Pressurized solar water heater provides main pressure pre-heating via a high efficiency copper coil heat exchanger installed within the solar collector tank. The way in which the main pressure solar collector heats water is the same as the non-pressure solar collector. Instead of using the water in the tank directly, as the non-pressure does, the type uses a 36-60 meters copper coil heat exchanger inside the tank which provides more than 1.2m2 of heat for thermal storage.
One advantage of this system is that almost no water is introduced into the tank (apart from occasional topping up), so corrosion and scale buildup are almost totally eliminated. Tanks are designed for low to medium pressure applications, using gravity feed tank or pressure reduction valve. Direct connection to Mains Pressure water supply is not permitted. Please check your local building / plumbing regulations regarding the installation of water tanks.