Aluminium for HVAC&R heat exchangers and tubing
Aluminium has become a preferred material for many HVAC&R applications, offering a combination of lower weight, cost advantages, corrosion resistance and recyclability. Hydro supplies aluminium tube for HVAC&R equipment, including tube and fin, micro-channel heat exchangers, and line sets.
Micro-channel heat exchangers
Hydro supplies multi-port extruded (MPE) tube for brazed micro-channel. Micro-channel tubes have inherent technical advantages that result in the highest thermal performance gains possible. The metallic bond between tube and fin eliminates the contact resistance found in mechanically expanded designs, improving heat transfer efficiency. Combined with the micro-channel tube geometry, this supports a smaller, lighter unit and a significant decrease in refrigerant charge. A lower-depth core can also reduce air-side pressure drop by up to 50% compared with a conventional heat exchanger with the same air-side frontal area.
Tube and fin heat exchangers
Tube-and-fin remains the most common heat exchanger design in HVAC&R, and Hydro supplies aluminium tube and fin as a direct alternative to traditional copper tube/aluminium fin coils. Pairing aluminium tube with aluminium fin provides better corrosion resistance through improved galvanic coupling than a mixed-metal design while also delivering immunity to formicary corrosion, a failure mode that affects copper tube. Internally enhanced tube options can improve refrigerant-side heat transfer by increasing inner-surface area and can also influence refrigerant flow characteristics.
Aluminium tubing for line sets
Hydro aluminium tubing for line sets and connecting lines are made with a special alloy developed specifically for HVAC&R applications. Standard dimensions range from 1/4 inch to 1 inch, and customized dimensions are available on request. An optional polyamide (PA) or polyethylene (PE) coating layer provides additional protection against corrosion and physical damage. Installation guidance covers appropriate tooling, torque values and joining methods.
Aluminium vs copper in HVAC&R
When comparing copper and aluminium for HVAC&R equipment, six factors matter most: cost, weight, thermal performance, durability, corrosion behaviour and recyclability.
- Cost: Aluminium is typically priced at around one-fourth the price of copper on a per-tonne basis, and application studies have shown bill-of-material savings in the range of 34–48%. Because aluminium heat exchangers contain significantly less material by weight, fluctuations in LME pricing have a much smaller impact on manufacturing costs than with copper-based designs.
- Weight: As a rule of thumb, an aluminium tube-based heat exchanger weighs only half as much as its copper equivalent. Depending on the design, complete heat exchanger weight can be reduced by 17–34%, while tube weight reductions can reach approximately two-thirds. The lower weight can also reduce handling and logistics costs.
- Thermal performance: In a tube-and-fin design, the difference in overall heat transfer coefficient between a copper-tube and an aluminium-tube exchanger of identical geometry is negligible at approximately 1%. The fin-to-air interface, rather than the tube wall itself, is the dominant factor governing overall performance.
- Durability: In conventional copper tube/aluminium fin heat exchangers, galvanic interaction between dissimilar metals can contribute to gradual fin degradation over time. An all-aluminium design provides a balanced alloy combination that reduces this corrosion mechanism and helps maintain long-term performance.
- Corrosion: Aluminium is immune to formicary ("ant-nest") corrosion, a failure mode estimated to account for approximately 10% of premature indoor heat exchanger failures. Aluminium is also compatible with ammonia refrigerant systems, whereas copper cannot be used because of ammonia attacks.
- Recyclability: All-aluminium heat exchangers can be recycled without first separating different materials, unlike mixed-metal designs. This simplifies end-of-life processing and improves material recovery.
|
Condenser application |
Fin & tube (Cu tube/Al fin) |
Fin & tube (Al tube/Al fin) |
Micro-channel (Al tube/Al fin) |
|
Required space |
100% |
100% |
28% |
|
Tube weight |
100% |
33-66% |
33% |
|
Heat exchanger weight |
100% |
66-83% |
42% |
|
Tube cost per exchanger |
100% |
20-40% |
30% |
|
Refrigerant charge |
100% |
100-86% |
7% |
|
Lifetime |
High fin corrosion |
All-aluminium balanced alloy combination |
All-aluminium balanced alloy combination |
|
Recyclabilty |
Separation needed |
No separation needed |
No separation needed |
How we can support your transition
Switching from copper to aluminium is more than a material change. Success depends on choosing the right alloys, understanding application requirements and implementing proven manufacturing practices. We support customers throughout the transition with specialised materials, technical expertise and decades of HVAC&R experience.
- Proven HVAC&R alloys designed for corrosion resistance, durability and long-term performance.
- Technical expertise to help evaluate designs, applications and manufacturing considerations.
- Workshops and training that provide practical guidance on working with aluminium and adopting best practices across the value chain.
- Proven success built on decades of experience supplying aluminium solutions that have delivered reliable performance in HVAC&R applications worldwide.
- Tools, knowledge and support to help customers minimise risk, avoid common pitfalls and achieve a successful transition.
- A trusted long-term partner with more than 50 years of aluminium extrusion experience, backed by a global technical and manufacturing network.
Explore the possibilities with a complimentary workshop
Considering aluminium for your HVAC&R applications? We offer free technical workshops for manufacturers interested in understanding the opportunities and challenges of transitioning from copper to aluminium.
During the workshop, our specialists can help you:
- Evaluate potential applications and benefits
- Discuss corrosion and durability requirements
- Review alloy and product options
- Share best practices for manufacturing and installation
- Identify key considerations for a successful transition
Whether you are just beginning to explore aluminium or already planning a transition, we can help you build the knowledge and confidence needed to move forward.
Frequently asked questions about copper substitution
Yes. Aluminium can replace copper in tube-and-fin heat exchangers, micro-channel heat exchangers, line sets and many other HVAC&R applications when the alloy selection, coating system and joining method are matched to the operating environment. Aluminium can also be used with ammonia refrigerants, unlike copper.
The HVAC&R industry is increasingly replacing copper components with aluminium because aluminium can offer lower material costs, weight reduction, improved corrosion performance in all-aluminium systems and enhanced recyclability.
Although copper has higher thermal conductivity, the tube material contributes only a small portion of total heat transfer resistance in a tube-and-fin heat exchanger. For matched geometries, the difference in overall heat transfer coefficient between copper and aluminium tube designs is approximately 1%.
Formicary corrosion is a failure mode that affects copper heat exchangers. It is estimated to account for around 10% of premature indoor heat exchanger failures. Aluminium is immune to formicary corrosion and does not experience this failure mode.
