BoilerFaultCodesYour boiler's computer and its remote control are having trouble speaking the same language, causing the system to stop working correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: System configuration: invalid. Invalid coding in remote control for the heating circuit.
What causes this fault?
This fault occurs when the boiler's internal computer receives conflicting information about how it should be operating. The most common reason is that a newly installed part or external thermostat hasn't been programmed correctly to talk to the boiler, or an electrical glitch has corrupted the system's memory. It essentially means the boiler has forgotten its own identity and shuts down as a safety precaution.
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 Fault 20 / 193 — 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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