BoilerFaultCodesYour boiler has detected an internal communication error, meaning the main control board is having trouble processing information correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: All Boilers
What causes this fault?
This fault occurs when the boiler's internal computer experiences a software glitch or a hardware failure on the main circuit board. It essentially means the 'brain' of the boiler can no longer send or receive the correct signals to operate the heating components safely. The most common reason is a corrupted memory chip or electrical degradation within the control unit itself.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 307 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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