Speaking of woodscrews, that FCU looks as if it is fixed with a single woodscrew rather than proper backbox mounting screws.
So either the proper screws have been lost, or the threads stripped. If its a metal backbox the screw makes the earth connection, so the correct screws should be used.
Also, the cable looks like its fixed (and I use the term "fixed" lightly here) using cable ties trapped under the slats. That's not acceptable. If it's in close proximity to hot pipes or goes to the boiler it should be heat resistant too. It could be heat resistant, but I can't tell by looking at the photo. However guessing from the state of everything else...
Also, what's with the rolled up earth wire?
So either the proper screws have been lost, or the threads stripped. If its a metal backbox the screw makes the earth connection, so the correct screws should be used.
Also, the cable looks like its fixed (and I use the term "fixed" lightly here) using cable ties trapped under the slats. That's not acceptable. If it's in close proximity to hot pipes or goes to the boiler it should be heat resistant too. It could be heat resistant, but I can't tell by looking at the photo. However guessing from the state of everything else...
Also, what's with the rolled up earth wire?