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Words of Clivet, a simple mean to discover the meaning of the terminology in use.

  • Packaged
    indicates an air conditioning unit with a single section (and therefore extremely compact), as compared to the "split" unit.
  • Set-point
    is the value of temperature, humidity or another characteristic parameter relating to environmental well-being that, when adjusting an air conditioner, is fixed to reach such comfort.
  • Static pressure
    is the delivery pressure of a fan or pump to counteract the system pressure drops. It is measured in Pa or kPa.
  • Liquid cooler
    a machine used to lower the temperature of liquids used in industrial processes (such as water, glycol mixtures, oil) or of the liquid that acts as a source for the water-water or water-air units. Its main components finned packaged heat exchangers and fans.
  • Cooling cycle
    set of changes in state of a fluid by means of which the heat can be "moved" from one section to another. There are 4 phases in the cooling cycle: evaporation, compression, condensation and expansion (or lamination).
  • Electric heat pump
    machine capable of transferring heat from a source at a lower temperature to a user at a higher temperature, thus heating it through the use of electricity. If it is reversible, it allows the cycle to be reversed so that it operates in cooling mode.
  • Cycle inversion
    an operation through which, with a 4-way valve, the evaporator and the condenser exchange functions in a way to be able to heat or cool an environment.
  • Defrosting
    indicates the process for the removal of frost or ice that may form on the external coil of a heat pump with air as source, in heating mode with low external air temperatures. The most commonly used defrosting method switches the operating mode, automatically reversing the cooling cycle. The external coil switches to operation as a condenser, thus heating and melting the frost or ice. A defrosting cycle causes a reduction, albeit slight, in overall system efficiency.
  • Greenhouse effect
    indicates the effect caused by the release of greenhouse gases into the atmosphere. The gases let sunrays pass, whose energy turns into heat, the same gasses do not allow the reflection of thermal radiations towards space, thereby causing an increase in temperature. It is however thanks to the greenhouse effect that the Earth is habitable. Despite this, for some years an excess of gases (especially CO2) has been worsening the effect, causing an increase in global temperatures.
  • Air conditioning
    refers to all the processes used to obtain the conditions of temperature, relative humidity, quality and air movement requested for people's well-being.
  • Condenser
    an exchanger in which the refrigerant condenses (i.e. passes from the gaseous state to the liquid state) and, while cooling down, transfers heat to another fluid (air or water) by warming it up.
  • Compressor
    a device activated by an electric motor that raises the fluid pressure from the evaporation value to the condensation value.
  • Energy rating
    is a product classification based on energy efficiency. Class A is the most efficient, class G the least efficient. The reference to determine the efficiency is the punctual COP.
  • Inverter
    an electronically controlled device used to vary the rotating speed of an electric motor.
  • Heat exchanger
    a device used to transfer heat between two fluids without these mixing with each other.
  • Chiller
    see chiller unit.
  • Chiller unit
    unit providing chilled water (can also be referred to as water cooler).
  • ACS

    domestic hot water

  • Processing area
    zone inside a hypermarket where certain types of food products are processed and packaged. Typical processing areas are: bread bakery, cake bakery, delicatessen, butcher, fishmonger.
  • WSHP
    (Water Source Heat Pump) a decentralised air conditioning system based on heat pumps and thus analogous to the WLHP system, in which the energy source is waste water available from nature, such as water from wells, the aquifer, rivers, lakes and the sea.
  • Workstation
    refers to a set consisting of a PC, a monitor and a printer, used to manage and supervise a system (such as an air conditioning, fire prevention or burglar alarm system).
  • WLHP
    (Water Loop Heat Pump) a decentralised air conditioning system based on water-air or water-water high-efficiency heat pumps, connected by a water circuit that enables energy to be transferred from one unit to the other. The system is able to provide heating or cooling at the same time in different parts of the building.
  • Fan coil unit
    type of ambient terminal unit. It consists of a water-air heat exchanger that heats or cools an air flow by exchanging heat with water, a fan to move the air flow, a filter and a series of adjustable fins for air distribution.
  • Plug fan
    a high-efficiency fan with reversed-blade rotors, driven by a directly coupled motor, and hence without belt-pulley transmission.
  • Cycle inversion valve
    4-way valve that enables the inversion of the operating mode of the cooling cycle.
  • Expansion valve

    an essential and indispensable component of the cooling circuit that triggers the expansion of the coolant, allowing it to evaporate inside the exchanger with the consequent heat absorption.

  • AHU
    means Air Handling Unit.
  • Ambient terminal unit
    is the peripheral device of an air conditioning system placed in the room to be serviced.
  • Roof top unit

    a packaged air conditioning unit, often installed on a roof top, which sends the filtered and treated air (heated or cooled) directly into the serviced environment, making the system simple and quick to install.

