Guilty party

I voted by post last week so I haven't had to involve myself today. 
The new replacement part for my boiler arrived yesterday and so I called the plumber this morning while at work. As he could come this afternoon I headed home and worked on the laptop as it was fixed.
The first issue - the replacement part was not exactly the same so he had to deal with that.
The second issue - he had a complete meltdown when he thought he had blown the circuit board.

He hadn't. He just hadn't wired it correctly.

I now appear to have both hot water and heating and it is bliss.
I am also over £400 out of pocket. I could have done without that.