Copper Versus Aluminum Coils HVACWhat you will learn with the Copper Versus Aluminum Coils HVAC article:
1) The transition from copper to aluminum for HVAC manufacturers.
2) The pros and cons of copper versus aluminum for HVAC equipment.
3) Trying something new or keeping the status quo?
4) A video debunking the “aluminum is difficult to repair” myth.
5) Lastly, plenty of resources and in-depth related links to help you learn

The Conductivity of Copper Versus Aluminum Coils | Copper Versus Aluminum Coils HVAC

When it comes to Copper Versus Aluminum Coils for Condensers and Evaporators, what is the best choice? What are the options if I’m a consumer? Some manufacturers are starting to transition from copper coils to aluminum coils for both condensers and evaporator coils for various reasons.

Origins of Copper and Aluminum Discovery | Copper Versus Aluminum Coils HVAC

Copper is believed to have been discovered by the Romans. The Romans mined copper on the Mediterranean island of Cyprus. Aluminum was also around in the Roman Empire, where Pliny the Elder wondered what the silver metal was to Tiberius, the Roman Emperor of the time.

condenser coils make a difference in efficiency

Copper coils covered with aluminum fins

When deciding to buy a new system, you need to inform yourself about the pros and cons of purchasing a system with aluminum coils or copper coils. Traditionally, copper was the chief choice to use to manufacture evaporator coils and condenser coils because of heat transfer rate, cost, pliability (easy to bend and swage), and because copper line sets are used to join split systems.

Moreover, the price of copper has skyrocketed, and that was a game-changer. Furthermore, many manufacturers have started looking at aluminum because the cost of aluminum is cheaper than copper, and aluminum has some of the same benefits of the properties mentioned above that copper has.

Copper has approximately twice the conductivity of heat transfer of aluminum and therefore is more efficient at transferring heat. An air conditioner or heat pump works on the principle of refrigeration. The classic definition of refrigeration is moving heat from one place where it is not wanted to another location where it doesn’t matter. Finally, that means it is crucial to use materials that efficiently move or transfer heat. In this regard, copper wins.

Related Link: Our refrigeration category covers comprehensive information about HVAC refrigeration. (opens in a new window)

Furthermore, another pro for copper is the ease of repairing the copper coils in the field if they become damaged. Finally, aluminum coils, if damaged, are tough to fix and often need to be replaced.

Related Link: HVACR Pipe Soldering Brazing – Refrigeration Systems (opens in a new window)

Pros and Cons of Copper Versus Aluminum Coils HVAC

thinner tubing for condensers and evaporators

Manufacturers producing copper pipe with thinner walls

  1. Heat Transfer
  2. Repair Ease
  3. Galvanic Corrosion
  4. Formicary Corrosion
  5. Material Quality/Durability
  6. Aluminum Repair Ease
  7. Copper Durability
  8. Copper and Aluminum Together
  9. Tradition

Heat Transfer

1Copper has a better heat transfer rate than aluminum

Repair Ease

2Copper is easily repaired in the field when damaged whereas aluminum, when damaged, typically requires an entire coil change

Galvanic Corrosion

3Because the copper line set, copper coils, and fins are aluminum, where the copper joins the aluminum, it is subject to galvanic corrosion. Galvanic corrosion will occur when two dissimilar metals pressed together. Furthermore, modern technology and advancements in joining dissimilar metals have made this con very minimal for aluminum.

Copper Aluminum Periodic Table

Periodic Table of Elements: Copper is 29 and Aluminum is 13.

Formicary Corrosion

Copper is subject to formicary corrosion. Additionally, that is not a problem as long as the coils get proper and regular maintenance.

Material Quality/Durabilty

4Modern technology and the price of copper has made manufacturers use thinner and thinner copper. The new refrigerant replacing the old HCFCs operates at higher pressures; therefore, the newer copper is more likely to spring a leak because of the thinner copper and the higher operating pressures.

Aluminum Repair Ease

5Because aluminum is challenging to repair, manufacturers, use a heavy-duty cabinet to protect the coils. Lastly, that makes it more difficult to clean the coils without disassembling the cabinet.

Copper Durability

6The traditional perception is that copper is more durable than aluminum, but again, that will soon change as the copper gets thinner and thinner because of the rising cost.

Material Theft

7Since copper is costly, it makes it a target for thieves. A contractor friend of mine just replaced some air conditioner condensers and all the copper the thieves could get their hands on, for a church. Now it’s bad enough they hit a church (imagine the implications of that in the afterlife. LOL). Still, it is now necessary to secure copper, including condensing units, to discourage theft. Furthermore, that is an added cost for the end consumer.

Copper and Aluminum Together

8I have read that as much as copper suffers from formicary corrosion, aluminum suffers from bacteria and mold issues. The problem with that argument is that manufacturers have always used aluminum fins over the copper tubing to increase the area for heat absorption and to channel the air more effectively across the coils. Besides that, anyone with mold or bacteria problems need to use a UV Air Cleaner inside their ducts.


9The traditional coils, copper tubing with aluminum fins have functioned for years and years in condensers and evaporator coils. These coils are tried and true, so anything new on the market is subject to some apprehension. Moreover, Trane has been using aluminum for years and years, and they offer a good warranty for their product, so aluminum can’t be that bad for use in HVAC equipment.

Condensing unit with copper coil & aluminum fins

Condensing unit with copper coil & aluminum fins

Traditional Coils | Copper Versus Aluminum Coils HVAC

Additionally, refrigerator and freezer manufacturers have used aluminum coils for many years for the coils in their products. What is your opinion based on the facts? Leave your opinion in the comments below.

Finally, the below video is of a repair to aluminum coils. That is in case of a puncture or leak in the coils. Furthermore, not sure how this stuff would work for joining two dissimilar metals together, such as copper and aluminum, but this is a plus for aluminum coils.

Related Link: If you are purchasing new HVAC equipment you can see our Buyers Advice Category (opens in a new window)

High Performance HVAC Air Conditioning and Heating Systems

Copper Versus Aluminum Coils HVAC