Containment during circuit work, recovery routes, cylinder fill control, evacuation and refrigerant hazards.
Make the section safe before opening
Do not release refrigerant as a shortcut during maintenance or disposal. Use the equipment’s approved recovery or controlled pump-down procedure to remove the charge from the section being opened. Other refrigerant may remain safely isolated elsewhere where the equipment and procedure permit it. Verify the condition of the section; shut service valves do not mean it holds no refrigerant or pressure.
Appropriately qualified people carry out F-gas recovery. At end of life, recovery may take place on site or at an authorised facility receiving the whole equipment. Ordinary scrap collection without an agreed recovery route is different. Permanently decommissioned equipment must not simply be left charged because its casing is staying in place.
Liquid, vapour and cylinder capacity
Recovery equipment may handle liquid and vapour, according to its design and operating instructions. Select the machine, cylinder, hoses and fittings for the refrigerant, pressure and safety class. Equipment approved for an A1 refrigerant may not be suitable for a flammable one.
Use suitable refillable recovery cylinders with clear identification. Check the permitted fill for the cylinder and its contents, and weigh throughout recovery. Initial and final weights support quantity records; continuous monitoring lets work stop before the limit is exceeded. Use another suitable cylinder for the remaining charge.
Liquid expands as it warms. Without sufficient space, that expansion can create dangerous pressure or rupture; the pressure need not bear a fixed relationship to the original system pressure. Pressure does not tell you the stored mass or the capacity left. Follow the cylinder’s storage limits, keep it secured and ventilated, and protect it from heat. A relief device, where fitted, does not make overfilling or heating safe.
After recovery, use the machine’s specified procedure to recover residual refrigerant in the machine and hoses before disconnection. An ordinary vacuum pump must not be used to discharge refrigerant to atmosphere.
Keep recoveries identified and separate
Do not mix different refrigerants casually. An uncontrolled mixture can change pressure, flammability and performance, and complicates later treatment. Unknown contents need their own identified container and specialist assessment.
Recovery is collection. Recycling is reuse after basic cleaning. Reclamation aims to make previously used gas perform to the same standard as unused product in its intended application. Its status remains reclaimed rather than virgin. Specialist separation can reclaim some mixed refrigerants, but composition and contamination determine what is feasible. Other material requires destruction. A mixture may not be ready for reuse, but it may not be beyond reclamation either.
For waste refrigerant, use the required registered carrier, documentation and authorised receiving facility. For other equipment outside the main statutory recovery categories, the recovery duty depends on technical feasibility and proportionate cost. Keep the applicable recovery and disposal records. Servicing with high-GWP reclaimed or recycled gas also has specific legal conditions and deadlines.
Evacuation and pressure testing are different steps
Once the repair and specified tests are complete, evacuation removes air and moisture before charging. Moisture can freeze at restrictions or contribute to harmful chemical reactions with susceptible refrigerant/lubricant combinations. Follow the specified drying and vacuum procedure; evacuation does not replace recovery, strength testing or leak testing.
Use the specified dry oxygen-free nitrogen procedure for refrigeration pressure tests. Oxygen or compressed air can create fire, reaction or contamination hazards. Nitrogen does not remove the risks of stored pressure or oxygen displacement, so the regulator, test pressure and working method still matter. A suitable low flow during brazing limits internal oxidation; this is a separate purge operation.
Exposure, cold liquid and ignition
A refrigerant escape can displace breathable air. Some refrigerants also have significant toxic or flammable properties. Density helps predict movement, but release temperature, ventilation and room layout affect accumulation. Keep clear of a suspect atmosphere, restrict access and arrange competent assessment and safe ventilation before entry; never rely on smell alone.
Concentrated CO2 can be harmful even before an oxygen monitor alone gives a useful warning. Select detection for the actual hazard and verify its operation. Ventilation lowers concentrations but does not guarantee every part of a room is safe.
Low-boiling liquid refrigerant can flash and evaporate on release, drawing heat from skin or eyes and causing severe cold injury. Wear the specified gloves and eye protection. For flammable refrigerants, control ignition sources and use equipment approved for the job alongside suitable ventilation and leak management. Locate leaks with an appropriate detector or leak-detection fluid, never a flame.