HVAC Controls and How They Function

HVAC controls are components that help operate heating, ventilation, and air conditioning units in residences, businesses, and so many other structures and environments. Without these devices, people wouldn’t be comfortable in many regions of the world, food would spoil, and indoor environments would be polluted or toxic.

Control systems consist of a device that measures the quality or temperature of the atmosphere and compares that measurement with a desired target that has been pre-programmed by the user. A user could be a homeowner, a grocery store manager, a zookeeper, a business owner, or many other things. When that control device senses a difference between the environment and what is wanted, it sends a signal to special equipment to begin regulating the air.

Most HVAC controls have these central devices, and most of them are customized and programmable. A person may use a feature such as a timer or schedule to set various temperatures, ventilation, or humidity at certain times of day or night, such as with the commonly familiar household thermostat. An alarm may be set to alert members to dangerously high or low situations involving any number of environmental factors that could jeopardize the health or safety of anyone or anything contained in the area. Both digital and analog parts go into carrying signals to and from these HVAC controls. Digital pieces are used in dry components that help engage and disengage equipment while analog parts send electrical signals to help move water or air through motors or dampers.

Sometimes, more than one of these HVAC controls is used to complete a task, which forms something like a brain for the entire system. Without the brain, a fan won’t run at the right speed, and a valve can’t close at the right time. This sophisticated machine cannot be automated without all the parts making a whole. The beauty of the automated system is that one owner can select and control the comfort level of the occupants of an entire building or ensure the preservation of items in a sizeable enclosed space.

This remarkable technology started as pneumatic equipment. That means the first HVAC controls were operated by air or gas pressure. Engineers used their fluid control expertise to manipulate cooled or heated air. Once this became standard practice, experts began introducing electricity to the picture. Ladder relays later became switches. Greater currents could soon be carried, and the technology continued to evolve into what it is today. Now, computerized systems are the norm, and can even be controlled via Internet connections. This development means a user does not have to be in the location of the system to monitor and control it. One person can even be in charge of several systems and operate them all from the same location. However, many technicians still require knowledge of pneumatic systems, like boilers, because older buildings like schools commonly continue to use them. As this old system eventually fades out of sight and memory, technicians and environmental managers’ jobs get easier.