Closing the Butcher's Shop: Three Gases, One Cylinder
You are decommissioning the plant room of a butcher's shop that has closed. Three systems are to be removed: a condensing unit on R-22 with a nameplate charge of 9 kg; a freezer pack on R-404A charged with 5.0 kg, which has run for years with a high discharge pressure, a permanently bubbling sight glass and a habit of being topped up 'with whatever was on the van'; and a prep-room split on R-407C with 3.2 kg and a burnt-out compressor. You have a recovery machine, a 26.2 L recovery cylinder labelled R-404A already holding 18 kg, and one empty unmarked cylinder with a damaged valve.
1. Can you use the 26.2 L cylinder for this job? Set out how you would allocate the three charges.
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The 26.2 L cylinder cannot take any more refrigerant. Recovery cylinders must not be filled above 80 % of water capacity: 26.2 × 0.80 = 20.96 L. R-404A liquid density at around 20 °C is roughly 1.04 kg/L, giving a practical maximum of about 21.8 kg. With 18 kg already in it, adding even the 5.0 kg R-404A charge would take it to 23 kg - over the limit and into hydraulic-fill territory.
The unmarked cylinder with a damaged valve is unusable: no identification and a compromised valve mean you cannot guarantee segregation or safe handling, so it must not be filled.
So the job needs purpose-built, correctly labelled, in-date cylinders, and one cylinder per refrigerant. Never mix gases - a cylinder containing R-22 and R-404A, or R-404A and R-407C, cannot be recycled or reclaimed economically and becomes destruction-only waste. Use a liquid/vapour recovery procedure appropriate to each, weigh everything, and pull a vacuum on the recovery machine and hoses afterwards so nothing is left to vent.
2. What can legally and technically be done with each of the three recovered gases?
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R-22 (9 kg) - an ozone-depleting HCFC. Virgin HCFC has been banned for servicing for years, and recycled or reclaimed HCFC for servicing has not been permitted since the end of 2014. There is no legitimate reuse route: the charge must go to a permitted destruction facility as ozone-depleting waste. It must not be sold on, used to top up another R-22 system, or vented.
R-404A (5.0 kg) - air-contaminated. High discharge pressure plus a permanently bubbling sight glass points to non-condensables in the circuit, likely from poor charging practice over the years. Simple recycling removes oil and moisture but cannot remove air, so recycled gas would carry the fault into a new system. It should be segregated, labelled as suspect/contaminated, and either sent to a certified reclamation facility for reprocessing to specification or destroyed. Do not put it back into service.
R-407C (3.2 kg) - burnt-out compressor. The refrigerant may be sound, but a burn-out can leave acid and particulates in the circuit, so it cannot be assumed clean. Recover it, label it, and have it analysed/reclaimed; if analysis is not possible, treat it as waste. R-407C is a zeotropic blend with about 5 K glide, so any reuse requires liquid charging.
3. What documentation and waste obligations apply to this decommissioning?
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You are moving controlled waste, so the paperwork is as important as the recovery itself.
- F-gas records: for each system, the type of refrigerant, the quantity recovered, the date, and the name and certificate number of the technician and company. Retained at least 5 years by both the contractor and, for their own equipment, the operator.
- Cylinder labelling: each cylinder marked with the refrigerant, the gross weight or quantity, and any contamination note. An unlabelled cylinder is unaccounted waste.
- Hazardous waste: R-22 in particular is ozone-depleting waste - it must go only to a facility permitted to receive and destroy it, accompanied by the correct waste transfer/consignment documentation.
- Equipment disposal: the removed units themselves are waste electrical equipment and must not go to general scrap with refrigerant still in them; confirm the circuits are empty and record that they were recovered before the units leave site.
If the shop's operator cannot produce a consignment note for the R-22, that is a gap to raise in writing before you leave the site.