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• Heat transfer


  Is the movement of heat from a body at a higher temperature to a body at a lower temperature
• Thermal conduction


  Is when heat moves from one object to another object through direct touch
• Thermal convection


  The transfer of thermal energy by actual physical movement from one location to another of a substance in which thermal energy is stored. Heat convection is often the primary mode of energy transfer in liquids and gases. A familiar example of convection is the boiling of water in a pot
• Thermal radiation


  Is electromagnetic radiation emitted from a material that is due to the heat of the material
• HVAC


  Heating, Ventilation and Air Conditioning. Refers to the different systems used for moving air between indoor and outdoor areas, along with heating and cooling both residential and commercial buildings. They are the systems that keep you warm and cozy in the winter and feeling cool and fresh in the summer. They also are the systems that filter and clean indoor air to keep you healthy and maintain humidity levels at optimal comfort levels.
• Theory of heat


  The caloric theory is an obsolete scientific theory that heat consists of a self-repellent fluid called caloric that flows from hotter bodies to colder bodies
• Air conditioning system


  Is an electrical device that is purposely installed for the removal of heat and moisture from the interior of an occupied space
• Heat conduction


  Also called diffusion, is the direct microscopic exchange of kinetic energy of particles through the boundary between two systems. When an object is at a different temperature from another body or its surroundings, heat flows so that the body and the surroundings reach the same temperature, at which point they are in thermal equilibrium. Such spontaneous heat transfer always occurs from a region of high temperature to another region of lower temperature, as described in the second law of thermodynamics
• Cooling


  Is generally achieved in the air conditioning system through a refrigeration cycle, but sometimes evaporation or free cooling is employed. The system can also be made based on desiccants (chemicals that eliminate moisture from the air)
• Subterranean


  Most AC system stores and rejects heat in pipes called?
• Window AC


  These used to be a very common choice for controlling the temperature in a small room
• Portable AC


  Are relatively easy to move, but not as much as their name implies
• Split Type AC


  These ductless systems are quite common in modern homes. They are referred to as split systems because they consist of two units, one kept inside your home and one outside. They can be used to cool or heat single areas, or multi-zone systems can be installed. These have one compressor outside, with several indoor units conditioning the air in various parts of your home
• Ducted AC


  Also known as central air conditioning, can be the most efficient in many situations. This system involves a large compressor on the outside of the building, an internal evaporative unit and ducts that bring conditioned air to various rooms through vents. This system will require some significant modifications to your home and tends to have a high upfront cost
• AC for diverse range of situations


  While ducted air conditioning may be the most efficient choice overall, it wouldn't be suitable for someone who just wants to cool down or warm up a single room
• Evaporator coil


  Lined with thin aluminum fins, it looks and functions almost like a car's radiator except that it absorbs heat instead of rejecting it
• Compressor


  Takes in the warm refrigerant vapor and compresses it into a denser form
• Condenser coil


  It's job is to release heat from the refrigerant
• Expansion valve


  In order to complete the air conditioning process, the refrigerant needs to be transformed back into a cold mist
• Radiant heating system


  In this system, heated fluid is distributed from a warm-water source (e.g. geothermal system, boiler) through plastic tubing that is embedded in the floors, walls, or ceilings of a space
• Hydronic radiant heating


  Heating makes use of hot water tubes that run below the home's floors
• Electric radiant heating


  Typically consist of electric heating cables
• Ceiling


  The most ideal surface for radiant systems due to its unobstructed, invisible, and highly efficient heating and cooling capabilities
• Hydronic system


  Are heating systems that circulate water through pipes to either heat or cool a building
• Loose cable


  Is by far the cheapest way to heat a floor and it's just as effective as the other systems. The drawback is installation time; you have to position the cable in a serpentine pattern, fasten it with lots of hot glue or staples, and then "embed" it. You can't splice sections of cable together to serve a larger room or repair damaged cable (this is true of all electric systems)
• Mesh mats


