Our Hydras Unvented Cylinders are available in 4 different types that suit all domestic installations including installations of renewable energy systems such as solar panels. We offer a direct range, which heats the water inside via an electric element inside the cylinder and an indirect range which relies on a secondary heat source such as a boiler to heat the water but still has an electric element for back up. We also have Solar Indirect Cylinders which allow for connections of solar collectors as another source of heat to the Cylinder. Our Cylinders are guaranteed for 25 years and our accessories are guaranteed for 1 year. We offer a range of sizes to suit all homes, the smallest cylinder we have is a 125 litre cylinder and the largest is a 300 litre Cylinder. Unvented Cylinders are particularly useful for serving multi bathroom properties where instant hot water is required at improved flow rates. The hydras range of unvented cylinders are compact, affordable and easy to install.