Air Conditioners: Copper Coil Vs Aluminium Coil

There are several factors that you should consider before buying a new air conditioner. And apart from all the features, tonnage, cooling and electricity efficiency, the material of the coil is also an important factor that you should always look at. But what difference does the material of coils make? Which one is better? This post will clear all your doubts.

It is common knowledge that every air conditioner has a metal coil running through them, and this coil is extremely important to the overall functioning of the air conditioner. Most often, the air conditioners contain copper coils, since copper is a superior conductor of electricity. But air conditioners with copper coils are usually more expensive, which is why aluminium coils are used as a cheaper alternative.

There are some basic differences between air conditioners using copper coils and those using aluminium coils. To learn more about these differences, and analyze which metal coil is better, let us first understand the function of coils in the air conditioner.

Air conditioners use two types of coils

1. Evaporator Coils
2. Condenser Coils

Let’s first learn more about each of the two to understand their working. This will also help us better understand the difference between aluminium and copper coils.

How an AC Works?

Refrigerant to an air conditioner is just like the blood to our bodies. As the blood flows in our veins, the refrigerant flows in the coils. The refrigerant is designed to transform from liquid to gas and back to liquid again. The refrigerant is made to travel inside the coils which remove the heat energy from inside the house and release into the outside air. The refrigerant does this all inside the evaporator and condenser coils.

The primary function of both evaporator and condenser coil is to exchange heat. Let’s find out more about the evaporator coil first.

What is an Evaporator Coil?

An evaporator coil is located inside the blower compartment or the indoor unit and is therefore also known as the indoor coil. It consists of hollow metallic tubes/pipes which hold the chilled refrigerant. These U-shaped metallic coils/tubes are lined with thin pieces of metal known as ‘fins’, which bring the passing air closer to the coils in order to maximize the effect of the refrigerant.

A blower fan sucks the hot indoor air and the cold refrigerant inside the evaporator coils removes/absorbs the heat from the air as the hot air moves over the coil. This cools the air that passes over the evaporator coils and this cool air is blown out into your room with the help of a fan.

The hot indoor air that is sucked over the evaporator coils, makes the refrigerant inside the evaporator coil warmer. This turns the liquid refrigerant in a gaseous state. The refrigerant gas then travels to compressor and condenser.

What is a Condenser Coil?

After removing heat from the home, the refrigerant in the gas state travels to the compressor. The compressor applies pressure to the refrigerant, turning it to a liquid state. The hot refrigerant liquid now travels to the condensing coil. An exhaust fan blows air onto the condenser coils which releases heat into the outside air. This cools down the refrigerant in the condenser coil.

The refrigerant then passes through the expansion valve. This valve reduces the pressure of the liquid refrigerant, which rapidly cools it. The liquid refrigerant from the expansion valve is quite cold. The cold refrigerant from the expansion valve (in controlled volume) then travels to the evaporator coil. This process keeps on repeating until the set room temperature is reached.

Evaporator and Condenser coils are made from copper or aluminum because these metals conduct heat easily.

What is the Difference Between Aluminium and Copper?

1. Conducting Heat

This is the main function of the coils in the air conditioner. Even in its natural state, copper is a better conductor of heat than aluminium, and this is why it does a better job of conducting heat and electricity.

Winner: Copper

2. Flexibility

Aluminium can be beaten and stretched out much more than copper, and it is possible to give it any shape that you desire. A lot more copper will be required to make something that can be made with only a little amount of aluminium. To save on manufacturing costs, some AC makers have resorted to using aluminium instead of copper.

Winner: Aluminium

3. Long-lasting

When it comes to durability, copper certainly stands the test of time far better than aluminium does. Aluminium coils need to be replaced the moment they incur any sort of damage. When the same happens to a copper coil, it can be repaired and used again with no problem at all.

Winner: Copper

4. Maintenance Cost

Since the durability and longevity of copper is a lot higher than aluminium, it also requires little to no maintenance at all. When compared to copper coils, aluminium coils can run up a higher maintenance cost because of the number of times that they may need to be replaced.

This is because of the fact that copper coil leaks can be repaired by welding but aluminium coils can’t be welded and hence the complete condenser need to be replaced in case of any leaks.

Although copper coils are expensive, it can be considered as a one-time investment since you will hardly need to change them.

Winner: Copper

5. Corrosion

Both copper coils and aluminum coils are prone to the corrosion caused when layers of moisture or impurities accumulate on the surface of the coil. When it comes to copper coils, this corrosion can be evaded completely by means of periodic cleaning. However, aluminium coils are difficult to maintain, and you will need to change them frequently.

Winner: Copper

Final Verdict

The main complaint that people seem to have against copper coils is their cost. While copper coils are more expensive than aluminum coils, they also provide their money’s worth, since they do not corrode and you will hardly need to replace them. You can consider this to be a cost-effective arrangement.

Aluminum coils, on the other hand, cost far less than their copper counterparts. However, they also need to be replaced frequently, since they are prone to corrosion. The maintenance costs go up, therefore, making the overall arrangement quite expensive.

That is why all our product review experts at Mr10.in seem to love air conditioners with copper condensers so much. You can also check out our experts’ list of best air conditioners in India.

• Best 1.5-Ton Window AC in India
• Best 1-Ton Window AC in India
• Best 1.5-Ton Split AC in India
• Best 1-Ton Split AC in India

So, if you are looking for long-term benefits, you should definitely choose copper coils over aluminum ones.