Help! Mixer tap in bathroom

[Shannaratiger]

I have a mixer tap in the bathroom. Over the last few days the cold tap has been turning less and less. We now have no cold water into the bath at all. The hot tap and water is fine!

the cold knob needs to come off. There is probably a brass hairpin-shaped clip that has come out of its groove. If you look at the hot side you will see how it is meant to go together.

I recommend that before you take it apart, you get some Silicone Grease (you may have to go to a plumbers merchant) and you dismantle and clean all the parts with a green nylon scourer, and reassemble with the grease on all moving parts. It probably went wrong because it was stiff. You will need a selection of metric spanners. Try to use ring spanners rather than open-ended, and avoid adjustables if you possibly can. The parts are made of brass which is soft and easily damaged. Put a towel in the basin to catch loose bits and prevent scratching or cracking it. Your assistant must hold the tap steady against your spannering force.

If your tap has a quarter-turn then it has ceramic discs. These are more troublesome. You might be able to get a new cartidge to match from a large plumbers merchant, they vary a lot. If you know the brand and model of the tap you might get one from the manufacturer. The price may surprise you. Before you screw the cartridge back in, wrap a few turns of PTFE tape round the thread to prevent leaks and make it easier to remove next time.

You must of course turn off the hot and cold supply to the tap before you start work. If you are lucky there will be a ball-o-fix type valve on the supply pipe under the basin, you turn the slot with a flat screwdriver so it is across the direction of flow for off.

There is probably a how-to-do-it on Videojug.