The Andrews packaged approach to solar hot water
Renewable energy for domestic hot water — the Andrews SOLARflow package provides an approach to meeting planning requirements for the use of renewable sources of energy.
Andrews Water Heaters has incorporated the potential to use solar energy to generate domestic hot water in a package that is ready to install. SOLARflo comprises glazed flat-plate solar collectors, roof mountings, a duplex stainless-steel hot-water cylinder, control unit, pump station, expansion vessels and first fill of water/glycol solar heat transfer fluid. A package can be installed with an Andrews primary heating appliance such as the MAXxflow condensing storage water heater, a continuous direct-fired condensing water heater or a commercial condensing boiler. The primary heating appliance can also be supplied as part of the package for new-build and refurbishment projects. Andrews offers a totally integrated solution, including sizing the solar system right through to commissioning. The solar panels have a collector area of 2.55 m2, transmission efficiency of about 91%, absorption efficiency of 95% and emission loss of 5%. They have a 10-year guarantee for factory faults. A range of twin-coil cylinders is offered to operate with solar arrays from 10.2 to 17.9 m2. The package maximises the use of solar energy by preventing the primary heat source firing too quickly and also ensures that hot water is pasteurised before it reaches the outlets to prevent the development of legionella bacteria. Other equipment in the SOLARflo package includes the solar pump station, complete with temperature gauges, pressure gauge, flushing and filling device and de-aerator, cold-water expansion kit and a solar heat transfer vessel with a membrane rated at 100°C. Mounting accessories for pitched and flat roofs are also available. A package with evacuated-tube solar collectors is also being developed.