knackered bath/shower mixer?

[anthonyberet]

Hi, I have a sudden problem at home. My bath/shower tap appears to have failed internally and now it wont switch to shower mode. It is a mixer (monobloc?) type which has a sort of cuff around the base of the shower-hose. - when you push the cuff down it is meant to switch to shower output, but the flow of water is now too feeble to get the shower head, even when the thing is not on its wall-fitting, because it is running out the tap-part to fill the bath.

My first thought is that I will have to replace the whole unit, but I am dreading having to do this as it will be very awkward to get at the nuts etc and I have never done that before.

Is it possible that there is some washer inside that can be replaced? - how would I get inside to check?

[John Rumm]

Very likely - there is often a disc mounted on a sliding rod that is moved with a plunger (or cuff in your case). These have a rubber 'O' ring round their perimeter that makes a seal against the body of the tap and diverts the water through the shower. Once this perishes and falls off the disc, it will no longer make a decent seal and most of the water carries on coming out of the tap. The solution is a new O ring.

Getting to it will be another matter! You may find the cuff pulls off revealing a large nut that you can take a suitable wrench to.