Steam and Hot-Water Baseboard Heaters
Baseboard heaters are designed to be installed along the bottom of walls where they replace sections of the conventional baseboard (see Figure 2-43). Locating them beneath windows or along exterior walls is a particularly effective method of eliminating cold drafts.
Baseboard heaters are frequently used in steam and hot-water heating systems (see Figures 2-44 and 2-45). In a series-loop sys- tem, supply and branch piping can be eliminated by using the base- board heater to replace sections of the piping. In other words, there is no need for supply and return branches between the baseboard heater and the mains.
Baseboard heaters are also available with electric heating elements controlled by a centrally located wall-mounted thermostat or a built-in thermostat. Each unit is actually a separate heater (see Electric Baseboard Heaters in this chapter), but they can be joined and wired together to form a baseboard heating system.
The Institute of Boiler and Radiator Manufacturers (IBRM) has established testing and rating methods of baseboard heat-emitting units. The output for baseboard units is rated in Btu per hour per linear foot.