Modern HVAC systems are more complex than many people might expect. They rely on computerized systems called programmable logic controllers (PLCs) to respond to changing temperatures and keep the temperature inside a building at a comfortable level. Whereas older HVAC systems relied simply on a thermostat that would turn the unit on and off, PLCs used in modern “smart” thermostats offer more precise control and allow HVAC systems to operate more efficiently. One of the key things taught at HVAC school today is how these systems work and how they can benefit businesses and homeowners.
How Does a “Smart” Thermostat Work?
PLCs do far more than just enable and disable the HVAC system itself. They can control the temperature, humidity, air pressure and airflow through the HVAC system. This gives users more granular control over zoning, energy use and home comfort.
A PLC achieves this by having several systems working in tandem:
- Thermostat: The thermostat senses the temperature in a particular zone, so the HVAC knows whether to heat or cool a room or to switch off for now.
- Other sensors: The PLC can also sense humidity, carbon dioxide and occupancy, so it can make decisions about the perceived comfort level of the room. Humid conditions, for example, can require more cooling than dry conditions.
- Dampers: These systems control the airflow through the system. For traditional central air units, dampers are very important, as they can limit and control the flow of air to different rooms or areas of the property. Ductless mini split systems with separate air handlers also offer good control over air flow.
- User Interface: Smartphone apps, remotes, and wall-mounted keypads with LCD displays give users a high degree of control over their HVAC systems, such as setting up schedules for adjusting the temperature depending on the time of day.
How Smart Technology is Changing the World of HVAC
“Smart” systems have added a new degree of technical sophistication to HVAC jobs. Historically, HVAC technicians focused on refrigerants and the mechanical aspects of HVAC maintenance. Today, they’re also expected to understand the workings of complex electronics. If you’re considering a career in the world of heating and cooling, look for an HVAC school that can teach you about smart technologies.
Today’s HVAC technicians need to be tech-literate, with a good working understanding of how PLCs and “smart” climate control systems operate. Being confident in these technologies will help you not only explain the benefits of a smart HVAC system to clients but also troubleshoot them.
Enroll in HVAC School Today to Start a New Rewarding Career
AT ETI Campus, we offer comprehensive training for prospective HVAC technicians. Our HVAC/R training program provides you with both the theoretical and hands-on knowledge required to become a successful HVAC technician. We’ll teach you everything you need to know to start work in the HVAC industry, and offer employment advice so you can hit the ground running once you graduate.
To learn more about our HVAC school, contact us online or explore our HVAC/R program page to see detailed information about the course and how to enroll.
Key Takeaways
What is a PLC in HVAC?
A programmable logic controller (PLC) is a computerized system used in modern HVAC systems to control temperature, humidity, airflow, and overall system efficiency more precisely than traditional thermostats.
How do PLCs improve HVAC systems?
PLCs use sensors, thermostats, dampers, and user interfaces to monitor conditions like temperature, humidity, and occupancy, allowing for better energy efficiency, zoning, and comfort control.
Why are PLCs important for HVAC technicians?
Modern HVAC technicians must understand PLCs and smart systems to install, troubleshoot, and explain advanced climate control technologies to clients.
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