hvac roof

What does HVAC stand for?

HVAC stands for Heating, Ventilation and Air Conditioning, which describe the functions of an HVAC system. HVAC systems can be found in just about every building in the world, from your house or apartment to the classrooms and labs on campus. In this blog post we will dive into how these systems work in general, and what they do on campus. 


Main Functions

The main function of an HVAC system in a building or home is to maintain a comfortable environment for the occupants.  It controls the temperature by heating and cooling the room, and can control the humidity level, and also ventilates a space by distributing air within the room. 

thermostatHVAC systems are controlled by a thermostat, a sensor that measures air temperature in a room and allows for the system to control to a specified temperature (called a setpoint).  Any time the temperature of the room deviates enough from the thermostat setpoints, it triggers the HVAC system to heat or cool the room.


Common Misunderstandings

1. When my HVAC system is circulating air, it is always heating or cooling.  One of the biggest jobs of HVAC systems is the V for Ventilation. When you hear the systems turn on, and feel air blowing on you, it may just be circulating air through the space without heating or cooling it. Ventilation is important to bring in outside air, which helps control the temperature and humidity levels and pump clean, fresh air into buildings to dilute allergens, bacteria, mold or smells. 

2. Leaving your HVAC system on is always a waste of energy.  Even with the system left on, it can be programmed to "sleep" and turn down or off until it is needed. We do this for our Holiday Building Shutdowns and it avoids running them unnecessarily. Turning it off will always save energy, but if the setpoints are adjusted properly, a "sleeping" system can save just as much energy.  

3. The HVAC system controls the temperature just for you. Yes, it is for you, but it is also for the other 100 people in the building or the other 6 rooms in your house. HVAC systems on campus are set up to serve "zones" within the building and typically an entire zone (often 3-5 offices, or sometime an entire floor) will be controlled to a single temperature. The system is for everyone, therefore if you change it to suit your needs, you change it  everyone else in your zone as well. 


TherMOOstat and HVAC

How does TherMOOstat connect to HVAC? It isn't directly connected yet. For now, TherMOOstat, a self-report tool used on the UC Davis campus to gauge occupant comfort in buildings,  gives us insight into how well the HVAC systems are working in buildings on campus. 


We crowdsource comfort information using TherMOOstat, in order to understand how we need to change the HVAC settings for a more comfortable and energy efficient future.  YourTherMOOstat submission won't change the temperature instantaneously but will help in the future. The more feedback you send us, the better we will be able to help you.