In a hydronic system, what medium is primarily used for heat transfer?

In a hydronic system, the primary medium used for heat transfer is liquid, typically hot or cold water. This type of heating (or cooling) system is designed to circulate water through pipes to transfer heat throughout a space. The water serves as an efficient medium because it has a high specific heat capacity, meaning it can absorb and carry significant amounts of heat energy without a drastic change in temperature.

Using water as a medium in hydronic systems allows for effective temperature control and distribution, providing comfortable heating or cooling within buildings. The reliance on water also means that these systems can be designed to work with various heat sources, such as boilers or heat pumps, enhancing their versatility and efficiency in building climate control.