If you’ve ever headed to the local shops to escape a scorching summer’s day, then you have commercial HVAC to thank.

The commercial spaces we use everyday are kept comfortable by complex HVAC systems. These machines heat and cool our offices, shops, hospitals, schools and most other publicly-accessible spaces.

We’ve developed a range of technologies that make this possible. They vary greatly in complexity. Some of them are similar to the air conditioning in your home. Other systems use advanced technologies that you may not have come across before.
In this article, we’ll explore how commercial HVAC systems work, how they keep us comfortable, and some of the common problems we deal with.

What is Commercial HVAC?

Commercial Heating, Ventilation and Air Conditioning (HVAC) is a family of large-scale climate control systems used in commercial and industrial settings.

Commercial HVAC systems have four main responsibilities:

  1. Cooling and heating the air inside of a commercial building
  2. Maintaining comfortable humidity levels
  3. Introducing fresh air from the exterior of a building
  4. Extracting contaminated air to keep harmful gases at an acceptable level

These functions are crucial to commercial operations. Maintaining a comfortable indoor temperature has been shown to increase productivity in offices, improve sales in retail settings, and impact our general mood.

How Does a Commercial HVAC System Work?

Commercial HVAC systems function similarly to the air conditioning and heating in your home. They work on a much larger scale, but they use familiar technologies to heat, cool and ventilate commercial spaces:

1. Heating

Heating is achieved by burning a fuel source (e.g. gas). Cool air is then passed over a warm heat exchanger, before it’s distributed throughout the building using ductwork.

In modern HVAC systems, it’s common to use heat pump technology to provide energy-efficient heating. Heat pumps work similarly to air conditioning, except they absorb warmth from outside the building, and use it to heat the indoor spaces.

2. Cooling

Cooling is provided by conventional air conditioning technology. In this case, warm air is drawn up into the system and passed over coils that contain refrigerant. The refrigerant absorbs heat from the air, and the cooled air is then distributed back into the building.

3. Ventilation

Finally, HVAC systems provide ventilation using fans that draw in air from outside the building. Outside air is filtered to remove pollution and contaminants before it’s distributed into the building.

Ventilation is one of the most important functions of HVAC systems. Commercial buildings are often well-sealed, and there can be thousands of people inside. This has the potential to cause buildups of harmful gases such as carbon monoxide. By ventilating the space, HVAC systems are able to provide clean air that’s safe to breathe.

HVAC units on the roof

The Major Types of Commercial HVAC Systems

There are dozens of variants of commercial HVAC technology. Because HVAC is a major consumer of energy, manufacturers are continually improving the efficiency of their designs.

Despite the variations in the technologies used, commercial HVAC systems are usually delivered in one of three ways:

1. Individual

Individual systems (also called “decentralised” systems) use multiple units to deliver heating, cooling and ventilation. Think of an office building where each individual room has its own air conditioner.

These types of systems are flexible and easy to control, but they don’t scale well, so they are uncommon in larger commercial buildings.

2. Packaged

Packaged HVAC systems combine the air conditioner, heating system, evaporator and fan coil into a single unit. These systems are compact and powerful, so they are ideal for buildings that are short on space.

Packaged HVAC is often mounted on the roof of commercial buildings, where they’re known as Rooftop Units (RTUs). RTUs and packaged HVAC systems typically need more frequent maintenance than other types of commercial HVAC.

3. Centralised

A centralised HVAC system is a single unit that supplies the HVAC needs for an entire building (or a particular zone within the building). These systems are common in larger commercial spaces.

They’re a powerful and flexible option, and centralised systems are often more energy efficient than the alternatives. Some types of centralised HVAC require extensive ductwork, but technologies like Variable Refrigerant Flow (VRF) can eliminate the need for air distribution systems.

a man repairing a hvac system with specialised equipment

Common Problems With Commercial HVAC

Commercial HVAC systems work hard. They often run 24 hours a day, and they’re responsible for heating and cooling very large spaces. This means they need regular maintenance to prevent breakdowns.

Some of the most common problems we encounter with commercial HVAC systems include:

  • Dirty filters – All the air handled by your HVAC system is passed through filters. Filters should be changed on a monthly basis. Clogged filters can dramatically reduce the cooling power and energy-efficiency of the system.
  • Dirty condenser coils – The condenser coil is responsible for disposing of excess heat that’s extracted from inside the building. Dirty coils are far less effective, which can lead to a reduction in cooling power.
  • Frequent cycling – The compressor in a HVAC unit should run on a consistent cycle, turning itself on and off as necessary. If the compressor is cycling on and off too frequently, it can be a sign of problems like dirty filters, faulty thermostats and low refrigerant levels.
  • Refrigerant leaks – Commercial HVAC systems are prone to refrigerant leaks. Leaking refrigerant will cause the system to stop blowing cool air. Any refrigerant leaks need to be addressed by a licensed technician as soon as possible.
  • Blocked drains – Air conditioning naturally collects moisture from the air. When the condensate drain becomes blocked, your HVAC may smell stale or mouldy, and it can lead to water damage inside the building.
  • Strange noises – Your system may contain hundreds of moving parts. Noises like squealing, rattling, buzzing or hissing are a good sign of a major problem. Make sure you have any unusual noises investigated by a commercial HVAC technician as soon as possible.


Keep Customers Happy With Commercial HVAC Maintenance by the Air Conditioning Doctor!

You may not think about it very often, but commercial HVAC systems are an important part of our everyday lives. These powerful appliances work hard to keep us comfortable, and that means they need regular maintenance to ensure they’re always online.

The Air Conditioning Doctor is a qualified commercial air conditioning and refrigeration technician. Our team is licensed to work on a broad variety of commercial HVAC technologies, providing maintenance, servicing, repairs and installation.

We offer a regular Maintenance Program that’s designed to maximise the uptime of your commercial HVAC system. As part of our program, we’ll regularly visit your property to inspect, maintain and test your equipment, which helps protect against unexpected breakdowns.

Contact us for a tailored quote on maintenance and servicing for your commercial HVAC equipment!