THERMOSTATIC MIXING VALVE: HOW TO REPLACE THE THERMOSTATIC CARTRIDGE?
The thermostatic cartridge is an element integrated into the thermostatic mixing valve. The slightest failure can affect the normal operation of the latter. If the thermostatic cartridge is clogged, a simple cleaning is enough to remove the impurities. Otherwise, it needs to be replaced. In any case, always remove the thermostatic cartridge. This is the only way to detect the origin of the malfunction. If you have a problem with your thermostatic mixer, we explain how to replace the thermostatic cartridge. You don't have to seek professional help. Also, find out what to do if your thermostatic mixer isn't working.
Usefulness of a thermostatic cartridge.
The thermostatic cartridge is an integral part of the thermostatic mixer. Its role is to regulate the temperature as well as the flow of water delivered by the mixer. Despite a possible variation in the flow of water in the housing, you can always benefit from a constant temperature, thanks to the thermostatic cartridge. The latter is often of a standard form. This facilitates its adaptation to most mixer taps.
Characteristics of a thermostatic cartridge.
The thermostatic cartridge has a cylindrical shape and is usually made with ceramic or metal. It is made up of a head with a variable diameter depending on the mixer model. Three O-rings guarantee the tightness of the cartridge after installation. Its metal or ceramic casing has three holes allowing the distribution of cold water, hot water and mixed water by the thermostatic mixer.
In addition, the thermostatic cartridge is also equipped with an axial rod which is doubled by housings on both ends. In order to facilitate its control by the user, it is equipped with a control element. Some models have a check valve located between the mixing chamber and the inlet ports.
Replacing the thermostatic cartridge.
Note that the replacement of a thermostatic cartridge can be done by anyone. It does not require any special plumbing knowledge. You just need to bring a flat screwdriver and a 6-sided wrench or even a pair of pliers.
Remove the thermostatic cartridge.
Before starting the intervention, it is strongly recommended to turn off the water supply. This will save you from inconvenience in the bathroom or in the kitchen. Then, the mixing valve must be emptied by opening the flow control. The next step is to disengage the temperature control knob. Indeed, the thermostatic cartridge is located just inside. To do this, you must first remove the screw cover using a flat screwdriver. After removing the fixing screw, you can remove the joystick. Now you can access the thermostatic cartridge. Using a hex key, remove the head locking screw and remove the cartridge.
Checking cartridge status.
Checking the condition of the cartridge is necessary to know if it needs to be replaced or if cleaning is enough to solve the problem. If the thermostatic cartridge is heavily clogged, you must immerse it in white vinegar for several hours. Before rinsing, take care to brush it gently to get rid of tartar permanently. Next, check the condition of the O-rings. You can now install the thermostatic cartridge to check if the problem is solved. Otherwise, it will have to be replaced with another one.
Choose the right cartridge.
You can find a replacement cartridge at DIY stores in the plumbing department. Otherwise, opt for specialized sites. The price usually varies between €12 and €100 or more depending on the brand, model or quality. To make sure you have the ideal model, you must note the brand and the reference of the thermostatic mixer.
Install the new thermostatic cartridge.
Before installation, do not forget to grease the joints with silicone grease for taps. Then, insert the new head in its housing while making sure that the fixing holes coincide perfectly. Tighten the cartridge head screw using the Allen key. Next, secure the control knob screw using a flathead screwdriver. All that remains is to put the screw cover back in place.