Unvented Cylinders
Unvented systems have no cold water tank – instead, the sealed hot water cylinder is fed directly by the cold water mains. This can offer much better flow rates, meaning your shower and bath performance should be higher.
Since you do not rely on gravity to move the hot water around, the unvented cylinder can be located anywhere in your property, removing the need for a cold water tank in the loft.This removes the potential freezing issue during our long cold winter periods.