Heating, ventilation, and air conditioning (HVAC) is the use of various technologies to control the temperature, humidity, and purity of the air in an enclosed space. Its goal is to provide thermal comfort and acceptable indoor air quality. HVAC system design is a subdiscipline of mechanical engineering, based on the principles of thermodynamics, fluid mechanics, and heat transfer. "Refrigeration" is sometimes added to the field's abbreviation as HVAC&R or HVACR, or "ventilation" is dropped, as in HACR.
A furnace, referred to as a heater or boiler in British English, is an appliance used to generate heat for all or part of a building. Furnaces are mostly used as a major component of a central heating system. Furnaces are permanently installed to provide heat to an interior space through intermediary fluid movement, which may be air, steam, or hot water. Heating appliances that use steam or hot water as the fluid are normally referred to as a residential steam boilers or residential hot water boilers. The most common fuel source for modern furnaces in North America and much of Europe is natural gas; other common fuel sources include LPG, fuel oil, wood and in rare cases coal. In some areas electrical resistance heating is used, especially where the cost of electricity is low or the primary purpose is for air conditioning. Modern high-efficiency furnaces can be up to 98% efficient and operate without a chimney, with a typical gas furnace being about 80% efficient. Waste gas and heat are mechanically ventilated through either metal flue pipes or polyvinyl chloride (PVC) pipes that can be vented through the side or roof of the structure. Fuel efficiency in a gas furnace is measured in AFUE.
A thermostat is a regulating device component which senses the temperature of a physical system and performs actions so that the system's temperature is maintained near a desired setpoint.
HVAC equipment needs a control system to regulate the operation of a heating and/or air conditioning system. Usually a sensing device is used to compare the actual state with a target state. Then the control system draws a conclusion what action has to be taken.
Water heating is a heat transfer process that uses an energy source to heat water above its initial temperature. Typical domestic uses of hot water include cooking, cleaning, bathing, and space heating. In industry, hot water and water heated to steam have many uses.
Electric heating is a process in which electrical energy is converted directly to heat energy. Common applications include space heating, cooking, water heating and industrial processes. An electric heater is an electrical device that converts an electric current into heat. The heating element inside every electric heater is an electrical resistor, and works on the principle of Joule heating: an electric current passing through a resistor will convert that electrical energy into heat energy. Most modern electric heating devices use nichrome wire as the active element; the heating element, depicted on the right, uses nichrome wire supported by ceramic insulators.
Underfloor heating and cooling is a form of central heating and cooling that achieves indoor climate control for thermal comfort using hydronic or electrical heating elements embedded in a floor. Heating is achieved by conduction, radiation and convection. Use of underfloor heating dates back to the Neoglacial and Neolithic periods.
A ground source heat pump is a heating/cooling system for buildings that use a type of heat pump to transfer heat to or from the ground, taking advantage of the relative constancy of temperatures of the earth through the seasons. Ground-source heat pumps (GSHPs) – or geothermal heat pumps (GHP), as they are commonly termed in North America – are among the most energy-efficient technologies for providing HVAC and water heating, using far less energy than can be achieved by burning a fuel in a boiler/furnace or by use of resistive electric heaters.
A chilled beam is a type of radiation/convection HVAC system designed to heat and cool large buildings through the use of water. This method removes most of the zone sensible local heat gains and allows the flow rate of pre-conditioned air from the air handling unit to be reduced, lowering by 60% to 80% the ducted design airflow rate and the equipment capacity requirements. There are two types of chilled beams, a Passive Chilled Beam (PCB) and an Active Chilled Beam (ACB). They both consist of pipes of water (fin-and-tube) that pass through a heat exchanger contained in a case suspended from, or recessed in, the ceiling. As the beam cools the air around it, the air becomes denser and falls to the floor. It is replaced by warmer air moving up from below, causing a constant passive air movement called convection, to cool the room. The active beam consists of air duct connections, induction nozzles, hydronic heat transfer coils, supply outlets and induced air inlets. It contains an integral air supply that passes through nozzles, and induces air from the room to the cooling coil. For this reason, it has a better cooling capacity than the passive beam. Instead, the passive beam provides space cooling without the use of a fan and it is mainly done by convection. Passive beams can be either exposed or recessed. The passive approach can provide higher thermal comfort levels, while the active approach uses the momentum of ventilation air that enters at relatively high velocity to induce the circulation of room air through the unit. A chilled beam is similar in appearance to a VRF unit.
