Having a well-operating commercial HVAC system can create a comfortable environment, make the building stay cool in summer and warm in the winter. Understanding the commercial HVAC System will help you keep the system working properly and bring effective performance. This article will provide you with important details regarding the operation of commercial HVAC systems and the various types of commercial systems.

1. What is a Commercial HVAC system?

The purpose of a commercial HVAC system is the same as a residential HVAC system: to keep building occupants comfortable with high-quality air in an environment where the humidity is between 40 and 60 percent and the temperature is 72 degrees.

Burning fuel is a common method for heating air (gas, oil, electricity). The method of cooling the air is the reverse (naturally), and it involves drawing hot indoor air out and cooling it using refrigerant or water-cooled devices while also removing additional humidity.

Fans are employed in ventilation systems to enter the required outside air, filter both the external and recycled internal air, and exhaust the polluted air from the building. As a result, the CO2 stays below 1 million molecules per liter.

A good ventilation system can eliminate smells, dilute gasses (such carbon dioxide), and stop the spread of respiratory illnesses. Without it, undesirable particles would cause the air to get stale and would promote the growth of mold and mildew.

Commercial HVAC System
Commercial HVAC System

2. How Does a Commercial HVAC System Work?

Three elements needed to regulate the climate of a business building include: warm or cool air, a distribution system, and controls.

2.1. Warm or Cool air

When the heating in a commercial HVAC system is turned on, the burners typically produce combustion gas that is delivered to a heat exchanger, where it heats the air passing through. Heat pumps occasionally bring outside heat inside. Similar to heat pumps, but operating in reverse, air conditioners move indoor heat outside.

Hot water is transported through pipes installed in the walls, floors, or ceilings of certain commercial buildings using a boiler system to heat the water. Although you might not notice the building itself warming, you will sense the air warming.

2.2. Distribution

Check it out – mechanical systems use ventilation to move the air within a building, and the principle that warm air rises and cool air falls is helpful. There is a continuous induction and evacuation of air, some of which has undergone thermal modification.

2.3. Controls

To control the HVAC systems, commercial buildings can use simple, programmable thermostats that transmit different heating or cooling queues throughout the day, similar to residential HVAC systems.

Direct digital controls (DDC), which are more complicated, can also be used with commercial HVAC systems. Modern controls improve energy efficiency and dependability in commercial buildings. To monitor and manage temperature schedules and even lighting operations, a central computer makes use of sensors.

Users have access to performance updates, troubleshooting, and maintenance via a primary workstation where staff may manually respond to and change the settings. The DDC costs more than the other options because of its complexity and versatility.

Both simple controls and DDC allow users to use temperature setbacks to conserve energy, ranging from 5% to 20%. Temperature setbacks are times built into the thermostat when neither heating nor cooling is required, such as after a workday is done and no one is in the building.

Commercial HVAC Systems
Commercial HVAC systems are needed to regulate the climate of a business building

>> Read more: Difference Between Residential and Commercial HVAC

3. Commercial HVAC system types

3.1. Single-Split System

Split Systems are frequently connected to the ductwork of a building, the same way as in a residential unit. They perform well for smaller commercial structures such tiny offices, restaurants, or stores since they are excellent for residential buildings. Each area may be controlled by using a thermostat or DDC.

Pros: 

  • Installing them is less expensive, making them perfect for small commercial areas.
  • Each unit is self-sufficient. As a result, even if one malfunctions, the others will still function.
  • Energy-efficient. Only the room that requires cooling can receive air conditioning from each indoor unit.
  • The ideal option for a single room that needs an additional HVAC system

Cons: It occupies a lot of space as it has an outdoor unit for each internal unit

3.2. Multi-Split System

Multiple interior units can be connected to a single outdoor unit using multi-split systems. Larger areas like retail stores, medical offices, and restaurants are often where these systems are deployed.

A multi-split system requires expert installation and includes a lot of pipes. Hire a contractor to complete the work since poor installation might lower your HVAC performance by 30%.

Pros: 

  • Less space needed. One outdoor unit can be used with multiple indoor units.
  • It maintains your building’s exterior attractiveness.
  • The building doesn’t need to have ducting for the installation.

Cons: 

  • The price of installation is higher.
  • Because there is more pipework to be done, installation may take longer.

3.3. VRV or VRF System

A heat pump that uses refrigerant in the heating and cooling lines is called a variable refrigerant flow (VRF) or variable refrigerant volume (VRV) system. A single condensing unit is connected to several evaporators.

Pros: 

  • Ideal for big and medium-sized business settings
  • Simple to install in expanding buildings
  • Quick installation without disrupting building inhabitants

Cons:

  • Installation is expensive
  • The whole HVAC system will be affected if the unit breaks down

3.4. CAV and VAV Systems

Variable air volume (VAV) or constant air volume (CAV) systems employ a single-duct supply and return arrangement with fluctuating airflow (VAV) or constant airflow (CAV), to maintain temperatures at predetermined levels.

commercial hvac system types
Example of a simple variable geometry VAV system – Source: AirLink 

VAV System

CAV System
Pros
  • Cut back on energy costs
  • Suitable for structures with a range of ventilation needs
  • Superior humidity and temperature control
  • Suitable for spaces that have constant ventilation requirements
Cons
  • Costly to set up
  • The system requires a large space because a fan room must be installed inside the structure.
  • Produces fixed air volume, resulting in high energy expenditures in areas with modest airflow requirements.
  • Poor at controlling humidity

4. How long do commercial HVAC systems last

A business HVAC system will typically endure between 10 and 15 years. This indicates that you may increase the overall system life by roughly 33% by adhering to best practices and working with maintenance and efficiency specialists. Even though there are a variety of elements that affect lifespan, they can all be improved.

>> Read more: Common Commercial HVAC Problems and How to Fix