Master thermostatic mixing valves are typically...

Master thermostatic mixing valves are designed to control the temperature of water supplied throughout a plumbing system, ensuring that the water delivered to various points of use is at a safe and comfortable temperature. By being installed just downstream of central water heaters, these valves effectively mix hot water with cold water, reducing the high temperature of hot water to a level that prevents scalding while still providing adequate supply for various uses throughout the building.

This configuration benefits the entire plumbing system by promoting safety and efficiency, as users can access water that is heated to an appropriate temperature without the risk of burns, making it an essential component in modern plumbing design.

In contrast, alternatives like locating them in the basement would not be ideal for their primary function, nor is their role linked to cooling systems, which typically deal with temperature regulation in HVAC applications. Additionally, while they are indeed beneficial in commercial installations, their utility extends to residential settings as well, making it incorrect to state that they are used only in commercial contexts. Thus, the answer highlighting their installation just downstream of central water heaters accurately reflects their main role in plumbing systems.