Hi my friend did you manage to resolve the issue.
I'm having the exact same problem with the same boiler as yourself.
There is a problem with the gas valve on some of the 8000 boilers . All owners will be contacted over the next 2 months to replace those affected . Not sure what is the issue with the gas valve. I would get Worcester back if you are unhappy but make sure explain the problem so the engineer solves it
Show us another picture of the connection on the right (& pipework).
It looks a right bodge and the pipe appears to have cracked.
The installer can come back and re-do for free or get a Gas-Safe inspection and they will force him to re-do.
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