BoilerFaultCodesYour boiler has likely experienced a glitch or internal hardware communication error within its main computer system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Three figure number example (Internal error)
What causes this fault?
This fault occurs when the boiler's main control board experiences a data processing failure or loses connection with internal sensors. It is typically caused by a genuine electronic failure within the computer chip or electrical interference disrupting the signal between components. While a simple reset may temporarily clear it, the code usually indicates that the internal hardware has reached the end of its reliable lifespan.
DIY fix possible
Locate the main power switch for the boiler and turn it off.Wait for approximately 30 seconds.Turn the power back on and press the 'Reset' button on the boiler fascia for 3 to 5 seconds.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 218 — 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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