are you sure the tap is faulty it could also be an airlock
try this 1st if your taps in kitchen consists of only one spout open hot fully, cover spout with your thump under a towel, then open cold fully hold for as long as you can or you hear bubbles in the hot water tank and test.
if not
turn off mains if no other choice and run all taps till empty, remove valve from tap and replace with similar(hardware or plumbing spps)
ciaran
July 2009