Boiler intermittently locks out with A23, especially when switching between heating and hot water.

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Possible Causes

Sticking diverter valve, Faulty diverter motor or microswitch, Debris in valve body, PCB not driving diverter correctly

Safety: Isolate power and allow the boiler to cool before working on water components.

Observe symptoms: Note if heating works but hot water does not, or vice versa. This helps confirm diverter issues.
Technician – inspect diverter valve: Remove the Beretta diverter motor head and check that the valve spindle moves freely by hand.
Clean or replace valve: If the spindle is stiff or jammed, clean or replace the diverter valve assembly.
Check motor and microswitches: Test the diverter motor operation and end switches. Replace the motor head if faulty.

Hard 4/5

Diverter Valve Assembly

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