Koeltechnicus Cat I key terms

Any of the synthetic gases listed in the F-gas regulation whose molecules contain fluorine, such as HFCs, PFCs and sulphur hexafluoride. They are controlled because of their high global warming potential and long atmospheric lifetime.

A number expressing how much heat one kilogram of a gas traps over 100 years compared with one kilogram of carbon dioxide, which is set at 1. It is used to convert refrigerant charge into CO2-equivalent tonnes.

The mass of a refrigerant multiplied by its GWP, giving a common unit for comparing climate impact. It determines whether a leak check, record keeping or leak detection system obligation applies to a given system.

Hydrofluorocarbon: a family of synthetic refrigerants containing only hydrogen, fluorine and carbon. They are not ozone depleting but often have high GWP values, so their placing on the market is being phased down.

Hydrofluoroolefin: an unsaturated synthetic refrigerant with a very low GWP because it breaks down quickly in the atmosphere. Often blended with HFCs to lower the GWP of the mixture.

Ozone depletion potential: a relative figure showing how strongly a substance destroys stratospheric ozone compared with CFC-11, which is set at 1. HFCs have zero ODP, while CFCs and HCFCs have values above zero.

Chlorofluorocarbon: an older refrigerant containing chlorine that strongly depletes the ozone layer. Production and use are banned, and any recovered CFC must be handled as controlled waste.

The stepwise reduction of the total CO2-equivalent quantity of HFCs that may be placed on the market, expressed as a percentage of a historical baseline. It progressively pushes the market toward lower-GWP alternatives.

Supplying or making a product containing a controlled gas available to another party for the first time, usually for payment. This triggers quota and phase-down rules, unlike using equipment already in service.

An allocated allowance, measured in CO2-equivalent tonnes, permitting an undertaking to place bulk HFCs on the market in a given year. Importers and producers must hold sufficient quota before shipment.

A periodic inspection of a refrigeration system with suitable instruments to confirm that no controlled refrigerant is escaping. The required frequency depends on the CO2-equivalent charge and the type of equipment.

Fixed automatic equipment that continuously monitors a plant room or system for escaping refrigerant and alarms when a set concentration is reached. Its presence can extend the interval between manual leak checks.

Any uncontrolled release of refrigerant from a system or component, including losses during servicing or from a joint that is not tight. Operators must repair leaks without undue delay and verify the repair afterwards.

The obligation to document refrigerant charge quantities, leak checks, repairs, recovery and the qualifications of the personnel involved. Records must be kept for a defined number of years and made available to inspectors.

Formal proof that a technician has passed an approved theory and practical assessment covering the safe handling of controlled refrigerants. Category I certification permits work on any refrigeration equipment charge size.

The highest technician certification level under the F-gas regime, covering all refrigeration, air-conditioning and heat pump equipment regardless of refrigerant charge. It authorises leak checking, recovery, installation and servicing across the full range.

Collecting refrigerant from a system into a suitable container and storing it without processing, so it can be reused, reclaimed or destroyed. Venting to atmosphere is prohibited for controlled refrigerants.

Cleaning recovered refrigerant of oil, moisture and particulates by a simple on-site process so it can be charged back into the same or similar equipment. It does not restore the product to virgin specification.

Reprocessing recovered refrigerant in a dedicated plant to bring it back to a specified purity standard, verified by laboratory analysis. Reclaimed refrigerant can be placed on the market as a new product.

A pressure vessel, often grey with a distinct valve, intended for holding recovered refrigerant rather than for charging. It must never be overfilled and must be weighed and labelled with the refrigerant identity.

Air or nitrogen trapped in a system or cylinder that will not condense at normal condensing conditions. It raises discharge pressure and must be removed from recovery cylinders before refilling or transport.

The total mass of refrigerant contained in a system, usually stated in kilograms on the nameplate. It is the basis for calculating CO2 equivalent and for deciding which leak-check obligations apply.

A system in which all refrigerant-containing parts are permanently joined, for example by welding or brazing, with no accessible joints. Such systems are often subject to lighter leak-check obligations.

The working fluid that absorbs heat at low pressure and rejects it at high pressure as it circulates through the refrigeration cycle. Its boiling point, latent heat and GWP determine the design and environmental impact.

The heat energy absorbed or released when a substance changes phase at constant temperature, such as boiling or condensing. It is the dominant heat transfer mechanism in an evaporator and condenser.

The temperature of refrigerant vapour above its saturation temperature at the same pressure. Measured at the evaporator outlet, it confirms that no liquid droplets are returning to the compressor.

The temperature of liquid refrigerant below its saturation temperature at the same pressure. Measured at the condenser outlet, it indicates the amount of liquid column available for the expansion device.

The heat exchanger in which low-pressure refrigerant boils and absorbs heat from the space or product being cooled. Its performance depends on airflow, refrigerant feed and correct superheat at the outlet.

The heat exchanger where high-pressure refrigerant vapour rejects heat to the surroundings and condenses to liquid. Poor heat rejection raises discharge pressure and reduces system efficiency.

The machine that draws low-pressure vapour from the evaporator and compresses it to a higher pressure and temperature. It is the component most vulnerable to liquid slugging and overheating.

A metering device that regulates refrigerant flow into the evaporator to maintain a set superheat, using a sensing bulb on the suction line. It is adjusted for the refrigerant and load conditions.

A refrigerant mixture whose components boil at different temperatures, so the composition of liquid and vapour differs during phase change. It must be charged as a liquid and leaks change the remaining mixture composition.

The difference between the bubble point and dew point temperatures of a zeotropic blend at a given pressure. It must be accounted for when setting superheat and interpreting pressure-temperature readings.

Liquid refrigerant entering the compressor, causing mechanical stress, oil dilution and valve damage. It is usually caused by excessive charge, low superheat or a failed expansion device.

Joining copper pipework with a filler metal melted at a temperature below the melting point of the parent metal, often with a nitrogen purge to prevent internal oxidation. Leak-tight joints are essential in refrigerant circuits.

Pressurising a completed or repaired circuit with dry nitrogen to a defined test pressure and checking for leaks, for example with a bubble solution or electronic detector. It must precede evacuation and charging.

Removing air and moisture from a system with a vacuum pump until a specified deep vacuum is reached and held. It prevents ice formation, acid generation and non-condensable gases in the circuit.

The manufacturer's label on a unit stating refrigerant type, charge mass, electrical data and design pressures. Technicians rely on it to identify the correct refrigerant and to calculate leak-check thresholds.