Faucet Cartridge Fundamentals
tip If you need to replace the hot or cold cartridge on a faucet, we recommend replacing both cartridges at the same time. This will save you time, money, labor cost, inconvenience, frustration, and hassle.
There are a variety of cartridges which vary in their structure and function.
What is a Faucet Cartridge?
A faucet cartridge is a device within a faucet that controls the flow of water.
What is the Function of a Cartridge?
The function of a cartridge is to control the quantity of water flowing through a faucet and/or the temperature of the water. Cartridges are designed to provide precise control over water temperature and flow, contributing to the efficient functioning of the faucet.
How Cartridges Work
Many faucet cartridges are integrated within valves, which provide the structural support from within which the cartridge can perform its water regulation function.
A cartridge is connected to a handle and resides within a valve, which resides within the faucet.
Types of Faucet Cartridges
Water Volume Control Cartridges (Quarter Turn Ceramic Disk Cartridges)
Volume control cartridges turn the water on and off, and control the quantity of water flowing through a faucet.
Quarter Turn Ceramic Disk Cartridges
Hot and Cold Water Mixing Cartridges (Thermostatic Cartridges)
Thermostatic cartridges are part of mixing valves that mix hot and cold water to achieve a desired water temperature. They also prevent very hot water from scalding your skin.
Thermostatic Cartridges
Anatomy of Ceramic Disk Cartridge
Splines and Points
The metal stem at the top of cartridges has ridges called splines. The ridges fit into the corresponding grooves within a handle. The ridges of a cartridge stem must match the grooves of a handle, so they fit together. If they are mismatched, they will not fit together.
The splines are measured in points. Each ridge or spline is one point. For example, a 16-point cartridge has 16 splines (ridges or grooves).
Hot Versus Cold Cartridges
A hot ceramic disk cartridge is the same as a cold ceramic disk cartridge, except that it opens in the opposite direction.
A hot cartridge opens or turns on the water by moving in the counter-clockwise direction. A cold cartridge opens or turns on the water by moving in the clockwise direction.
1/2" Versus 3/4" 20 Point Cartridge
16 Point Versus 20 Point Cartridges
Two types of quarter-turn ceramic disk cartridges are very common: 16 point cartridge and 20 point cartridge. These differ in the shape, size, and number of ridges or grooves or splines in the stem of the cartridge. These must be compatible with the number of splines in the faucet handle.
What Happens to Cartridges Over Time?
A cartridge is like a spark plug of a car engine. It lasts years but eventually needs to be changed.
Over time, faucet cartridges experience wear and tear, corrosion, and become coated with mineral deposits. This results in improper functioning such as water leaks and difficulty in turning the handles.
New Cartridge
Used Cartridges
New Thermostatic Cartridge
Used Thermostatic Cartridge
Common Indicators That You Should Replace a Hot or Cold Volume Control Cartridge
If your faucet is more than several years old and you are experiencing any of the following symptoms, you most likely need to replace one or both of the cartridges.
- Water leaks when handle is in off position
- Faucet handle is difficult to turn
Should You Replace One Cartridge or Both the Hot and Cold Cartridges?
If you need to replace either the hot or cold water cartridge for one of your faucets, we recommend that you replace both cartridges at the same time, because the other cartridge may also need to be replaced in the near future.
Faucet cartridges last years but eventually need to be changed, because over time they experience wear and tear, corrosion, and become coated with hard water mineral deposits. This results in improper functioning such as water leaks and difficulty in turning the handles.
Replacing both cartridges at the same time will save you time, money, labor cost, inconvenience, frustration, and hassle in the future. We offer a bundle of the hot and cold cartridges that costs less than buying both cartridges separately. Also, the bundle qualifies for free shipping, so you save even more.
Quarter Turn Ceramic Disk Cartridges
Common Indicators That You Should Replace a Thermostatic Cartridge
If you have a thermostatic shower system which is more than several years old and you are experiencing any of the following symptoms, you most likely need to replace the thermostatic mixing cartridge.
- Proper water temperature is not maintained
- Water temperature fluctuates while using shower
- Water is not hot enough (turning the water temperature lever to maximum does not yield hotter water)
Thermostatic Cartridges
How to Replace Cartridges
Highly recommended tool: 17mm socket with long handle.
Highly recommended tool: 17mm socket with long handle.
Highly recommended tool: 17mm socket with long handle.