when water relese trigger is pulled, a plastic bar running down, behind your clean water tank, makes contact with a "water release valve", moving the internaal workings of valve across, allowing water to pass from your clean water tank to the brush head and on to the carpet.
think of the valve as a door and the trigger the door handle...you want to let something in, you use the handle to open the door; to keep them out, you leave the handle alone
your water valve has probably stuck in the open position, allowing water to pass, directly from your water tank to your carpet...mine's jammed in the closed position.
try this link for replacement valve
http://www.spares2you.co.uk/Vax_V024_Side_Port_Valve
fred-a-stair
May 2011
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