturer:
- Integral operating pressure adjustment (target pressure).
- BMS interface 0 - 10V.
- Volt free run & failure/status indication.
- 4no. low voltage sockets for interconnection of remote failure indicator.
Fan, integrated Ecosmart controls and associated sensors/controllers shall be manufactured by Nuaire.
- Optional trickle/boost flow rate.
- Externally adjusted settings.
- CVD helps balance system.
- MEMS provide precise measurements and control of flow rate.
The installer shall allow for all necessary ductwork transformations to and from the fan unit and any associated components in accordance with the manufacturers recommendations, DW 144 and general good practice.
Electrical installation requires the provision and connection of three phase sizes 15 to 19 inclusive.
A volt free run/fail status indication at the fan.
A single phase supply to the duct mounted damper version CVD/NRG.
A single phase supply to the transformer feeding the grille with integrated damper and PIR, the 12V output of which is connected to the grille.
The systems should be commissioned in the normal way and the operating or target pressure (inlet side of unit only) set via a potentiometer in the integral set-up box within the fan unit. This should be adjusted until the required air volume flow rate is achieved on the approved measuring device.
With units and spare parts in stock in our 100,000ft2 storage facility components and spares are on the shortest lead time possible. Nuaier has also invested in over £2.2M in sheet metal production machinery to ensure you get your AHU on time.