Building services engineering (BSE) is a professional engineering discipline that strives to achieve a safe and comfortable indoor environment whilst minimizing the environmental impact of a building.
Architectural Engineer (PE) is a professional engineering designation in the United States. The architectural engineer applies the knowledge and skills of broader engineering disciplines to the design, construction, operation, maintenance, and renovation of buildings and their component systems while paying careful attention to their effects on the surrounding environment.
Architectural engineering or architecture engineering, also known as building engineering, is a discipline that deals with the engineering and construction of buildings, such as environmental, structural, mechanical, electrical, computational, embeddable, and other research domains. It is related to Architecture, Mechatronics Engineering, Computer Engineering, Aerospace Engineering, and Civil Engineering, but distinguished from Interior Design and Architectural Design as an art and science of designing infrastructure through these various engineering disciplines, from which properly align with many related surrounding engineering advancements.
Thermal engineering is a specialized sub-discipline of mechanical engineering that deals with the movement of heat energy and transfer. The energy can be transferred between two mediums or transformed into other forms of energy. A thermal engineer will have knowledge of thermodynamics and the process to convert generated energy from thermal sources into chemical, mechanical, or electrical energy. Many process plants use a wide variety of machines that utilize components that use heat transfer in some way. Many plants use heat exchangers in their operations. A thermal engineer must allow the proper amount of energy to be transferred for correct use. Too much and the components could fail, too little and the system will not function at all. Thermal engineers must have an understanding of economics and the components that they will be servicing or interacting with. Some components that a thermal engineer could work with include heat exchangers, heat sinks, bi-metals strips, radiators and many more. Some systems that require a thermal engineer include; Boilers, heat pumps, water pumps, engines, and more.
Voltage optimisation is a term given to the systematic controlled reduction in the voltages received by an energy consumer to reduce energy use, power demand and reactive power demand. While some voltage 'optimisation' devices have a fixed voltage adjustment, others electronically regulate the voltage automatically.
Photovoltaic thermal collectors, typically abbreviated as PVT collectors and also known as hybrid solar collectors, photovoltaic thermal solar collectors, PV/T collectors or solar cogeneration systems, are power generation technologies that convert solar radiation into usable thermal and electrical energy. PVT collectors combine photovoltaic solar cells, which convert sunlight into electricity, with a solar thermal collector, which transfers the otherwise unused waste heat from the PV module to a heat transfer fluid. By combining electricity and heat generation within the same component, these technologies can reach a higher overall efficiency than solar photovoltaic (PV) or solar thermal (T) alone.
HVAC is a major sub discipline of mechanical engineering. The goal of HVAC design is to balance indoor environmental comfort with other factors such as installation cost, ease of maintenance, and energy efficiency. The discipline of HVAC includes a large number of specialized terms and acronyms, many of which are summarized in this glossary.
FINE MEP is a BIM CAD software tool for building services engineering design, built on top of IntelliCAD. It provides full IFC support, according to the 2x3 IFC Standard. FINE BIM structure, enables a smart model shaping and high design accuracy, directly applied to the real 3D-building model and its building services. Not only the building elements, but also the components of the mechanical/electrical installations themselves are all intelligent objects carrying their own attributes and interacting among each other. MEP design is supported by specific CAD commands and further facilitated through sophisticated recognition and validation algorithms, providing a user-friendly modeling environment.
Heating films are a method of electric resistance heating, providing relatively low temperatures over large areas. Heating films can be directly installed to provide underfloor heating, wall radiant heating and ceiling radiant heating.
Jaros, Baum & Bolles Consulting Engineers, LLP (JB&B) is an American MEP and consulting engineering firm founded in 1915 by Alfred L. Jaros, Jr. and Albert L. Baum. The firm is best known for high-rise projects, including One World Trade Center and Hudson Yards in New York City, the Willis Tower in Chicago, and the Bank of China Tower in Hong Kong. In 2020, JB&B was named New York's Design Firm of the Year by Engineering-News Record magazine.
