Try ringing a tradesman.....





Na hook a hose to the tap unhook the supply to the house(still leaving hose tap live) leave end going into house open(so you can back flush the line) and then go to your closest inside tap and then unhook the cold and adapt the open end(normaly have to go from 15mm brass to 20mm brass) then screw on hose fitting and plug in hose(to the cold water outlet for the tap inside) then go outside and turn on hose (which should be connected to the cold line inside) the if there is no blockage in that part of the line then the pressure and flow should be close to same as hose tap...and carry on to the next closest inside tap and repeat....visualy recording flow and pressure....hope fully this will at least give you a general idea on where the blockage is(if there is a blockage).



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