How do you do a complete cold water system check for plumbing course?

im doing the same course and im stuck on the same thing.

I'm doing the same, when I purchased this course I was told that this scenario had a problem / fault and could not be answered. Best contact the tutors

I'm on same course, and if its scenerio 1, then the obvious error is that you cant check and fix the ball valve in the cold water tank, which is allowing excess water through and causing the overflow.

I managed to fix the ball valve in the CWSC by switchin off the mains stop valve under the sink and switichin off the service valve for the water storage and then draining the tank by running the bathroom cold water tap, then went back in the loft and was able to get to the ball valve to replace it.

Completing a cold water system check, i don't know what I'm doing wrong, inspected everything to no avail.

Best thing like the above said is to ask the tutor.