One of the first aspects of an HVAC system to consider is its infrastructure and how these parts contribute to the overall functioning of the HVAC automated system.
Controllers are the information centers of the system. The controllers both receive and send information: These abilities to receive as well as send information are called input and out capabilities. Information that the controller receives include temperature, humidity, pressure, current flow, and other important contributing factors to the system. The output capabilities help run the whole system. The types of controllers that are used are programmable logic controllers, system/network controllers, and terminal unit controllers. Controllers can be both analog or digital.
Occupancy is, in a basic sense, the modes of the system. These “modes” include Unoccupied, Morning Warm Up, and Night-time Setback. The systems running will be adjusted based on the schedules of its occupants: most buildings are zoned, and in many cases make allowances for sections of the building to be set to various temperatures based on the preferences of those in the particular zones. An example of how occupancy works is: Morning Wakeup mode occurs hours before the building users are expected to arrive. The time of Morning Wakeup is based on how long it will take for the system to get the building to Occupancy pre-set levels.
Lighting is often a part of HVAC building management systems. Occupancy schedules as is rightly assumed, affects lighting schedules. The lighting control system can be set to turn lights on at particular times, dim lights, and more. Advanced technology allows for a photocell which will sense when the natural light changes outside and adjust when the building’s lighting system is turned on and off.
Air handlers help those who use automated HVAC systems save money by mixing outside and inside air, so air conditioning and humidity controls are needed less. Air mixing also helps maintain the quality of air and keeps the air circulating throughout the building clean and healthy for it’s occupants to breath. There are a few different types of air handlers that your HVAC automated system may have:
- Constant volume air-handling units – this type is the less efficient of the air handlers, because the fans of this unit don’t have variable-speed controls on it’s fans.
- Variable volume air-handling units – in contrast, this system is the most efficient, because it’s fans’ speeds can be adjusted
- Air handling unit with Discharge Air Temperature control – This system is adjusted so that certain zones will receive less attention based on the preset temperature, therefore contributing to the system’s overall efficiency.
- VAV hybrid systems – This system is a hybrid between the constant volume air-handling unit and the variable volume air-handling unit. The inner zones are treated by the system as those in Variable volume system and the outer, as those in a constant volume air-handling unit.
The central plant is an essential part of the HVAC system for it supplies the system with the water needed to run the system. The central plant has the capability to supply cool water, hot water, condensed water, and help in the functioning of transformers and emergency power systems. The need for these temperatures of water is dependent on several factors including the type of system in your building and the season’s temperature.
- Chilled water system – chilled water is used both for regulating air temperature and maintaining the building equipment.
- Condenser water system – if your automated HVAC system has chillers, then condensed water is needed for cooling the air of the system
- Hot water system – the hot water is part of the buildings heating process
Alarms and Security
Every automated HVAC building management system has an alarm system to notify you of system failures and problems. These alarm systems can detect a variety of problems and can send you a message via text, email, and more. An aspect of these systems is their security: Occupancy sensors can be used as part of the alarm system. Not only do building management systems address physical security issues, but they themselves have to be outfitted with their own security systems for hackers and similar people with ill intentions and can penetrate a building if an automated HVAC building management system does not have proper security in place.