  • Common area unit
    an air conditioner serving the communal area of a shopping centre, such as the mall.
  • Humidification
    atmospheric air at any temperature is mixed with water. Humidification is the thermodynamic process with which the desired quantity of water is added to air.
  • Evaporation tower
    a device used to cool the chiller's process or supply liquid, exploiting the latent water evaporation heat. There are open type towers, in which the liquid to be cooled comes into contact with the external air, and closed type towers, also known as evaporation chillers.
  • TEWI
    (Total Equivalent Warming Index) a parameter that assesses the impact of a system on the greenhouse effect. For an air conditioner it considers the direct impact of the refrigerating fluid and the CO2 produced by its operation: the more efficient the system, the lower the TEWI and the lower the environmental impact.
  • Tenant
    the person who leases a commercial space (shop) inside a shopping centre.
  • Supermarket
    a self-service retail point of sale of convenience products, covering a surface area ranging between 400 and 2,500 square metres.
  • Split
    is an air conditioner divided into two sections: the external section is known as the "motor condensing" section, while the external one is known as the "evaporating" section. In portable units, the external sections is only represented by the condenser, connected to the air conditioner by means of hoses.
  • Energy source
    is a natural resource that allows a thermal exchange. The earth or water (underground, ground, river, lake, sea water) are thermal sources.
  • Geothermal probes
    a thermal exchange element used in geothermics.
  • Hydronic system

    indicates an air conditioning system that uses water as an intermediate medium. A chiller cools the water that is pumped through in pipes and sent to the internal units installed in the rooms to be air conditioned.