  The cable comes already woven into a plastic net. The prepositioned cable installs quickly—in less than half the time for loose cable. You simply staple or hot glue the mesh to the floor. As with loose cable, you then embed the cable and mesh. But you can't cut or splice the cable itself
• Solid mats


  Are often the most expensive electric system, but they're also the easiest to install. The cable is completely enclosed in synthetic fabric, plastic sheeting or metal foil. The big advantage is that you don't have to embed it as you do loose cable or mesh mats
• Under-mat


  With under tile versions, you simply smooth the mat onto a bed of thin-set (photo above). Then you spread more thin-set with a grout float over the mat. And after it hardens comb more thin-set over the mat to set ceramic or stone tile as you normally would
• Under floating floor mat

  This solid mat system is even easier to install; you just roll out the mats, tape them together and you're done. You can then lay a floating wood or laminate floor directly over the heated flooring
• Under-floor mat technique


  Some mats are sized to fit between joists, so you can heat the floor from below as shown above—a big advantage if you don't want to replace an existing floor. And you can staple mats between joists to heat the floor above
• Heat pump system


  Is basically an all-in-one unit that functions as both the central heat and ac systems in your home. Has a magical reversing valve that switches the system from cooling to heating
• Ducted heat pump


  Ducts are conduits or passages used in heating, ventilation, and air conditioning (HVAC) to deliver and remove air
• AHU


  Air Handling Unit
• Industrial Air-conditioning


  The main purpose of industrial air conditioning systems is to provide conducive conditions so that the required processes can be carried out and required products can be produced
• Comfort Air-Conditioning

  Energy of food is converted into chemical energy for functioning of brain, lungs, heart and other organs and this energy is ultimately rejected to the surroundings. Also the internal organs require a temperature close to 35C for their efficient operation, and regulatory mechanisms of human body maintain this temperature by rejecting appropriate amount of heat
• Evaporator


  Is a device used in a process to turn the liquid form of a chemical substance, such as water, into its gaseous form- vapor. The liquid is evaporated, or vaporized, into a gas form of the targeted substance in that process
• Natural/forced circulation evaporator

  Natural circulation evaporators are based on the natural circulation of the product caused by the density differences that arise from heating. In an evaporator using tubing, after the water begins to boil, bubbles will rise and cause circulation, facilitating the separation of the liquid and the vapor at the top of the heating tubes. The amount of evaporation that takes place depends on the temperature difference between the steam and the solution
• Falling film evaporator

  This type of evaporator is generally made of 4-8 m (13-26 ft) tubes enclosed by steam jackets. The uniform distribution of the solution is important when using this type of evaporator. The solution enters and gains velocity as it flows downward. This gain in velocity is attributed to the vapor being evolved against the heating medium, which flows downward as well. This evaporator is usually applied to highly viscous solutions, so it is frequently used in the chemical, sugar, food, and fermentation industries
• Rising film (Long Tube Vertical) evaporator


  In this type of evaporator, boiling takes place inside the tubes, due to heating made (usually by steam) outside the same. Submergence is therefore not desired; the creation of water vapor bubbles inside the tube creates an ascensional flow enhancing the heat transfer coefficient. This type of evaporator is therefore quite efficient, the disadvantage being to be prone to quick scaling of the internal surface of the tubes
• Climbing and falling-film plate evaporator


  Have a relatively large surface area. The plates are usually corrugated and are supported by frame. During evaporation, steam flows through the channels formed by the free spaces between the plates. The steam alternately climbs and falls parallel to the concentrated liquid. The steam follows a co-current, counter-current path in relation to the liquid. The concentrate and the vapor are both fed into the separation stage where the vapor is sent to a condenser. This type of plate evaporator is frequently applied in the dairy and fermentation industries since they have spatial flexibility. A negative point of this type of evaporator is that it is limited in its ability to treat viscous or solid-containing products. There are other types of plate evaporators, which work with only climbing film