Solar Thermal Kits
To make life as straightforward as possible when ordering a system, Grant has introduced a series of kits that meet most situations. These simply consist of collectors, roof-mounting system, expansion vessel, pump station, control panel, pipe connections and solar fluid. To accompany this, an unvented twin-coil cylinder for the hot water will be necessary, which again can be supplied by Grant. For more information, see the Grant Cylinder range (click link to cylinder product page).
Bespoke kits of any size can be designed to suit almost any application.
Collectors
Grant Solar Thermal collectors incorporate self-cleaning glass and are available in two models. The Aurora collector has a durable aluminium frame with a silver anodised finish. This contemporary look is a stylish feature to accentuate your property and looks great when used on dark roofs like slate. The Sahara collector also has a durable aluminium frame, but with a bronze finish. This blends with most roof types, but looks especially good on a red tiled roof.
Grant Solar Collectors have a total area of 2.32m2. As a rule of thumb, when sizing a system, you should allow 1.0-1.3m2 of collector area, per person. Cylinder requirements are 50-60 litres capacity per m2 of collector area. To simplify this, for a 2-Collector system of 4.64m2, you would require a cylinder of approximately 200 litres. This would be sufficient for 4 people.
Components
Solar Controllers
The Grant GSD1 and GSD2 Differential Solar Controllers automatically manage the operation of the Solar Thermal System. Monitoring the temperature in both collector and cylinder, they operate the circulating pump only when the difference in temperature will provide efficient heating of the hot water. They will also stop the circulating pump if the temperature in the collector exceeds the maximum set or, if the cylinder has reached the required temperature.
The Grant GSD1 controller is used where the collectors are located on the same side of a roof – such as with a South facing installation, whereas the Grant GSD2 is used where the collectors are located on either side of a roof – such as with an East/ West facing installation. Both solar controllers monitor and display the amount of solar power produced by the system on a daily and cumulative basis. Amongst other features the GSD2 controller can display the collector and cylinder temperatures and also incorporates a pump kick facility which activates the pump for a short period each day to prevent the possibility of seizure if not operated for more than 24 hours.
Expansion vessel
Available in 18 and 25 litres, the expansion vessel connects to the Solar Pump Station by a flexible hose. It incorporates a special membrane selected to withstand the higher temperatures found in solar thermal systems.
Solar Pump Station
The Grant Solar Pump Station houses the 3-speed circulating pump, along with all other control components, in an insulated expanded polypropylene foam enclosure designed for vertical wall mounting.
The flow and return ball valves incorporate temperature gauges to monitor return and flow temperatures and have integral anti-gravity brakes to prevent gravity circulation around the circuit when the pump is stopped. The air eliminator with manual bleed screw allows for rapid air removal from the sealed system. The 6 bar pressure relief valve is mounted on a manifold with the system pressure gauge and expansion vessel connection.
Filling and flushing of the system is made easy by the combined fill and flush valve assembly and the adjustment of fluid flow rate is simple using the integral flow indicator.
Solar Fluid
The Grant Solar Fluid is an odour-free, non-toxic 40/60 glycol/water solution, developed specifically for Solar Thermal applications to protect systems from freezing. The nitrate, phosphate and ammonia free fluid has been formulated to remain stable over long periods of time and is also a good corrosion inhibitor. It is available ready mixed in 10 or 20 litre packs.
