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Main Cartridge Repair Kit (720003100)
The Main Cartridge Repair Kit is the essential internal mechanism for the diverter valve, responsible for switching the boiler's flow between the central heating and domestic hot water circuits. Actuated by the diverter motor, this cartridge ensures that heat is delivered exactly where it is needed. Replacing the internal cartridge is a highly effective way to resolve sticking valve issues or "let-by" (where radiators heat up while running hot water) without replacing the entire hydraulic manifold.
Precision Mode Switching: Ensures immediate response when switching from heating to hot water for consistent performance.
High-Durability Seals: Includes specialized O-rings and internal seals designed to withstand high temperatures and pressure.
Debris Resistance: Engineered to operate smoothly even in older systems where sludge or limescale might be present.
Direct Replacement: A genuine-quality fit for part number 720003100 (also cross-compatible with 248733 and 7656807).
Compatible Models:
Main 25 Eco Elite POST SERIAL NUMBER MMH 1512
Main 25 Eco Elite PRE SERIAL NUMBER MMH 1512
Main 30 Eco Elite POST SERIAL NUMBER MMH 1512
Main 30 Eco Elite PRE SERIAL NUMBER MMH 1512
Main 25 COMBI ERP (SERIAL NO ENDING AC)
Main 25 COMBI ERP (SERIAL NO ENDING BC)
Main 25 COMBI ERP (SERIAL NO ENDING CC)
Main 25 COMBI ERP (SERIAL NO ENDING DC)
Main 30 COMBI ERP (SERIAL NO ENDING AC)
Main 30 COMBI ERP (SERIAL NO ENDING BC)
Main 30 COMBI ERP (SERIAL NO ENDING CC)
Main 30 COMBI ERP (SERIAL NO ENDING DC)
Main
A00580-02
