What the manual says
Manufacturer manualSynchronisation error, sequence
DIY fix possible
Switch off the boiler at its on/off switch and at the fused spur or isolator, then wait at least 5 minutes.Switch the power back on and wait for the boiler to finish its start-up sequence.Check the pressure gauge on the front of the boiler is between 1 and 1.5 bar, and top up with the filling loop only if it is low and you know how to do it safely.If the code returns, stop resetting it and book a Gas Safe registered engineer.
Avoid the next call-out bill
A cover plan would handle faults like 453: no call-out fees, no surprise bills.
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Related fault codes
All 131 fault codes on the Vitodens 050-W B0HA-25
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