Glossary

Unit of thermal power still widely used to indicate the cooling capacity of an air conditioner, especially on portable models. The higher the BTU/h figure, the more the unit can theoretically cool a large or heavily sun-exposed room. Cooling capacity is also increasingly expressed in kilowatts (1 BTU/h is about 0.293 W).

Technology that lets an air conditioner's compressor adjust its power continuously, rather than simply switching fully on or off. The result is a more stable temperature, quieter running, and generally better energy efficiency than a conventional compressor.

An air conditioner you can move from room to room, which vents extracted hot air through a hose run out of a partly open window. Needs no installation or professional work, unlike a fixed split unit.

An air conditioner made up of an indoor unit and an outdoor unit linked by a refrigerant line. More efficient and quieter than a portable model, but its installation requires a certified professional to handle the refrigerant.

A device that cools air by evaporating water held in a tank or a filter cartridge. Effective mainly in dry air, it stays noticeably less powerful than a real compressor-based air conditioner, but uses far less electricity.

A function that automatically swivels a fan's head from side to side, to spread the airflow over a wide angle instead of concentrating it on a single spot.

An air conditioner's cooling capacity, expressed in kilowatts (kW) rather than BTU/h on the most recent spec sheets. As a rule of thumb, allow roughly 100 W of cooling capacity per m² of room, assuming reasonable insulation.

An air conditioner able to reverse its refrigeration cycle to produce heat in winter instead of cooling, then working as an air-to-air heat pump. A single unit thus covers summer cooling and economical supplementary winter heating.

The two blocks of a split air conditioner: the indoor unit distributes the treated air into the room, the outdoor unit houses the compressor and expels the heat it captures. They are linked by a refrigerant line fitted by a professional.

The substance that circulates inside an air conditioner's or a compressor cooler's circuit, absorbing heat as it evaporates then releasing it as it condenses. Handling it (charging, topping up, recovery) is strictly regulated and reserved for certified professionals.

A setting that lowers a fan's or air conditioner's speed to reduce its noise level, usually at the cost of a lower airflow or cooling power. Designed for overnight use without disturbing sleep.

A type of compressor used in some premium compressor coolers, designed to be insensitive to vibration, shocks and tilting. Especially valued in motorhomes, 4x4s and boats, where movement is constant.

An electric cooler fitted with a real compressor, just like a conventional fridge, able to reach sub-zero temperatures and stay effective even in high outdoor heat. The most efficient technology, but also the heaviest and most expensive.

An electric cooler with no compressor or moving mechanical parts, and therefore completely silent. Less efficient than a compressor cooler, it maintains a more modest gap from ambient temperature.

An electric cooler that uses the Peltier effect (an electric current through two different materials creates a temperature difference) to cool, with no compressor or gas. Light and simple, but its gap from outdoor temperature stays limited, typically around 15 to 20°C below ambient.

A scale (from A to G since the 2021 EU labelling reform) indicating the electricity consumption of an appliance such as a fridge or a freezer. Since such an appliance runs 24/7 all year round, choosing a good energy class usually pays for itself within a few years through the savings made.

Technology that circulates cold air in a way that prevents frost forming inside a freezer or the freezer compartment of a fridge-freezer, avoiding the need for regular manual defrosting.

The continuous maintenance of a low temperature for a food product, from production through to consumption. Even a brief break in the cold chain encourages bacterial growth and shortens the food's safe shelf life.

The difference between the temperature reached inside an appliance and the ambient air temperature around it. A figure that reveals an electric cooler's real performance better than the minimum temperature alone, which depends heavily on test conditions.

Two freezer formats: an upright freezer opens via a front door and makes organising its contents easier (drawers, shelves), while a chest freezer opens from the top and keeps the cold in better, since cold air, being heavier, doesn't escape when opened.

A fridge with a separate built-in freezer compartment, most often in a 70/30 configuration (70% of the volume for the fridge, 30% for the freezer). The most complete solution for a main kitchen, as opposed to a standalone fridge or freezer.

How long an electric cooler or portable fridge can run on an auxiliary battery or power station before needing a recharge. Depends on the appliance's power draw (in Wh), the battery's capacity, and the outdoor temperature.

Spraying a fine cloud of water droplets which, as it evaporates on the skin or in the surrounding air, brings instant relief. Used on personal devices as well as on patio or pergola installations.

A small fitting pierced with a very fine hole, installed on a patio or pergola kit, that turns pressurised water into a fog of fine droplets rather than a jet. The hole's diameter determines how fine the resulting mist is.

Thermal water sprays (Avène, La Roche-Posay, Jonzac...) are enriched with trace elements and designed to soothe the skin as much as cool it, while a classic mineral water spray (Evian...) mainly aims for a simple cooling and hydrating effect, at a lower cost.

