VRV / VRF System Install (Multi-Head) SWMS

Installing a Variable Refrigerant Volume (VRV) or Variable Refrigerant Flow (VRF) multi-head system involves mounting a rooftop or ground-level outdoor condensing unit, running long refrigerant pipe sets to multiple indoor fan-coil heads, brazing copper joints under nitrogen purge, pressure testing, evacuating, and charging with R32 or R410A refrigerant. The work routinely combines work at heights above two metres, hot work (oxy-acetylene brazing), confined ceiling space access, electrical interconnection at 415V, and handling of pressurised flammable or asphyxiant refrigerants. Under WHS Regulation 2011 r291 and equivalent state provisions, this combination meets the definition of High Risk Construction Work, making a Safe Work Method Statement mandatory before any work commences. A SWMS is also required to evidence consultation with workers under s47–49, document the hierarchy of controls applied, and satisfy the principal contractor's duty under r309 to obtain and retain SWMS for HRCW carried out on the project.

Hazards identified

7 hazards covered, sorted by priority.

Control measures

Hierarchy-of-controls order: elimination → substitution → isolation → engineering → administrative → PPE.

1. 1Elimination — Pre-fabricate refrigerant pipe sets, brackets and electrical sub-assemblies offsite at ground level to remove brazing and assembly tasks from rooftops and ceiling voids entirely.
2. 2Elimination — Specify pre-charged factory-sealed line sets where pipe runs permit, eliminating field brazing and on-site refrigerant charging operations.
3. 3Substitution — Substitute oxy-acetylene brazing with induction brazing tools or press-fit refrigerant fittings (e.g. flame-free fittings rated to AS/NZS 5149) to remove ignition source.
4. 4Substitution — Use mechanical lifting devices (genie lifts, crane, mini-crane) in place of manual handling for condenser units exceeding 25kg per worker.
5. 5Engineering — Install temporary edge protection meeting AS/NZS 4994.1 around rooftop work zones, or use mobile EWPs with harness anchorage rated to AS/NZS 1891.4 for outdoor unit landing.
6. 6Engineering — Continuous oxygen depletion monitoring (alarm at 19.5% O2) and mechanical ventilation during nitrogen pressure testing and refrigerant charging in enclosed spaces.
7. 7Administrative — Issue hot work permit, conduct 30-minute fire watch post-brazing, isolate combustibles within 11m radius, and verify extinguisher (9L water + CO2) within 3m per AS 1674.1.
8. 8Administrative — Lock-out/tag-out electrical isolation verified with two-pole tester before any termination work; licensed refrigerant handler (ARCtick) and electrical licence holder sign-on required.
9. 9Administrative — Pre-start toolbox talk reviewing this SWMS, refrigerant SDS, rescue plan for confined ceiling space, and emergency refrigerant leak procedure with all workers signing on.
10. 10PPE — Flame-resistant cotton coveralls, leather brazing gauntlets, shade 5 brazing goggles, AS/NZS 1891.1 full-body harness with twin lanyard, AS/NZS 2210.3 safety boots, and cryogenic gloves when handling refrigerant lines.

Applicable Codes of Practice

High-Risk Construction Work triggered

Worked example

On a four-storey commercial office fit-out, a mechanical services subcontractor is installing a Daikin VRV system with a 28kW rooftop condenser and eight ducted indoor heads above the suspended ceiling. At the 6:45am pre-start brief in the site shed, the leading hand opens this SWMS on a tablet and walks the three-person crew through it line by line. The harness requirement for the rooftop landing is flagged — the apprentice realises his lanyard is still in the ute and retrieves it before sign-on. Reviewing the hot work control, the team confirms the ceiling tiles above the brazing location will be removed, fire blanket laid over the cable tray, and a 9L water extinguisher staged within 3m; the site fire warden is notified and a hot work permit issued for the 9am–11am window. During the brazing of the third indoor head, the crew member acting as fire watch notices the nitrogen purge flow has dropped — work pauses, the regulator is reset to 0.2 bar, and the deviation is noted on the back of the SWMS in the 'on-site adjustments' field. After charging, the licensed ARCtick holder records refrigerant quantity, signs the commissioning section, and the SWMS is uploaded to the principal contractor's HSE portal that evening, satisfying r309 retention duty.

Related legislation

• WHS Act 2011 (model)
• WHS Regulation 2025
• Managing the Risk of Falls at Workplaces CoP

Frequently asked questions