Can hear a hissing underground in the kitchen, kitchen floor wet with water about inch deep in parts, can hear water running in pipes running down wall in kitchen, presumably connected to header tank. Have turned water off but can still hear the noises

Duane, November 2008

Do you have a cold storage tank in the loft? IF the leak is off the tank it will continue to empty when mains water is isolated.

corgisteve, November 2008