sudden drop in water pressure in hot and cold taps

sudders999

Thanks for posting the pics...

southcoastrgi

it look like you have a combi boiler, the silver "pipe" is a magnetic scale inhibitor, where does the pipe go to the left, 2nd pic at the bott tee piece (that feeds the boiler & manifold), that pipe looks like the incoming supply

sudders999

It bends down and turns into a red pipe that goes down into the wall. It probably is the main supply