The boiler is from a brand new range by Glow Worm called Ultracom 2 that was introduced July 1st this year.
I am puzzled by the cover missing as it acts as a seal. There is no inner fire door. Where is the front cover? The wiring is dangerous if left like the picture. Has a roomstat been fitted. (And connected to the boiler).
Have you paid him?
Has the system been flushed, has a long term chemical Inhibitor been put in with the C.H. system water?
Have you been given the Installation and servicing manual with the Benchmark pages filled in completely, if you haven't you've no manufacturer's warranty. Which on this boiler is two years parts and labour.
As GrahamM said earlier this installer is an accident waiting happen.
You can always ask Gas Safe register to get one of their inspectors to check the work.