hot tap wierdness

[Whitling2k]

Hi all

Two plumbing questions in one night!!

Our hot taps have a strange feature - and I wondered if it's common - and if it's easy to fix?

When you run any of the hot taps in the house - the upstairs hot tap also starts to dribble water out. When the other tap is turned off - it stops dribbling!

wierd!

 

[arosindale]

Try really cranking the upstairs tap tight, then run the other taps.
I have seen this before, its something to do with pressure differences when the pressure drops at the upstairs tap due to the water being released at another tap in the system, however you would think this would have no effect on the miniscule amount of water left in the tap assy after the sealing washer..