What is an HVAC System?

What is HVAC?

An acronym for Heating, Ventilation and Air Conditioning, HVAC refers to systems in a home or building that produce safe, clean and comfortable air within a space.

•Heating: The "H" in HVAC stands for heating, and as one might guess, this system heats the air in your home. Generally, this may involve heating the space with forced hot air from the stove or radiant heat from the boiler in your home. In commercial buildings, heat may come from boilers, heat exchangers, and coils inside air processors.

• Ventilation: The "V" in HVAC stands for ventilation, which is replacing old, stale air and carbon monoxide with fresh air to improve indoor air quality. Manual ventilation will involve opening doors and Windows. Mechanical ventilation (HVAC) usually involves heating or air-conditioning units that draw fresh air into the system. The system cleans the air through filters, regulates its temperature and humidity, and exchanges it for stale air.

• Air conditioning: As important as the other two components of HVAC, air conditioning is about comfort and humidity control. The air-conditioning components of the HVAC take warm, moist air from the space and cool it. It also removes moisture from the air to control humidity.

How does the HVAC system work?

All three HVAC components work together as a system, with different components performing certain functions.

In the case of a home HVAC system, there is usually a central heating unit called a furnace. The furnace has a supply side that pushes air through the home through pipes, and a return side that pulls indoor air back into the system. When the system draws indoor air through reflux, the air then passes through the furnace, through the coils being heated, and back into the home via the blower.

HVAC systems also contain air conditioning, usually in the form of outdoor units placed outside the home. The unit contains a compressor that condenses refrigerant gas into a liquid and then pumps it through a system called a piping unit. The wires travel to coils in the home's existing plumbing system to cool the moving air. The system still relies on the furnace's blower to pull air through the return vent and push it through the ductwork.

In terms of ventilation, these systems work in several ways. Some have a simple set of blinds that homeowners can open and close. Others may have advanced components called HRVS (Heat recovery ventilation) systems. These systems draw in fresh air while allowing the outgoing air to heat or cool the fresh air. In any case, ventilation is to improve indoor air quality.

What's the difference between HVAC and air conditioning?

Although the two are closely related, there are subtle differences between HVAC and air conditioning. Air conditioning is just about cooling the space and controlling humidity. Hvac needs more.

All HVAC systems include air conditioning components, but not all air conditioning systems can be considered HVAC. If an air conditioning system does not require heating and ventilation, then it is just air conditioning. However, if there is a furnace and ventilation method, it becomes an HVAC system.

Think of it this way: Air conditioning is just one part of HVAC. Heating is just as important as ventilation.