Recovering R-32 from a Failed Split

Calculation

• 1.15 kg x GWP 675 (R-32) = 776 kg CO2e = 0.78 tonnes CO2e

What that means

• At 0.78 t it is below the 5 t CO2e threshold, so no leak-checking duty and no F-gas log obligations attach to this equipment.
• That does not mean the gas can be released. The deliberate release of fluorinated greenhouse gas into the atmosphere is prohibited regardless of charge size. There is no small-system exemption from the venting ban.

'It hasn't worked since March' That is exactly the trap. A unit that has stopped working may have lost most of its charge, or it may still hold liquid in the evaporator, the accumulator or the compressor sump. A sealed circuit does not care that the compressor has failed.

Consequences of cutting corners: brazing, cutting the pipework with a saw, or unbolting the flare connections on a system that still holds R-32 will vent it, and brazing a charged line can produce a blowtorch effect and toxic decomposition products. Recover before disconnecting, whatever the charge. Record the recovery and the quantity on the job sheet.

Not as it stands.

Why 0 bar is not empty A gauge reading 0 bar is reading gauge pressure; the cylinder still contains R-410A vapour at about 1 bar absolute. It is not evacuated, and it is marked for a different refrigerant.

What must be done first

1. Recover the residual R-410A vapour into the R-410A reclaim stock, so the cylinder is genuinely empty and under vacuum.
2. Re-label the cylinder for R-32 - contents, date, technician - before any R-32 goes into it.
3. Check the cylinder's test date (in date here) and its general condition.
4. Observe the fill limit: never exceed 80% of the cylinder's water capacity with liquid, and weigh the cylinder rather than relying on feel.

Risks of skipping it

• Contamination: the mixture becomes an unidentified gas. It cannot be reclaimed to a specification and has to be destroyed, which is a cost to somebody.
• Safety: R-32 is A2L (mildly flammable). Diluting it with an A1 gas does not make the resulting mixture predictably safe, and the cylinder can no longer be treated as either class.
• Traceability: a cylinder whose label does not match its contents is the single most common way bad gas enters a system on the next job.

Safety on this job

• Flammability: R-32 is A2L. No smoking, no hot work, no grinder, no ignition sources within the work zone; ventilate the apartment, and remember the indoor unit is a metre from a gas hob.
• Equipment rating: an A1-rated recovery machine is not automatically suitable for A2L. Confirm the machine is rated for A2L before connecting it, or use one that is.
• Bonding and earthing: static is a real ignition route during recovery; bond the unit and the cylinder.
• Cold burns: liquid R-32 boils at about -52 degrees Celsius at atmospheric pressure. Gloves and sealed goggles, and never trap liquid against skin.
• Leak detection before and after: check the joint areas before brazing on the replacement, and pressure-test with OFN rather than refrigerant.

Refrigerant and equipment

• Recovered R-32 is a single-component refrigerant and can be sent for reclamation; if not reclaimable, it goes for destruction. Either way, only through a permitted operator, with a record of the quantity and the destination.
• The old unit is waste electrical and electronic equipment. It may only leave site once the refrigerant has been recovered, and it should travel with a handover note. It does not go into the general bulky waste, and the caretaker should be told so in writing.