hi every time i use my out side tap it starts makin a thuding sound the pipe jumps the water comes out then stops comes out then stops very raperedly it lasts for about five mins then sorts it self out can you help

chris, September 2008

some external taps have a non return valve built in to the body of the valve which might be sticking,remove bibtap from wall plate elbow and look into screwed end of tap,if there is a check valve built in then either remove or replace bibtap but you must have a double check valve fitted after shut off valve (usually inside house under sink).

steeveepee, November 2008