Tania. Are your two showers electric, feed from a Combi Boiler or from a header tank (in this latter case it is likely that your house has a 'copper cylinder' to store hot water). They could also be from a header tank with and electric 'power shower pump'.
If they are electric then these showers are feed directly off the relatively high pressure water mains that comes in from 'the street'.
Still assuming they are electric they could both simple have a leaking valve - which just leaks (needs replacing). But, would you say the cold 'water pressure' in your house is 'high'. When you turn the cold kitchen tap on does the water flow with great gustto? Electric showers should beable to withstand high pressure but if yours is exceptional try turning your 'mains cold water stoptap' down a bit. This stop tap is normally under the kitchen sink so have sink cold tap fully open and you will see/hear the 'flow reducing as you make small turns (clockwise) of the stoptap (stopcock) under the sink. This reduction may stop the showers dripping. They will not stop dripping straight away - best to opperate them and shut down again AFTER you've made reductions to the undersink stoptap. Note:- this fix is what I call 'two wrongs to make a right' and if you close that 'under sink' tap too much the showers likely will not work at all. What we are doing here is trying to reduce the pressure (just a little) to the showers. The proper way to 'reduce pressure' is to install a 'pressure reducing valve', but turning the MAINS stoptap down a bit goes some way to mimicing this.
David Clay
January 2009
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