  • Noise
    data indicating the noise of the machine in the environment.
  • Roof top
    see Roof top unit.
  • Air re-circulation
    with this process, part of the ambient air is expelled for hygiene reasons and replaced with fresh air.
  • Retail
    retail sales and trade.
  • Active thermodynamic energy recovery
    device for reduction of consumption, used in the most modern air treatment systems. It recovers energy contained in flow of air expelled from the served environment, using a dedicated direct expansion refrigeration circuit, reversible in air-air heat pump mode. The energy thus recovered is used as the first high-efficiency step in the production of heating and cooling energy of the entire system.
  • Thermodynamic energy recovery
    device for reduction of consumption, used in the most modern packaged air treatment systems. It recovers the energy contained in the air flow expelled from the conditioned environment, by controlling its delivery on the external finned coil. This energy is used to boost the heating and cooling energy production efficiency of the whole unit.
  • Cross-flow energy recovery
    performs a heat exchange between two air flows, passing them alternatively over a series of coupled plates that are usually made of aluminium. The two air flows are perpendicular to one another, and are supported by special ventilating sections with high static pressure.
  • Energy recovery
    (or heat recovery device) device that recovers heat dissipated by a machine to generate a useful effect. For an air treatment unit, the energy is recovered from the expelled air flow. For a liquid chiller the heat is recovered which would otherwise be disposed of by the condenser.
  • Pilotage
    indicates all the actions and procedures with which a specialist company looks after the development of a shopping centre. It begins with the tenants' design definition phase, moving on to shop installation and fitting control, and arriving at the definition and management of the budget and the definition of the companies contacted for security, cleaning and maintenance services. This process concludes with the obligatory administrative procedures involved in opening the commercial activities inside the structure.
  • Pressure drop
    indicates the reduction in the pressure of a fluid (e.g. water, air or refrigerant liquid) caused by mechanical friction, changes in the section, bends and obstacles that may form inside pipes or ducts.
  • Stepping
    is the reduction of the thermal or cooling yield of an air conditioner to adjust it to the requirements based on the load of the system at a certain time.
  • Shopping park
    retail sales area with at least 3 commercial concerns occupying a total area of 2,500 square metres. The commercial concerns may have separate car parks and buildings and there is no shared management of communal spaces and service areas.
  • Radiant panel
    a terminal thermal exchange system that enables the heating and cooling of wide surfaces such as ceilings and floors.
  • Outlet village
    artificial villages outside town, comprised of numerous monobrand shops made from prefab structures (usually well-known, appealing brands). These shops stock a special assortment and sell at below-retail price.
  • Lamination/expansion device
    a device that lowers the pressure of the refrigerant liquid from the condensation value to the evaporation value.
  • Non food
    a point of sale or department that sells non food products.
  • Goods mix
    range of commercial categories in the same complex. A good example is the presence of clothes, food, multimedia shops, etc. inside the same shopping centre.
  • Megastore
    see Large specialist area.
  • Medium area
    see Large specialist area.
  • Special maintenance
    operations of an exceptional nature, either for overhaul or for improvement, carried out on-site with special equipment or at authorized service centres.
  • Routine/scheduled maintenance
    verification, cleaning and calibration, performed periodically according to a predefined programme.
  • Layout
    indicates how a shop and its window are organised to optimise the display of the products on sale.
  • Hypermarket
    retail sale area subdivided into food and non food departments, covering a surface area of over 2,500 square metres.
  • Ice protection system
    special measure in the refrigeration circuit which prevents the formation of ice at the base of the heat exchanger during operation in heat pump mode.
  • Large specialist area
    a retail sales area operating in the non food sector, covering an area ranging between 400 and 1,500 square metres.
  • GLA
    (Gross Leasable Area) means the gross area that can be leased in retail shopping centres. It includes all areas that produce a rental income, such as the shop window surface, workrooms, store rooms and offices. It does not include the communal areas managed collectively, such as the car parks and the shopping mall.
  • Geothermal
    means the ability to take advantage of the energy in the ground using special devices (geothermal probes) which are buried horizontally or vertically.
  • Shopping mall
    covered streets or squares, only open to pedestrian traffic, hosting shop windows and entrances to shops.
  • Food court
    catering area in a shopping centre. It comprises public concerns such as bars, as well as primarily thematic restaurants (e.g. Mexican, pizza, vegetarian, ice cream, hamburgers).
  • Free cooling
    indicates the cooling of a fluid via the effect induced by low external temperatures, without the activation of the chiller compressors and therefore with energy savings. In the treatment units, the fresh air is placed directly in the environment, while in chillers it cools special heat exchangers where the fluid to be cooled flows.
  • Food
    a point of sale or department that sells food products.
  • Refrigerant/coolant liquid
    is contained in the circuits of air conditioning units and chillers, and through it heat transfer is achieved.
  • Evaporator
    an exchanger in which the refrigerant liquid evaporates (i.e. passes from the liquid state to the gaseous state) and, while heating up, absorbs heat from another fluid (air or water), cooling it down.
  • Eurovent
    is an independent organisation that certifies cooling and air conditioning products. This is the main point of reference for professionals in the filed and for users, who can thus count on the correctness of the data declared by the manufacturers.
  • Direct expansion
    this term indicates that the evaporation of the refrigerant liquid occurs in direct contact with the air to be cooled.
    (European Seasonal Energy Efficiency Ratio) extends the meaning of EER to the entire yearly operation cycle. It is calculated as an opportune combination of various seasonal operating modes defined by Eurovent/CEN, especially those at partial load.
  • Energia eolica
    è una forma di energia pulita e rinnovabile che trasforma, tramite appositi sistemi, l'energia del vento in energia elettrica.
  • Absorbed energy
    is the electrical energy consumed by air conditioners for the operation of their components (i.e. compressors, fans, auxiliary components).
  • EER
    (Energy Efficiency Ratio) for units in cooling mode. An EER equal to 3 means that, for 1 kWH of electric power consumed, the machine makes 3 kWH of cooling power available to cool the environment.
  • Developer
    the person that looks after the development and creation of a shopping centre.
  • Dehumidification
    atmospheric air at any temperature is mixed with water. Dehumidification is the thermodynamic process with which a certain quantity of water is removed from air.
  • COP
    (Coefficient Of Performance) for units in heating mode. A COP equal to 3 means that, for 1 kWH of electric power consumed, the machine makes 3 kWH of thermal power available to heat the environment.
  • Scroll compressor
    composed of two spirals, one fixed and one orbiting, inserted one inside the other. From the exterior, the gas is pushed to the centre of the spirals. Along the way, the volume of the chamber decreases, thus increasing the pressure of the gas. Featuring very few moving parts, it is highly reliable, produces no vibrations and is relatively quiet.
  • Comfort
    is the special condition of well-being created by temperature, humidity, air quality, noise level and light in an environment, based on individual perceptions.
  • Fossil fuel
    a natural substance that, when suitably refined, produces today's fuels such as natural gas, oil (and its derivatives) and coal.
  • CO2
    is the chemical symbol of carbon dioxide. It is produced by human beings when breathing.
  • Shopping centre

    medium or large structure housing a number of specific shops. They make use of communal infrastructures and service areas, managed autonomously.

  • Sensible heat
    is the heat released or absorbed by a fluid with temperature decrease or increase. Together with the latent heat, it determines the total heat.
  • Latent heat
    is the heat released or absorbed when a fluid passes from a gaseous state to a liquid state or from a liquid state to a solid state and vice versa, without temperature variation. For example, when water is heated, it increases in temperature up to 100°C (it is absorbing sensible heat). Over 100°C, if you continue to provide heat (at ambient pressure), the water evaporates, it changes status without increasing the temperature, it is absorbing latent heat.
  • Coil
    is a heat exchanger, normally between a fluid and the air, where the fluid (refrigerant gas or water) flows through copper pipes and the air passes externally. In the construction the copper pipes are inserted in perforated superimposed aluminium sheets (the fins) and expanded so that mechanical contact is established between the copper and the aluminium.
  • WSHP
    (Water Source Heat Pump) a decentralised air conditioning system based on heat pumps and thus analogous to the WLHP system, in which the energy source is waste water available from nature, such as water from wells, the aquifer, rivers, lakes and the sea.