Andrews Water Heaters has supplied a SOLARflo water heating system, together with a direct gas-fired storage water heater to provide domestic hot water for the recently opened Orchard Park Primary School, Cambridgeshire's newest school.
This is located at Arbury Park, a new housing development situated to the north of Cambridge, which will ultimately provide a total of 900 quality homes. The school has been built to accommodate anticipated numbers of children when the development is completed and fully occupied.
In accordance with South Cambridgeshire Council's planning requirements, the school has been designed to achieve 10% renewable energy usage which includes both the Andrews' SOLARflo package as well as a dedicated wind turbine. These renewable energy components of the school's mechanical services have an educational as well as a practical use, demonstrated by the location of a display panel in the school entrance which shows the temperature at various parts of the system and the amount of energy produced.
Seven glazed flat plate solar collectors installed on the roof of the single storey building transfer energy to a 900 litre single coil cylinder situated in the plant room which pre-heats the supply to the adjacent Andrews CSC59 direct gas-fired storage water heater. This saves energy used for water heating, reducing the school's carbon footprint and, at the same time, making a significant contribution towards lower water heating costs.
The SOLARflo package comprises glazed flat plate aluminium tray solar collectors, together with a non-corrosive stainless steel solar cylinder. Each high efficiency solar collector has a 2.55m2 gross collector area which provides 90.8% transmission efficiency, 95% absorption efficiency and a low emission loss of 5%. The single coil water tank has a stainless steel solar heating coil and the complete package includes solar controls, pump station, expansion vessels, first fill of heat transfer fluid and collector mounting accessories.
The Andrews' CSC59 water heater is room-sealed, with a fan-assisted, balanced flue which draws in outside air and exhausts combustion gases via a single concentric flue. This feature was selected by the consulting engineer as her preferred option for its simplicity. In addition, this model of water heater offers a fast recovery rate which is ideal for installation in premises with demand which peaks at specific periods during the day. CSC59 models each have a capacity of 276 litres and a recovery rate of 1036 litres per hour through a temperature rise of 50oC.
Other features of the range include auto-ignition as standard, a concentric sealed flue system, up to 10 bar working pressure, the factory-fitted Hydrojet® tank recirculation system, cathode scale protection via a magnesium anode, fully automatic control and, on natural gas models, BEMS compatibility.
Of particular importance in a school environment is the elimination of legionellae bacteria in the water heating system. The patented Hydrojet water injection system is a cold inlet sediment reducing device that mixes and distributes incoming water most effectively. This maximises energy efficiency by increasing the first hour delivery of hot water while preventing temperature build-up at the top of the tank.
This is an additional safeguard to eliminating conditions conducive to the colonisation of Legionella bacteria in units that tested "Legionella resistant” by the National Measurement and Accreditation Service, (NAMAS). In addition, the design of the tank precludes legionella colonisation, even with a build-up of debris, as water at the bottom of the tank reaches at least the same temperature as the rest of the stored water. In this installation the Andrews water heater is also used to heat the solar cylinder to 60oC for legionella protection.
The Hydrojet® system makes a further significant contribution to the effectiveness of the water heater's anti-legionella functionality, as it is designed to increase turbulence, reduce sediment build-up, reduce thermal stacking and increase delivery.
The Andrews Water Heaters solar system equipment was selected to meet the Council's environmental design criteria by consulting engineers, Mouchel.
The SOLARflo system was supplied via the Bury St. Edmunds branch of Pipecentre and installed by specialist contractors Energise Engineering Ltd. The Andrews CSC59 storage water heater was installed by mechanical and electrical contractors,
Aylward EMS Ltd.
ANDREWS SOLAR WATER HEATING PACKAGE FOR NEW CAMBRIDGE SCHOOL
Andrews Water Heaters has supplied a SOLARflo water heating system, together with a direct gas-fired storage water heater to provide domestic hot water for the recently opened Orchard Park Primary School, Cambridgeshire's newest school.
