Now let us try to understand as in how does hydronic heaters work. A hydronic heater uses a boiler to heat the water and baseboard convectors that is located in each room which helps in the distribution of heat. A centrally located thermostat in a hydronic heater controls the desired air temperature. When heat is required, the boiler starts heating the water that is in turn circulated through pipes to baseboard convectors. As a result the baseboard and the surrounding air is warmed as the hot air circulates through the baseboard and the heated air is distributed to the room through the process of convection. However houses which are big or has multiple rooms, the house is zoned with several thermostats that control the temperature in each of the zone.
There are some hydronic systems that uses piping in the ceiling or on the floor to heat the surrounding surfaces in the various rooms and are known as radiant heating systems because they radiate heat to the room. Heated water is circulated through the pipe and it in turn warms the floor or the ceiling.
At this juncture it is important to understand as to why transfer of heat through hydronic heater is so effective. This is mainly because of the way in which transfer of heat takes place. Transfer of heat in hydronic heating systems takes place in three ways. They are conduction, convection and radiation.