The Content Of The Article:

The mixer has replaced the classic mixer. More comfortable to use, but more complex, we can hesitate to intervene to fix it. It is possible...

Repair a shower mixer

Practical advice

• Before replacing the mixing valve, purge the installation as no foreign particles (welding, copper filings, etc.) should pass between the ceramic discs. Any scratch would be fatal and, in this case, it is the complete cartridge that will change.
• A cartridge is not a standard item. Rather than choosing a low-end reference where nothing is replaceable, prefer a known brand offering a serious after-sales service: you will be sure to find the spare part.

The cartridge, flow and temperature

A mixing valve has an element that manages the flow and temperature of the water. This essential device, the "cartridge", is formed of two permanently lubricated ceramic discs.

The use of ceramic inserts has improved the comfort of use and the efficiency of the faucets. Pierced and mobile, these discs move according to the position of the control lever to let the water run, more or less hot, and more or less. They ensure a good seal and are indestructible. Their operation is silent. But we can meet some dysfunctions; the most common being a drip at the outlet of the spout and, more rarely, an abnormal resistance of the control handle.

Changing the cartridge is not necessarily the solution

When a mixer leaks, it is often enough to change the valves. But when it comes to a mixer and you ask his opinion to a dealer of sanitary components, he advises in general to change the cartridge. Which is not always the cure for dysfunctions.

The cartridge, attached to the body of the mixer, does not allow any intervention. A continuous and uncontrollable flow of water would lead to its change. In our case, the leak occurred at the base of the cartridge. This suggests that this is a joint problem (photo 4).

The renovation of the tiles in the shower room made it possible to remove the mixer tap. This step is not mandatory: the repair can be done with a mixer in place.

Seals like new

The mixer tap is separated from the hot and cold water seals sealed in the wall by unscrewing the two connection sockets with a wrench. Water must be cut before any operation.

Disassemble the handle first, then the trim cover and the cartridge that is held by a flange or a large nut. In both cases, there is compression of the cartridge on its base with three O-rings which ensure the seal being lacking here. The simplest way would be to replace these joints. But they come with a new cartridge.

The old seals are therefore removed, descaled, coated with silicone grease and replaced. This allows in general to find a good seal. But they must be well settled in their homes. The O-ring for holding the trim cover is in DIY superstore. Take the old one: he will serve you as a model.

Unlock the handle

Unlock the handle

The mixer tap, it is easier to reach the locking screw of the handle, accessible by removing a plastic plug. Here, the tool is a 3 mm Allen key.

Remove handle and disc

Remove handle and disc

With the handle removed, we come across a plastic disk. In its center, a square fits on the lever acting on the cartridge. Unscrew the screw and remove the disc.

Unclip the cartridge

Unclip the cartridge

The hood of the cartridge is surmounted by a half-spherical head. It is held at the base by a defective O-ring. Remove the cover and release the screws from the cartridge flange.

Descale O-rings

Descale O-rings

The cartridge is held by its flange (on the right). The seal between its base and the mixer plate is ensured by three O-rings, here scaled. Sprinkle with hot vinegar.

Clean the platinum

Clean the platinum

Clean the platen. With a sharp piece of wood, scour each joint seat. Pass platinum vinegar and rinse. The new seal seals the two screws of the flange.

Coat platinum

Coat platinum

You can remove the seals from the cartridge and replace them on the platen by coating the whole with silicone grease. Preferably, keep for each joint its initial position.

Replace seals

Replace seals

The basic O-ring has been removed to assist in the placement of the cartridge. It will be replaced and capped by the hood hubcap. Tighten the two screws of the flange.

Reposition and fix the mixer

Reposition and fix the mixer

Reposition the mixer on the two wall outlets and screw the two sockets after replacing the two flat seals. Finish tightening with the key.


Video Instruction: Mixer shower problems: 4 most common mixer shower faults with repair tips.