A portable device combining a classic fan with a water tank sprayed as a fine mist, for extra cooling outdoors (festivals, sport, gardening) compared with using a plain fan or a plain mister separately.

A set of pipes and nozzles connected to a garden tap, installed on a patio, pergola or deck, which releases a curtain of fine droplets that cools a whole outdoor area rather than a single person.

Describes a container (bottle, cooler, bag) designed to limit heat exchange with the outside, so it keeps a temperature, cold or hot, for a long time. Not to be confused with 'insulating', which refers to the material used to achieve this effect.

The construction technique behind an insulated bottle or mug: two metal walls separated by a vacuum, which sharply limits heat transfer by conduction and convection. This is what lets a bottle keep water cold, or a drink hot, for many hours.

A stainless steel alloy (18% chromium, 8% nickel) commonly used for quality insulated bottles, flasks and boxes, valued for its resistance to corrosion, its lack of any metallic taste transferred to food or drink, and its durability.

A closure system that automatically seals a mug's or bottle's opening as soon as the release button is let go, preventing any leak even if the container is on its side or shaken inside a bag. A practical alternative to a classic screw cap, especially for use in a car.

How long an insulated container keeps a drink or food below (cold) or above (hot) a given temperature threshold, usually measured over 6, 12 or 24 hours depending on the manufacturer. A figure to compare with some caution, as testing protocols vary between brands.

A soft, foldable container with insulated walls, lighter and less bulky once empty than a rigid cooler. Suited to short outings and carrying several meals or drinks, usually at the cost of lower thermal performance than a rigid cooler of the same volume.

A double-walled insulated lunchbox that keeps a meal hot or cold until it's time to eat, with no microwave or ice needed, handy for the office, school or a picnic.

A pouch filled with a cooling gel, kept in the freezer then slipped into a cooler or insulated bag. Melts more slowly than a regular ice cube and leaves no meltwater behind once thawed, unlike loose ice cubes.

A compact electric appliance that produces several kilos of ice cubes a day in just minutes, without going through the freezer's ice tray or waiting hours for it to freeze.

A small device, often wireless, that measures the actual temperature inside a fridge (ideally between 0 and 4°C) or a freezer (-18°C), more reliable than the sometimes-approximate display on some appliances.

An insulating sleeve kept in the freezer then slipped around a wine or champagne bottle to keep it cool at the table, without the dampness that comes with a classic ice bucket.

A sealed, hollow metal rod, kept in the freezer then inserted directly into a bottle's neck to cool the wine from inside without ever touching the liquid, so it never dilutes it the way an ice cube would.

The unit of measurement for noise level. For a fan or an air conditioner, the lower the stated dB figure, the quieter the appliance. As a reference point, a normal conversation sits around 60 dB.

The volume of air moved by a fan or air conditioner in one hour, expressed in cubic metres per hour. A higher airflow generally cools a larger room faster.

The unit of electrical power. An appliance's power draw (in watts) determines its impact on the electricity bill in use: a fan typically draws a few dozen watts, against several hundred to over a thousand for an air conditioner.

The storage volume actually available inside a cooler, fridge or freezer, often slightly lower than the stated gross volume once insulating walls and internal fittings are accounted for.

A unit of power equal to 1000 watts, commonly used to express an air conditioner's cooling capacity or a large appliance's electrical power, rather than the watt alone which suits smaller appliances like a fan better.

A unit of energy (not power) that indicates the amount of electricity consumed or stored over a given time, used to express a battery's or power station's capacity, and therefore the runtime it gives an appliance such as an electric cooler.

The unit of electrical current. For a 12V-powered appliance (an electric car cooler, for example), the amps it draws give a direct sense of how quickly it drains the vehicle's battery.

Energy-efficiency indicators for a reversible air conditioner, calculated over a whole season rather than at a single point in time: SEER for cooling mode, SCOP for heating mode. The higher these values, the less electricity the unit uses for the performance it delivers.

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A unique numeric code (often shown as a barcode) that precisely identifies a product and its manufacturer, useful for tracking down an exact reference or checking you're comparing the same model across different retailers.

The manufacturer's commitment to repair or replace a faulty appliance for a set period after purchase, generally 2 years in Europe, sometimes longer on certain premium appliances (air conditioners, compressor coolers). Distinct from statutory conformity guarantees, which apply regardless.

The document provided by the manufacturer explaining an appliance's installation, settings and maintenance. Often also available as a downloadable PDF on the manufacturer's website if the paper copy is lost.

The service a manufacturer or retailer offers to handle complaints, repairs and exchanges after a product is purchased, especially during the manufacturer warranty period.