Glowworm Diverter Valve (Page 4)
The diverter valve is directional water device that only appears in combi boilers. It allows the hot water to be guided to the central heating system (radiators, etc.) or to the domestic hot water system (taps, etc.). This feature is what makes a combi boiler so popular due to the fact that a combi boiler wouldn?t require a cylinder to provide heating and hot water.