Condenser coils are an important part of the AC. You can see the condenser coils on the outdoor unit of your air conditioner, these coils surround the outdoor unit and help in releasing the heat into the environment. The same coils are also found in the indoor unit just below the air filter and are called evaporator coils.
Since the coils play such an important role in the cooling process, the material from which they are made is quite important. The material has to fulfil the purpose of heat exchange but also has to be durable and cost-effective. Generally, these coils are made up of copper or aluminium.
If you are planning on buying a new unit and wondering which of the two metals is better in regards to the performance of the AC, then this article is going to give you all the necessary information needed to make that decision. Read along to find out whether copper or aluminium is best suited for your household.
Importance of coils in an AC:
In an AC, coils are present in two places, one in the evaporator in the indoor unit and another in the outdoor unit in the condenser. In both places, these coils play an important role in the cooling process.
It is through these coils that the exchange of heat takes place. This is why they are made up of materials that are good conductors of heat such as copper and aluminium. The coils also help in changing the state of the refrigerant from gas to liquid and then back to gas which is a major part of the heat exchange process.
Copper Coil Vs. Aluminium Coil:
These days you will find mostly copper or aluminium are being used in these coils. Let us compare both the copper and aluminium coil on various factors and find out which is better for an AC unit.
1. Heat conduction:
As the main function of the coils is to facilitate the exchange of heat, the material used in the coils has to have a high heat conductivity. This will make the process faster and easier. In terms of heat conductivity, copper is a better heat conductor.
Copper has a heat conductivity of 231 BTU and aluminium has a heat conductivity of 136 BTU. Copper clearly has better heat and thermal conductivity. Aluminium only has 60% of the heat conductivity that copper has.
As the coils are continuously exposed to moisture, they have a high chance of rusting. This is especially true for the condenser coils in the outdoor unit as they are constantly exposed to harsh weather conditions, dust, dirt etc. Therefore, the coil has to be corrosion-free in order to last for a long time.
Both copper and aluminium are equally resistant to corrosion. Copper has very little iron content and therefore does not rust but they do oxidize over a period of time. This oxidation is actually beneficial as this forms a thin film and prevents further corrosion.
Similarly, Aluminium also has very little iron content so they do not rust easily. It however oxidised to form aluminium oxide. This hard oxide layer prevents further corrosion.
Copper has a tensile strength that is almost twice that of aluminium. This makes copper stronger than aluminium. This is also why they can handle damages better than aluminium. Copper coils are also easier to repair in case of any damages. Aluminium coils on the other hand generally need to be replaced completely in case of any damages.
Copper is known to be expensive. Hence, copper coils are significantly costlier than aluminium coils. Copper is also less pliable, therefore more copper is needed to make the same amount of coil than aluminium. Manufacturers prefer aluminium when they need to cut their costs as it is cheaper.
Because copper is expensive, manufacturers have started using very thin copper coils. These coils are not beneficial as they lose their strength and are prone to frequent leaks and other damages.
A good quality copper coil however can handle damages and can be easily repaired.
And as aluminium is difficult to repair and is cheaper, manufacturers use strong and heavy-duty aluminium coils which will last for a long time.
How to protect your AC coils from corrosion
Protecting the coils from corrosion and damages is very important to ensure the longevity of the unit. Currently, copper is largely being used to make the coils. However, these days new and innovative technology is coming out to prevent corrosion and other wear and tear related damages.
These days brands are offering Bluefin condensers and gold fin condensers that are protected against damages. For example, LG offers blue fin condenser technology that is an advanced anti-corrosive material to protect the coil against rusting. Similarly, gold fin technology also protects the coils from rust and corrosion due to its golden hydrophilic coating.
These new technologies cut down your maintenance costs significantly, click here to know more about the gold fin and bluefin coatings.