BoilerFaultCodesYour boiler is currently stuck in its internal computer programming mode and hasn't been set up to operate as a heater yet.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Display shows uP on power on (PCB programming mode)
What causes this fault?
This fault occurs when a newly installed or replacement control board has not been told which specific boiler model it is living in. Because the same board is used across many different models, it remains in a 'blank' programming mode and refuses to fire until the correct configuration code is entered. The most common reason is that a technician has just replaced the board but hasn't finished the final software setup.
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 uP — no call-out fees, no surprises.
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