Replacing Copper Pipe Evaporator Coil with Aluminum Pipes

Replacing Copper Pipe Evaporator Coil with Aluminum Pipes

In finned tube heat exchangers—core components found in air-source heat pump water heaters, air conditioner outdoor units, refrigerator condensers, and similar equipment—replacing traditional copper tubes with aluminum tubes has emerged as a key industry focus in recent years. This shift aims to balance cost, weight reduction, and performance.

Core Advantages of Replacing Copper Tubes with Aluminum Tubes

The material properties of aluminum versus copper (such as density, cost, and workability) directly determine the core value of this substitution, offering significant advantages in cost-sensitive and weight-reduction scenarios:

1. Significant Cost Reduction and Enhanced Cost-Effectiveness

Low raw material cost: Copper is a precious metal with high price volatility (2024 copper prices are approximately 3-4 times that of aluminum). Abundant aluminum reserves and low extraction/processing costs directly reduce heat exchanger material procurement expenses (cost reduction of 20%-35% per household air conditioner heat exchanger).

Optimized processing costs: Aluminum's excellent ductility enables direct extrusion molding of complex cross-section flat tubes and microchannel tubes (unlike copper tubes requiring multiple drawing and bending processes), reducing process losses and boosting production efficiency.

2. Lightweight Design Reduces Installation and Transportation Burden

Aluminum's density is approximately 2.7 g/cm³, only 30% of copper's density (8.9 g/cm³). For equivalent heat exchange area, aluminum tube heat exchangers weigh 40%-60% less than copper tube heat exchangers:

For suspended/mobile equipment like home air conditioners and wall-mounted heat pump water heaters, lightweight construction eases installation (by reducing wall load requirements).

For mass-production manufacturers, lightweight design lowers transportation costs (increasing truck loading capacity by over 30%).

3. Natural oxide layer provides inherent corrosion resistance

Aluminum rapidly forms a dense Al₂O₃ oxide layer (approximately 5-10nm thick) when exposed to air. This layer is water-insoluble, resistant to neutral salt spray, and can withstand corrosion in ordinary humid environments (e.g., household appliances in dry regions).

Through surface treatments (such as hydrophilic coatings or chromate passivation), corrosion resistance can be further enhanced to meet requirements in moderately humid environments.

Recommended Applications for Aluminum Tubing

Residential air conditioners / wall-mounted heat pump water heaters: Operating under mild conditions (system pressure 2.0-2.8MPa), in dry/low-salt-fog environments, and where cost and weight are critical. Aluminum tube heat exchangers have become mainstream (e.g., over 60% of residential air conditioners from brands like Midea and Gree use aluminum tubing).

Small-to-medium commercial equipment (e.g., convenience store refrigerators, compact heat pumps): Low heat exchange loads, limited installation space, and high demand for lightweight solutions. Aluminum tubes reduce equipment size and cost.

Dry regions / inland areas: Absence of high salt fog or acid/alkali corrosion. The natural oxide layer of aluminum tubes provides sufficient corrosion protection without requiring additional coatings.