BoilerFaultCodesYour boiler is currently stuck in an incomplete setup mode, meaning the installation process wasn't fully finished or the system hasn't been properly coded.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Installation in unfinished state - Fault during compression joint valve
What causes this fault?
This fault occurs when the boiler's internal computer has not been told exactly what type of heating system it is connected to. It is usually triggered if a technician replaced a part or installed the unit but didn't complete the final software configuration steps. Until this digital 'handshake' is finished, the boiler stays in a safe standby mode and refuses to fire up.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like b1 — no call-out fees, no surprises.
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