BoilerFaultCodesYour boiler has logged a note that a technician's diagnostic tool was plugged in while viewing the error history, but this itself is not a functional breakdown.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Service tool has been connected in the blocking error history menu
What causes this fault?
This code is triggered when a Gas Safe engineer has previously plugged a diagnostic 'Service Tool' into the boiler's circuit board while navigating the error memory menus. It is essentially a digital footprint left behind by a technician's computer and does not indicate a mechanical failure or a physical part breaking. Your boiler will continue to heat your home and water as normal, as this is simply a recorded log of past maintenance activity.
DIY fix possible
Press the 'Reset' button for five seconds to clear the displayMonitor the boiler to see if it resumes normal operationIf the code persists, check if any other fault codes alternate with 226
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A boiler cover plan would cover faults like 226 — 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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