Hydronic systems can use a variety of energy sources to heat the water: a gas water heater, electric boiler, wood boiler, heat pump, solar collector, or even geothermal energy.
Baseboard and Radiator Heating
Baseboard hot water heating and radiators for space heating have been used in American homes for many years. These heating systems use hot water from a boiler that circulates into a system of pipes and then through baseboard heating units or into radiators located throughout the house.
Radiant heating systems circulate hot water from your boiler through durable tubing installed in or under your floors, walls or ceilings. This form of heating also can be installed outside your home under your sidewalks and driveway to deliver warm water that melts ice and snow. It also can be installed to warm a swimming pool or whirlpool.
Radiant heating is distinct because it warms people and objects that come in contact with it rather than just heating the air. When installed under foot, the tubing carrying the hot water is usually encased in a slab of concrete or lighter-weight gypsum cement. In some cases, the tubing can be fastened to the underside of subflooring instead. The heated water warms floors to about 85 degrees Fahrenheit or cooler (it generally feels similar to a tile floor warmed by direct sunlight). A zone control adjusts floors of various rooms to the desired temperatures.
Indirect-Fired Water Heater
The consumable hot water provided by an indirect-fired water heater is heated by hot water that is generated by the home’s boiler and circulated through looped tubing from the boiler into the water heater. The heat from the water in the tubing is transferred to the water inside the water heater and then it flows back through the tubing to the boiler and the cycle continues.