BoilerFaultCodesWorcester Bosch Fault 30 7 Fault Code
Also written as FAULT307 — same fault.
The Worcester Bosch Fault 30 7 fault code means: your boiler is having trouble managing the temperature of its internal water circuits, which will likely stop your heating and hot water from working correctly.. It appears on 2 Worcester Bosch models in our database.
Technical description: Mixer temperature sensor (MF) connected to IPM faulty. Mixer temperature sensor faulty.
What causes the Worcester Bosch Fault 30 7 fault?
This fault occurs when the boiler's internal computer loses track of the water temperature within its mixing circuit, often due to a failing sensor or a loose electrical connection. Without accurate temperature readings, the system shuts down as a safety precaution to prevent the water from becoming dangerously hot. The most common reason is a simple component failure where the sensor has worn out over time and can no longer send a steady signal.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Worcester Bosch models that show the Fault 30 7 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Worcester Bosch Fault 30 7 fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026