"Can you just give me some pointers"
YES, go and actually look at what you've been sent to do first it's probably far easier than you are dreading, then if you have a problem ring up.
I have looked at it and its not possible to fix it - WTF does that mean
oh - you don't have a clue and we need to send a competent sparks down there
how do men live there whole live in building services and still have no knowledge on anything
I once got a call to go down to reverse a 3ph pump that was running in reverse and when I got there the sparks on site advised me that it was impossible because all the cables in the new controls cabinet were the same colour.
happy to run my own firm now where I charge to fix the impossible.