What type of water storage system requires a gravity-fed mixer shower?

A gravity-fed mixer shower operates effectively in an open vented system because this type of system relies on gravity to supply cold and hot water from storage tanks. In an open vented system, the water is drawn from a cold water storage tank and a hot water cylinder, both typically located in loft spaces or elevated positions. The gravitational force allows the water to flow down to the shower mixer without the need for pumps or additional pressure, which is essential for the proper functioning of a gravity-fed mixer shower.

In contrast, other systems are designed differently. Pressurized systems typically utilize pumps for water distribution and do not rely on gravity, whereas sealed systems operate under pressure and do not require venting. Combination systems provide immediate hot water without the need for a hot water cylinder, which also makes them unsuitable for gravity-fed applications. Thus, an open vented system is the only compatible system that supports the gravity-fed mechanics of the mixer shower.