The unvented hot water cylinder is a firm favourite among homeowners who possess a pressurised central heating system. Supplied with either an external or built-in expansion vessel, an unvented cylinder is particularly desirable as hot water is delivered under pressure and does not require a cumbersome gravity-fed water tank. New unvented hot water cylinders can handle your hot water pressure demands quickly and safely while offering manufacturer's warranties of up to 25 years. Please choose from our extensive range of unvented cylinders from all the leading brands today.