School children are alert to controlled ventilation
Comfortable and alert — the combined heating and ventilation unit below the window automatically introduces warmed fresh air to control the build-up of carbon dioxide in a new classroom block at a primary school in Swindon.
Energy-efficient and comfortable heating and controlled ventilation for a new classroom block at a school in Swindon is provided by the oXygen air-refreshment system from Jaga Heating Products. The system was specified by Swindon Borough Council for the classrooms at Haydon Wick Primary School to avoid problems caused by inadequate control of temperature and poor ventilation associated with steel panel radiators and opening windows. Jaga low-water-content Maxi LST radiators, incorporating oXygen units, were installed. Small fans in the units introduce fresh air, which is preheated during winter. The ventilation is controlled by a carbon-dioxide sensor in each room, which varies according to how many people are in the classroom. An exhaust system in the roof removes the right quantity of stale air. The active carbon-dioxide sensor system allows fans to operate only when there is a need for fresh air — ensuring economic operation. Tests carried out with the Building Research Establishment show that these radiators use 10% less energy than steel panel radiators. Independent testing in Holland has demonstrated that when used with a balanced oXygen air-refreshment system, savings of 20% can be achieved compared with natural ventilation. On a typical school day, the average carbon-dioxide concentration starts at around 600 ppm. By about 9.45 a.m., levels are approaching 800 ppm. As the morning continues, the levels rise further and, if uncontrolled, would considerable exceed 1200 ppm. The oXygen system controls the level of carbon dioxide — avoiding that lethargic feeling as the day progresses. Ian Bridge, principal mechanical and building-services engineer with Swindon Borough Council, says, ‘In line with regulations that now require school buildings to control carbon-dioxide levels, the installation of the Jaga oXygen allows Haydon Wick to continually monitor and be in control of their carbon-dioxide levels — creating a perfectly balanced environment.’