Home Improvement

What Is an Air Handling Unit? AHUs Explained

Male technician repairing air conditioner outdoors

Spending on home improvement projects reached $420 billion last year. Homes have a lot of systems that work together to make them habitable and comfortable. An HVAC system is one the most important of these.

An air handling unit is central to the tasks of cleaning the air and adjusting its temperature. If you are interested in HVAC engineering or how an air conditioning unit works, it’s important to start at the basics. 

Read on to learn about the makeup and functions of an air handling unit, the various types of handlers, and the different parts that make up an air conditioning unit. 

Air Handling Unit Basics

The purpose of an air handling unit (AHU) is to take air from outside or recycle air from the building, clean it, heat or cool it, then send it back out. Unless you live in a colder region and only have a furnace, most HVAC systems have an air handler.

You must have the proper size AHU to work with your heat pump. Doing so will increase your Seasonal Energy Efficiency Ratio (SEER), or how productive your system works relative to your house. 

AHUs are common in medium or large industrial or commercial buildings and generally located in the basement or the roof. Traditionally, even bigger buildings would have one large AHU. Now, it is much more common to see two or more AHUs that handle different zones.

AHU Makeup

Most air handlers are large metal boxes that contain heating and cooling elements, filters, dampers, sound attenuators, and a blower. A duct system connects the AHU to different segments of the building, allowing it to distribute and return air to the HVAC unit.

Handlers use coils to heat and cool air. A blower in the machine then sends the air back out into the building.

Dampers are sheets of metal that can seal off ductwork in various places. You also can adjust them to allow different amounts of air to enter or exit. Filters remove dirt and debris from the air.

Sound attenuators act as a muffler for the ductwork, reducing the transmission of noise from the AHU. In dryer climates, some air handlers will have humidifiers. These use sensors to detect low humidity in the air and make adjustments.

Types of Air Handlers

There are three main types of AHUs. Terminal units are the simplest design. They contain only a coil, blower, and air filter. They are sometimes called a fan coil or blower coil.

Makeup air units are larger handlers that condition air from the outside, instead of using recycled air. Rooftop units are large air handlers designed for outdoor use.

The complexity of installing an air handler depends on the size of your home or building and the type of unit you require. A reputable installation company will be able to tell you which type of handler is best. Having the right unit that is installed correctly will help optimize efficiency and lower heating and cooling costs.

Learn More About HVAC Systems

Now that you know what an air handling unit is and how it works, you can better understand the inner workings of your HVAC system. If you suspect problems with the AHU, be sure to contact a reputable HVAC services company for repair or installation. 

We hope you found this information about the inner workings of an air conditioning system useful. If so, be sure to check out some of our other home improvement posts, as well as those on business, finance, health, travel, and many other topics.