How to choose and replace a ceramic cartridge in a mixer with your own hands

Recommendation points

• How does a single lever mixer work
• Varieties of cartridges or what to tell the seller
• Whether to dismantle the mixer
• Disassembly procedure and required tools
• Replacing the cartridge
• Reassembly, check operation

The wear and tear of the cartridge is the main reason for the breakdown of lever mixers. We have prepared instructions, following which you will get acquainted with the internal structure of lever mixers, understand the principle of their operation and easily replace the main functional element.

How does a single lever mixer work

Lever faucets have gained immense popularity primarily due to their ease of use. To realize the regulation of the pressure and temperature with such a small stroke of the control element, a rather interesting and simple mechanical scheme was used.

The earliest versions of flag faucets were a brass bar with a notch in the top and two channels for water flow. In the lower part of the channels there is an internal thread and a landing flange for stuffing box seals, where flexible water inlets are screwed. A polished ball with a small hole or recess is set in the recess of the blank under the additional clamp. Due to the displacement of the recess relative to the inlet holes, the regulation of the water flow between them is carried out.

This design turned out to be vulnerable to water of high hardness and the presence of mechanical impurities in it. Ball mixers quickly clog up in the absence of a filtration system, and due to the fact that the blank was almost one piece with the body, the valve was difficult to repair. They were replaced by cartridge mixers, which turned out to be much more convenient: replaceable cartridges are relatively inexpensive, and a layman with an adjustable wrench and a screwdriver can handle their replacement..

In the upper part of the cartridge there is a joystick-lever, rigidly connected with the mixer handle. In the lower part, the mixer has two inlet and one outlet, which are joined to the housing seat by O-rings. There are two ceramic plates inside the mixer, tightly fitting to each other and not subject to corrosion. The bottom one follows the shape of the round inlets and outlets. The upper one has an oblong hole, which, when the flag is moved vertically, moves forward, increasing the section of the duct. When the flag is turned, the upper plate also rotates, while the flow area of ​​different holes changes in the opposite relationship to each other.

For a simple replacement of a cartridge, there is no particular need to know all the details of its device. However, replacement during the life of the mixer can be performed several times. Perhaps, over time, you will collect enough spare parts so as not to buy a new replacement cartridge, but to assemble one of several old ones. You should also know that a sign of a cartridge malfunction is a leak directly from the mixer handle, leaks in other places indicate a breakdown of another kind.

Varieties of cartridges or what to tell the seller

The cartridges differ from each other in the shape of the shaped part, with which they are joined with the brass insert inside the body. In addition to the shape, size and location of the holes, incompatibility of cartridges can be caused by the presence of landing pins.

The easiest way to find a suitable replacement is to show the old defective cartridge to the seller. Often, you can also focus on the model and manufacturer, usually each company has its own specific shape of the mating parts.

Still, the best option is to get a couple of replacement cartridges right away when you buy a mixer. They are not too expensive, and the need for replacement will arise almost inevitably – this is what the design is designed for..

Whether to dismantle the mixer

In most cases, replacing the cartridge takes about five minutes and does not require dismantling the mixer body. The seat can be accessed from the top, but, as always, there are exceptions to this rule..

In general, it all depends on how long the mixer was in operation before the breakdown. To disassemble it, you will have to untwist several threaded connections. Rust and limestone deposits can become an obstacle, tightly clamping the threads.

Also, the mixer can be rotated in the installation hole of the sink or sink, if the locking groove is not provided. Holding the body with your hand while trying to stir the threads can be very challenging. It is even more difficult not to damage the chrome plating. Therefore, sometimes it may be necessary to completely dismantle the mixer, clamp it in a vice through a damp cotton rag for more convenient work.

Disassembly procedure and required tools

There is a small plug under the mixer lever that must be pry off with a thin flat screwdriver or knife. The screw head is located in a small recess under the plug, with which the lever cap presses against the cartridge joystick. To unscrew the set screw, you may need either a flathead or Phillips screwdriver, or a hexagon, it all depends on the specific model. If the screw does not give way, you can simply roughly pull the cap up, anyway the plastic lever inside will be replaced along with the cartridge.

When the lever is removed, for further work you need to twist the decorative plate. She, too, often “sour”, which forces you to use a pipe wrench. It is better to grip through a damp cloth so as not to peel off a rather “delicate” layer of a shiny coating.

There is a nut under the decorative ring – the main retainer of the cartridge. It is unscrewed with an adjustable wrench. Corrosion in this place is just the case when the mixer will have to be removed from its place, because the effort to unscrew it will have to apply a decent.

By unscrewing the nut, you get full access to the cartridge, it is now enough just to pull it up by the joystick lever. If not, pull harder, perhaps the seals are just stuck to the metal.

Replacing the cartridge

Before installing a new cartridge, check the condition of the molded brass part inside the housing. If corrosion has damaged the metal and the surface is no longer smooth, the cause of the leak may not be in the cartridge at all. Small defects of the metal surface can be eliminated with a sealant, but before that the mixer will have to be thoroughly dried, which means it must be dismantled first.

When installing a new cartridge, pay attention to the tightness. It should fit exactly into the mounting slots without any backlash. Sometimes the cartridge has a thin rubber band around it to seal the fit. This is typical for cartridges without a third, outlet..

Reassembly, check operation

After installing the gland, screw on the jam nut, but do not overdo it so as not to split the body. The functionality of the replaced part can be checked immediately: open the water supply to the mixer, check for leaks and try to open the tap. Usually, new cartridges have a soft smooth ride, if necessary, you can arm yourself with pliers or temporarily put on a lever.

If the cartridge opens both hot and cold water, and there is no significant difference in pressure when turning in both directions, close the duct, screw on the decorative ring and return the lever to its place, securing it with the locking screw. To prevent severe corrosion of threaded connections, lubricate them with small amounts of machine oil. When you put the plug in place, do not forget to turn it with the cold and hot water marks in the corresponding direction.