Worcester Bosch Short Cycling

Boiler cycles on and off rapidly without reaching set temperature.

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

Oversized boiler for system, Incorrect control settings, Blocked or undersized bypass, Pump overrun not configured correctly

Safety first: Short cycling can reduce boiler life and efficiency; it should be investigated.

Check controls: Ensure room thermostat and TRVs are set sensibly and not causing rapid on/off calls.
Keep at least one radiator fully open: This provides a bypass path for water when other TRVs close.
Engineer optimisation: A technician can adjust boiler parameters (e.g., minimum output, pump overrun), check bypass arrangements, and recommend system changes if the boiler is significantly oversized.

Medium 3/5

Automatic Bypass Valve

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