What is radiant heating? A radiant heating system is usually installed in the floor and uses radiant heat properties to heat the home with better energy efficiency than a furnace. In order to better understand...
In order to better understand radiant heating, let's take a moment to talk about thermal energy and heat transfer first. Thermal energy is just another way to say "heat." Thermal energy always moves from warmer to cooler materials. There are three ways for this heat transfer to occur. First is convection, which is when you blow it around - like blowing heat through ductwork. Second is conduction, which is when a warm surface touches a cooler surface and warms the cooler surface. And third is radiant where energy is transmitted as an infrared wave from one surface to another without really losing any heat in the transfer. Radiant energy is how our planet is heated by the sun. Space is really cold, but we get plenty of heat from the sun and that is how we get it. So, radiant heating is a way of using radiant energy to heat as opposed to conduction or convection, and the way you do that is by turning a surface into a heating panel which radiates energy into the room. The logical choice for a heating panel is the floor because the heated air from that floor rises and spreads throughout the room. So, radiant heating is when you turn a surface into a heating panel and use that to heat a space.
A hydronic heating system has three major components. There is a heat source that can be a furnace, a boiler, a hot water heater, a heat pump, some times even solar panels, anything that is going to generate a significant amount of heat. Then there is a control system and that is how the heat is distributed to different parts of the house. On a radiant heating system, you can actually turn different zones on and off depending on when a thermostat is calling for heat. Then the piping system flows from the control system and actually sits in the heating panel, (normally your floor,) and provides heat that way. For example - A typical heating cycle today in my house would operate as follows: The thermostat in the master bedroom comes on, that opens the valve in the control system and allows hot water to flow to that set of pipes and warms the floor to warm the room. Once the thermostat is satisfied, it shuts off. If the heat source needs to provide additional BTUs throughout that cycle, it just comes on and heats up its tank of water to a certain temperature and shuts off when it is done.
