Most showers today have two types of valves: one is used for controlling temperature, and the second one is for controlling water direction. Let’s take a closer look.
Temperature Regulating Valves
In general, showers are easy to install. However, they share a water source with other appliances in the house. This causes temperature fluctuations when someone flushes the toilet or opens the tap. This has brought to light the need for temperature-regulating valves. There are different types available.
Mechanical or Pressure-Balancing Valves
Also known as anti-scald valves, mechanical valves use the difference in pressure caused by the sudden change in temperature. After turning the water on and arriving at the desired temperature, the system will work to maintain this level. If someone uses the faucet or toilet, there will be a sudden drop or rise in temperature, which will trigger a pressure change in the valve. The valve will shift and bring back the pressure to normal, preventing any scalding and temperature-related accidents in the shower.
This only works by adjusting the pressure, not the temperature directly. This means that it’s possible for water flow to decrease or increase if other appliances use up water. These types aren’t recommended if you are fixing up an older home. Any corrosion in the house’s structure can affect the valve’s efficiency. This is also why it’s wise to pressure-test pipes before installing the valves.
Thermostatic valves are a bit costlier than mechanical ones. These are equipped to control both temperature and pressure. By using this type of valve, you get the ability to preset the temperature of water before even turning the water on. This lets you hop in the shower without having to wait for water to heat up.
Traditional Mixing Valves
The final type of temperature-regulating valves is the traditional mixing valve. As its name suggests, it has the basic function of drawing water from both cold and hot taps and delivering the mixed water into the showerhead. There is some variation in control systems, depending on the shower unit and manufacturer. Some come with central knobs which divert water from the bathtub faucet. Others use a single knob, particularly for standalone showers.
Mixing valves aren’t as popular today as other types. They can be seen in older homes. The reason for their diminishing fame is the risk they pose when it comes to temperature regulation. Sudden changes aren’t as well-controlled as you’d want. This creates a risk for scalding or getting freezing cold water when someone uses the sink or flushes the loo elsewhere in the house.
Diverters and Transfer Valves
The second type of valves that we need for our showers to work properly control the flow of water. If you are using anything that’s beyond the simple shower setup, you’ll have to use a diverter to direct (and redirect) the water flow between components. These do not control the temperature, only flow direction. Hence, they must be used in conjunction with a temperature-regulating valve.
Basically, tee diverters are the most popular and common type. They have a simple pull arm placed on the tab. When water reaches your desired temperature, pull the arm up, blocking the tap and directing water to the shower. Three-valve diverters are another variation, allowing you to adjust cold and hot water separately. By turning a knob, you divert water from tap and shower. The 2-valve diverter, on the other hand, uses one rotating control for both hot and cold water, and a second controller for diverting water from shower and tub.
Diverter valves divert the flow of water from a shower to a tub, and vice versa. Meanwhile, transfer valves let the water flow to different outlets simultaneously. If you have shower walls, this type is ideal. This can also be beneficial if you prefer using a handheld showerhead without turning off the main showerhead.
These valves let you use 1 to 2 components at a time in general. There are a few that allow for more than 2 components. These setups activate either one or a combination of two components, but never all three components at the same time.