It can get uncomfortably hot in the summer months prompting people to go in for installing air conditioners in the house. The question then veers to the electricity consumption. Now, one has to admit that using an air conditioner can cause the electricity bills to soar. However, one can bring it under control by using the right kind of technology and the equipment to go with it.
This brings us to the discussion on the different types of technology in use. One of the revolutionary techniques is the use of Inverter technology. Let us have an introduction into the Inverter ACs. Let us see how these Air Conditioners work.
Table of Contents
- 1 Introduction to Inverter ACs
- 2 Let us look at the major parts of the split AC
- 3 The working of the inverter AC:
- 4 Comparison between an Inverter AC and a BEE 5-Star Normal AC:
- 5 Copper Coils vs Aluminium coils: Which is better?
- 6 Final words
Introduction to Inverter ACs
The compressor is the heart of the AC. In a traditional AC, the compressor switches on and off at regular intervals. You have temperature settings in any AC. When the AC cools the room up to the set temperature the compressor switches off. It remains so until the temperature in the rooms goes up again. On sensing the same, the compressor starts working again repeating the same procedure.
Coming back to the inverter ACs, the compressor does not switch off at all. Naturally, you might ask as to how this situation can be better. You can compare the working of the inverter Air Conditioner to the accelerator of a car.
The moment you sense you are speeding too much, you take the foot off the pedal. Thus, you ensure that you provide less power to the vehicle thereby slowing it down automatically without applying the brakes. Similarly, when you feel the need to speed up the car, you press your foot down again and provide the requisite power to fuel the engine. The inverter AC units work in a similar fashion.
What is the difference between an Inverter AC and a non-inverter AC?
This is a good question. You can see the differences unfold as you go deep down into the article. The basic difference between the two is that the compressor in an inverter AC works continuously whereas it switches between on and off in a non-inverter AC.
The inverter AC units work at variable speeds whereas the non-inverter AC units do so at fixed speeds. This enables the inverter ACs to adjust their tonnage according to the size of the room. The normal AC units do not have this ability.
These are the basic differences. We shall go into the details of the individual differences at the appropriate time.
In order to understand the differences between the normal ACs and the inverter ACs, one should have a background into the working of these ACs. Let us look at the same in the following couple of paragraphs.
The working of the normal ACs
The window AC units are literally out of fashion. Hence, we shall look at the split AC or the ductless ACs as they are called in many parts of the world. Of course, the technology in use in both these variants is similar in many ways. Let us concentrate on the working of the split AC. It involves the use of principles of evaporation, compression, and condensation.
The components of the split AC are divided into two parts, one placed outdoors and the other indoors. An insulated pipe connects both these separate units. The working of these ACs is elementary. It involves the circulation of a compressed gas refrigerant that cools the air inside the house.
This entails that the refrigerant has to be re-cooled and condensed at regular intervals. The hot air outdoors is the best medium to ensure this functionality. The system makes use of a fan to suck the air from outside and condense the refrigerant.
Let us look at the major parts of the split AC
Compressor: The compressor is the heart and the soul of the AC. In a split AC, you find this component in the outdoor unit. The main function of the compressor is to ensure the circulation of the refrigerant between the condenser and the evaporator coils. It does so in a closed loop.
Condenser Coils: The coils are a network of tubes filled with the refrigerant (usually Freon). The condenser coils have the responsibility to eliminate the heat from the heated gas refrigerant and cool it into the liquid form again. The coils allow the absorbed heat to escape into the outside air. These condenser coils form a part of the outdoor unit.
Fans: The fans have the role of pulling the hot air from the condenser coil and disperse the heat. They are also situated in the outdoor unit.
Evaporator coils: These coils work in the opposite fashion to the condenser coils. These coils contain the refrigerant for removing the heat as well as the moisture from the air whereby the refrigerant evaporates into the gaseous form. You find these evaporator coils in the indoor unit.
Air filters: The job of the air filters is to trap the dust, pollen as well as other airborne particles and prevent them from entering into the air conditioning system. These filters play a great role in ensuring the quality of air inside the room.
Drainage system: natural, you find this system outdoors. Water is an important by product of the condensation process. You need to flush out this water from the system. There is an urgent need to keep this system in perfect working condition. Any clogging of the drain pipes can affect the functioning of your air conditioner.
Now that you have seen the different parts of a split AC, you need to understand how it works as well. You can break down this system into four main parts.
- The first step is the compression of the gas and converting it into a high-pressure hot liquid.
- The condensation of this liquid is the second step in the process. The process takes place when the hot liquid flows through the condenser coils. The heat escapes outdoors and the liquid becomes cold. However, the liquid is still under high pressure.
- The expansion valve has the role of converting the high-pressure liquid into a low-pressure liquid.
- The final step involves the passing of this low-pressure liquid through the evaporator coils where you can see the absorption of the heat from the room. This heat converts the liquid into gas. Now, as the heat is absorbed, you get the cooling effect inside the room.
The entire process keeps on repeating.
In the regular AC, you find that the compressor works at full capacity and ensures that the room temperature reaches the desired level. On doing so, the thermostat senses the same and makes the compressor switch off. The fan takes over and enables the circulation of the cool air inside the room. As the room temperature rises, the thermostat sends a signal to the compressor to start working again. This process continues until the time you switch off you AC.
The working of the inverter AC:
The basic process is the same as in the case of the regular ACs. The major difference is that the compressor does not switch off in the inverter AC. The system ensures that it gives more power when the unit needs it and reduces the power when it does not.
How does the AC determine the amount of power it needs to deliver? This depends on the temperature of the incoming air as well as the thermostat setting.
