BoilerFaultCodesYour boiler's internal computer brain has encountered a communication error and is preventing the system from starting for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Heat control module (HCM) potentially defective – reset the appliance
What causes this fault?
This fault occurs when the boiler's main control board loses its connection with the internal identity chip that stores the appliance's specific settings. It is often caused by a temporary electronic glitch or a physical failure of the heat control module itself, which prevents the boiler from knowing how to safely fire up. Because the brain cannot verify the boiler's hardware, it shuts down the system as a safety precaution.
DIY fix possible
Locate the 'Reset' button on the boiler control panelPress and hold the button for five secondsWait for the boiler to restart; if the code clears, monitor for recurrence
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A boiler cover plan would cover faults like EA261 — no call-out fees, no surprises.
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Worcester Bosch CDi Classic is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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