A hydronic baseboard heater is a component of a home heating system; it combines resistance heating technology as well as boiler technology. Furnaces which use fuel to heat air directly are very different than hydronics which rely on a fuel to heat liquid which in turn heats the space. In most cases the modern system uses electricity as the fuel; many years ago the liquid was heated in a traditional boiler using an open flame to heat water. Depending on the type of system that is being installed, the liquid medium can be water, oil or liquid silicone; in some cases a refrigerant is used. Regardless of the liquid, it is sealed in the system and unless there is a leak in one of the pipes, never has to be recharged.
When the system is installed centrally, the hydronic baseboard heater is connected directly to a central boiler where the medium is heated. In many cases the heat source is electric; it passes through a coil which heats up and then heats the water. The hot liquid travels throughout the home through a series of baseboard heaters. As the heated liquid reaches a heater unit, cool air is drawn from within the space, it travels over the heated pipes and becomes heated as well.
A hydronic baseboard heater can also be self contained; these types are most popular when the installation is being done as a retrofit after the home has been constructed. The units are each connected to the electrical system, when the unit is turned on electricity heats the fluid contained inside. The heat is radiated into the space as the liquid continuous to heat up, the same as the old time radiator. What is great about these units is the way in which they hold heat. Once the liquid has reached the point where it has heated the room to the desired temperature, the power supply is cut by the thermostat. It takes a considerable amount of time before the power has to come back on because the liquid cools slowly.
As there is no fossil fuel involved in generating the heat, there is no need to install any form of ventilation; this in itself is a major benefit to the homeowner who wants to use this system, either fixed or portable.
