Whether you are talking about your home or business, there is often confusion surrounding the term HVAC. For example, you may have wondered about the difference between AC and HVAC or if there is any overlap between the two.
In general, HVAC denotes a complete system that includes heating, cooling, and ventilation, while AC refers only to the cooling portion. Here we address some of the more confusing aspects of the two terms to help you understand them better.
What Is AC?
AC is a common abbreviation for air conditioning or an air conditioner. It denotes a specific type of cooling system that is designed to improve comfort in interior spaces.
Even though AC units use refrigerants, air conditioning only applies in habitable spaces and should not be confused with refrigeration. Let’s explore a little more about air conditioning systems before asking: Is AC same as HVAC?
Types of AC Units
There are several common types of air conditioning units. Some of the most popular include:
- Central air conditioning — A central air conditioning system works to cool an entire house or building from a central location. They typically pass air over pipes filled with refrigerant, which cools it. The cooled air is then moved through ductwork to cool individual spaces. A thermostat generally controls these systems. When comparing AC vs HVAC, central air is the most common cause of confusion.
- Room air conditioners — Most commonly mounted in windows, room AC units can also be installed through a wall. They are self-contained systems that work by plugging them into a standard (110 or 220 volt) household outlet. Some room air conditioners can cool large rooms, but most are designed to cool smaller spaces.
- Portable air conditioners — Some people opt to use a portable air conditioner when installation or direct ventilation to the outside is not possible. These are generally designed for single-room use and can be moved from one location to another.
What Is HVAC?
HVAC is commonly used as shorthand for heating, ventilation, and air conditioning. It indicates a complete heating, cooling, and moisture ventilation system that conditions interior air to make it safer and more comfortable. HVAC systems utilize ductwork to deliver conditioned air throughout an interior space and to remove moisture from the building. In doing so, they create comfortable, climate-controlled indoor spaces while also highlighting the key difference between AC and HVAC systems.
Recommended: HVAC License Requirements: State-by-State Directory
What Is an HVAC System?
An HVAC system includes all of the components necessary to heat, cool, filter, and otherwise condition the indoor air of a building. These components can vary depending on the type and complexity of your system, but they generally include:
- Heating unit
- Air conditioner
- Air filters
- Vents and ductwork
How Does an HVAC System Work?
There are many different types of HVAC systems, but they all operate in the same basic way. First, they draw air in from an external source, such as outside the home. This air is filtered to remove impurities that could cause problems within the unit. Once filtered, it is conditioned to the appropriate temperature and humidity level and dispersed throughout the home.
If it is being cooled, the air is generally passed over refrigerant-filled coils. A furnace traditionally does the heating component, although other methods are becoming more popular. For example, heat pumps use refrigerant-filled could for heating and cooling. Natural gas, electricity, and oil are popular fuel sources for heating systems.
Existing air is vented outside as this fresh, conditioned air is sent into rooms. Ventilation is an important part of any HVAC system. It removes impurities so that air is safe to breathe and is also less likely to cause damage to sensitive heating and cooling units.
Does HVAC include heating and cooling?
HVAC always includes heating and cooling, which is the biggest difference between AC and HVAC. Additionally, they remove excess humidity to help improve indoor air quality, and some systems also include air filtration and purification systems.
Considering the complex nature of HVAC systems, it should be no surprise that questions about them — and air conditioning and heating units — are pretty common. Here are our answers to a few of the questions we often get.
Is the AC and Heater the Same Unit?
Whether your heater and AC are the same unit depends on the system you have installed. Some systems use a central air handler for both functions, while others rely on completely separate components. For example, you may have a gas furnace that uses hot water to heat your home while having a separate central air conditioning unit. Combined, these systems make up the HVAC system.
Heat pumps are growing in popularity and perform both heating and cooling functions. They work by moving heat from one place to another to warm or cool the air sent into your home. Mini-split systems are another all-in-one HVAC that does not require ductwork.
Does HVAC Mean Central Air?
Many people use the terms HVAC and AC interchangeably, but they are not the same things. As you have learned, the main difference between AC and HVAC is that HVAC is the entire system that includes heating, cooling, and ventilation, while AC only includes the cooling aspect.
Will All HVAC Features Break if the AC Breaks?
In many systems, a failure of the AC portion will not impact the rest of the unit’s operation. This is especially true in systems where the heat and air conditioning are handled separately. However, in some cases, AC failure must be addressed immediately to restore all operations.
Consider the ease of a heat pump compressor unit breaking. This must be used to draw outside air into the home, so it is critical to all unit functions. If the compressor breaks, you must schedule a repair immediately or stop using the system.
However, if you have a separate furnace, you should be able to continue running that in cold weather and put off AC repairs.
Wrap Up: the Difference Between AC and HVAC
Air conditioning systems cool interior air, removing excess moisture in the process. HVAC systems are more comprehensive and also include heating and ventilation units. There are many different types of AC and HVAC systems on the market, and most should be installed by a licensed HVAC professional.