BoilerFaultCodesWhat the manual says
Manufacturer manualDisplay 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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Avoid the next call-out bill
A cover plan would handle faults like uP: no call-out fees, no surprise bills.
Affiliate links. We may earn a commission at no extra cost to you.