R32 has become the go-to refrigerant for new split systems and heat pumps in New Zealand. It's efficient, it uses a smaller charge than R410A, and its global warming potential (GWP) is about a third of R410A's: 675 against 2,088. Under a quota system based on CO2-equivalent, that gap matters, and it's pushing the market steadily away from R410A.

R32 also handles differently from the refrigerants many of us learned on. Here's what you need to get right on site.

1. Understand the flammability rating: A2L

Refrigerants are classified under AS/NZS ISO 817 by toxicity and flammability. R410A is A1, meaning non-flammable. R32 is A2L: low toxicity and lower flammability.

"Lower flammability" doesn't mean "non-flammable." R32 is hard to ignite and burns slowly, but at the right concentration and with an ignition source it can catch. In practice:

• Keep ignition sources (sparks, open flames, non-rated electrical tools) away from the work area whenever refrigerant could be released.
• Work in well-ventilated spaces, and never vent R32 to atmosphere.
• Before brazing, make sure the system has been fully recovered and purged with oxygen-free dry nitrogen (OFDN).
• Check for leaks before you start and after you finish. A leak detector that suits A2L refrigerants is a must-have.

2. Know the standards

Refrigerating systems and heat pumps in NZ must meet AS/NZS 5149 (Parts 1–4), which covers classification, design, installation and maintenance. For split and VRF systems, charge limits for flammable refrigerants are set by AS/NZS 60335.2.40.

The key points for installers:

• Charge limits depend on room size and occupancy. Before you install, check the indoor unit is suitable for the room volume, especially in small bedrooms and offices.
• Joints in occupied spaces must be permanent (brazed or welded). Flare connections are only allowed at the final connection to the unit.
• Larger systems may need refrigerant detection and mechanical ventilation. Plant room detectors must alarm at no more than 25% of the refrigerant's lower flammability limit.
• Pressure test with dry nitrogen, then tightness test, before you charge.

3. Use tools that are rated for R32

Not every tool in an older kit is suitable for A2L refrigerants. The main risk is a spark from a motor or switch while flammable gas is around. When you're upgrading, look for:

• Vacuum pumps with spark-free or explosion-proof motors and switches.
• Recovery machines designed for R32 and other A2L refrigerants.
• Manifold gauges and hoses rated for R32 pressures, with the correct R32 scales and fittings.
• Refrigerant scales for accurate charging. R32 systems use smaller charges, so precision matters more.
• Leak detectors that are sensitive to R32.

R32-ready options at LIMS include:

• Value Series Vacuum Pump R32 (V-i260Y / V-i280Y), with an explosion-proof design and built-in vacuum gauge
• Value L Series Recovery Unit VRR24LOS-R32
• Value VMG-2 Analog Manifold Gauge, available in an R32 version
• Innerco Safe Care Hose Set, with R32/R410A safe care valves
• Elitech MS-870S and MS-1000 digital manifolds, plus the Elitech refrigerant charging scale

4. Pipe ratings and installation practice

R32 runs at pressures similar to R410A, a little higher. Pipework and fittings rated for R410A are the minimum standard, so never reuse old R22-era pipework or fittings without confirming they're rated for the pressure.

Best practice for R32 pipework:

• Use copper rated for high-pressure refrigerants, such as our hard-drawn R410A-rated pipes and accessories.
• Make clean, accurate flares with a quality flaring tool, and torque flare nuts to the manufacturer's spec. Flares are the most common leak point.
• Braze with a nitrogen purge to prevent oxide scale inside the pipe.
• Consider permanent mechanical joints like Vulkan LOKRING. They need no flame, which is a real advantage when working near flammable refrigerants.
• Pull a deep vacuum and confirm it with a micron gauge before charging. R32 systems are sensitive to moisture and non-condensables.

5. Charging and service tips

• R32 is a single-component refrigerant, so unlike blends it can be charged as either vapour or liquid. Always follow the equipment manufacturer's instructions.
• Charge by weight, never by "feel."
• Label the system clearly as containing a flammable (A2L) refrigerant.
• Never mix R32 with other refrigerants, and use dedicated recovery cylinders.
• Make sure you and your team hold the right refrigerant handling certification for working with these gases.

The bottom line

For most installers, R32 doesn't mean a completely new way of working. It does mean tighter discipline on ignition sources, leak checking, charge limits and tool selection. If you get those right, R32 delivers efficient, lower-GWP systems your customers will thank you for.

Need R32 refrigerant, rated tools or pipework? Browse the range at lims-hvac.co.nz or call our team on 09 571-3229. We're happy to help you choose the right setup for your next job.