Do you know how air conditioning, or HVAC, systems work? The HVAC system is composed of Heating, Ventilation, and Air Conditioning (HVAC). It is used to condition the indoor environment of a building to maintain a comfortable temperature for its occupants. A hydronic HVAC system utilizes water as the primary fluid to transfer energy throughout the building. Water has outstanding heat transfer characteristics, along with other benefits (i.e. – plentiful, non-toxic, “green," inexpensive) that make it ideal for this purpose.
In order for the system to provide heat, a heat source, such as a boiler, must be present, and for cooling, a cooling source, such as a chiller or cooling tower, must be present. The heated or cooled water is pumped throughout the building to air handling units or terminal units (or other similar), where it transfers energy with air from the ventilation system before it recirculates to the heating or cooling source. The conditioned air is then delivered to the room.
The above description oversimplifies hydronic HVAC systems since they come in many variations, such as geothermal heat pumps, radiant systems, fan coils, VAVs, four-pipes, two-pipes, etc. Just to give you a basic understanding, I would like to use an analogy, if I may.
Imagine a large building (such as a school) is like the human body. It has different parts that must be heated or cooled (hot head, cold feet, etc.). The water in the HVAC system is similar to the blood in your body – it is the component that transports energy from one area to another. Water is circulated with pumps, just as the heart circulates blood. Without circulation, the system dies! The boiler (stomach or digestive system) converts fuel (food) such as natural gas into energy. The air handling system (lungs, or respiratory system) provides proper fresh air and ventilation. I could carry the analogy further, but does this help paint the picture?
Buildings can therefore be viewed as large bodies with mechanical systems designed to keep "human" bodies comfortable. Hoffman Hydronics considers itself like a "medical specialist", someone you turn to if you need a high level of knowledge about a particular field. For us, that field includes the application of equipment related to the heating, cooling, or circulation of water in a Hydronic HVAC system.
In a nutshell, that's how a hydronic HVAC system works. Stay tuned for more general knowledge posts!