Buderus 3-Way Valve Cartridge 7099576

The Buderus 7099576 is a 3-way valve cartridge that forms the working core of the diverter valve section on Buderus combi boilers. The diverter valve is found only on combi appliances, where it switches the flow of heated water between the central heating circuit and the domestic hot water circuit. This cartridge is the moving element that carries out that changeover, so its condition directly affects how reliably the boiler selects between radiators and taps.

• Domestic hot water runs hot and cold, or the temperature swings without the tap being adjusted.
• Radiators heat up when only hot water is being drawn, or hot water is produced while the heating is running.
• No hot water at the taps even though the boiler fires and the heating circuit works normally.
• The diverter valve feels stiff, sticks in one position, or fails to move through its full travel.
• Water weeping from around the diverter valve body or the cartridge seating.

• Confirm the boiler model and GC number against the compatibility list, as the same appliance family can use different valve assemblies.
• Check the numbers already marked on the old cartridge against the alternative part numbers listed below before ordering.
• Inspect the seals and seating in the diverter valve housing while the cartridge is out, and renew any worn seals at the same time.