Two AirMaster mechanical ventilation with heat recovery (MVHR) units from SAV Systems are helping to maintain good indoor air quality (IAQ) with demand controlled ventilation in a ‘landlocked’ classroom at Beech Hill Primary School in Newcastle.
The IT room at Beech Hill previously had opening windows but became ‘landlocked’ following building extension work, creating a risk that IAQ would deteriorate. The Mechanical Services department at Newcastle City Council therefore decided to introduce an MVHR system.
Several options were considered and AirMaster was selected for its ability to meet key criteria that included low noise, energy efficient performance, draught avoidance and minimal visual impact on the room.
The AirMaster units are semi-recessed into the 300mm ceiling void to minimise intrusion into the space. They are connected to the outside using horizontal ducting, designed to pass through the void space over an adjacent meeting room. The inherent low noise design of AirMaster units ensures that casing breakout noise does not exceed 35dB(A) at full throughput.
After visiting the site, Contract Manager Philip Welsh noted: “The teachers have commented on how quiet the units are when operating; they were on when I was there and I couldn’t hear them. The room temperature was comfortable, even with all the PCs operating. On the whole the school is more than happy with the units.”
The 2 x AML units are controlled through the Airling ORBIT control panel using a master/slave configuration, with demand control being achieved by combining a PIR occupancy sensor with a carbon dioxide (CO2) sensor. This combination of sensors ensures that the AirMaster units maintain minimum ventilation levels when the room is unoccupied, ramping up as soon as occupancy is detected. The IAQ is then monitored via the CO2 sensor to ensure that the average CO2 level does not exceed 1,000ppm.
By having heat recovery and demand control of ventilation, the AirMaster units at Beech Hill help to minimise energy consumption and carbon emissions.
AirMaster units also feature automatic temperature control of inlet air, using a combination of automatic by-pass and differential fan speed control. Inlet air uses the Coanda effect to stay close to the ceiling, entraining warmer room air as it moves along and falling slowly at the back of the room. By influencing air temperature and velocity, Coanda distribution effectively eliminates draughts.
Further information: www.sav-systems.com