The system uses an inverter to control the speed of the compressor motor. This helps to regulate the temperature levels. Comprising of a variable frequency drive and an adjustable electrical inverter, they are able to regulate the speed of the motors. The system works by converting the incoming alternating current into direct current. Using a modulation process, this system can produce the current of a desired frequency. This system gauges the temperature of the incoming air and adjusts the speed of the motor accordingly. Hence, this accounts for the fluctuations in the load as well.
The inverter ACs are systems that work at varying speeds as compared to the regular ACs that perform at the peak levels at all times.
What are the advantages of inverter technology?
The advantages of using the inverter technology are obvious. Let us look at them in brief.
The inverter AC units consume less power in comparison to the regular ACs.
- The inverter AC units work at varying speeds and tonnage capacities. This is very much unlike the regular AC units that work at fixed speeds and tonnage.
- They maintain the temperature level in the room according to the thermostat setting accurately.
- In comparison to the regular AC units, the inverter units make less noise.
The following example should make things very clear.
You know that every AC has a maximum peak load. It can be a 1-ton AC or a 1.5-ton AC depending on the size of the room. The problem with the normal 1.5-ton ACs is that they run at the peak power requirement as long as the compressor is functioning. This is not the case with the inverter AC. It draws as much power it requires to keep the compressor motors running. Since this system works at varying speeds, the power consumption varies accordingly. Hence, you experience saving of power in the long run.
When you speak about the advantages of the inverter technology, you should have an idea about the drawbacks as well.
The biggest drawback is that inverter ACs can be more expensive than the regular ones. However, it makes up for the fact by reducing your electricity consumption bills by more than 30%. Hence, you can recover the excess cost in a minimum of two years.
Comparison between an Inverter AC and a BEE 5-Star Normal AC:
Speed / Tonnage: The normal AC units work at fixed speeds and tonnage levels whereas the inverter AC units have the ability to work at varying speeds and tonnage. This is one of the biggest distinguishing features.
Automatic adjustment: The inverter AC units have the ability to adjust according to the temperature of the room. The regular AC units lack this ability.
Power consumption: Statistics show that inverter AC units consume far less power than the normal units. In fact, a 3-star BEE inverter AC is 7% more efficient than a 5-star non-inverter AC.
Costs: An inverter AC can definitely cost more than a regular BEE 5-star AC. However, you can compensate by saving on your electricity consumption.
Power consumption: Inverter AC vs Non-Inverter AC
You have ACs of varying capacities and efficiency ratings. In the normal course, the 5-star ratings are considered the most energy efficient systems. Normally, people install AC units of at least 1.5-ton capacity. Hence, we shall compare the power consumption of a 5-star non-inverter AC with a 3-star inverter AC. We shall also look at the comparative 5-star inverter AC to understand the benefits that accrue to the consumer.
As per BEE statistics, a 5-star non inverter AC of 1.5 ton capacity consumes 1130 units of power in 1600 hours. The corresponding figure for a 3-star inverter AC is 1077 units in 1600 hours. As you go for higher efficiency inverter ACs, the power consumption reduces to 972 units and 815 units for a 4-star and 5-star inverter AC respectively.
This is ample proof that inverter ACs can help in saving considerable power.
How does an inverter AC save power?
The regular AC cools the room a little below the thermostat setting and switches off the compressor until the room becomes warm enough. On sensing the warmth, it starts the compressor again. This process of switching the compressor on and off consumes higher power.
The inverter AC units, on the other hand, works at double the capacity to cool the room faster and then slows down the compressor motor considerably to maintain the cooling throughout. As and when the temperature inside the room rises, it releases more power thereby controlling the use of electricity throughout.
We shall see a small example to prove this fact. A 1.5-ton inverter AC will initially run at 150% of its speed to cool the room faster. On doing so, it reduces the speed to around 10% so as to maintain the requisite temperature. This varying speed and tonnage can result in the saving of power. The compressor does not switch on and off at regular intervals thereby saving power as well.
Star ratings for Inverter AC
Just as any other electrical or electronic appliance, you have star ratings for inverter Air Conditioners as well. The ratings depend on various factors such as power consumption, efficiency, etc. The higher the star rating the higher will be the efficiency. At the same time, the price of a 5-star inverter AC will definitely be higher than that of a 3-star inverter AC. Naturally, the power savings in the higher rated version will be more.
What is a dual inverter AC?
The dual inverter AC is an improvement on the normal inverter AC in the sense that it has dual rotary motors with wider rotational frequency. You see an immediate surge in the efficiency levels with faster cooling and emission of lesser noise. It works in a similar fashion to the normal inverter AC by regulating the speed of the compressor motors. However, the dual inverter AC performs the role with a higher degree of efficiency. Hence, it ensures further savings in power bills whereby you recover the cost in double quick time.
In the normal course, ACs work well when the outside temperature is below 46 degrees Celsius. The dual inverter ACs can function when the temperature levels rise above 46 degrees up to a maximum of 52 degrees. Thus, you can see that the dual inverter AC can work in extreme conditions as well.
Copper Coils vs Aluminium coils: Which is better?
The coils play a very important role in the functioning of an AC. You have the condenser coils and the evaporator coils. Each of these coils has its specific duty. Naturally, you require them to function efficiently. In the normal course, copper is the most popular choice for the manufacturing of AC coils. However, copper can be expensive. Hence, aluminium coils are the best alternative. Let us make a comparison between the copper coils and the aluminium coils and see who wins the race.
Transfer of heat
The main function of the coils is the transfer of heat. Copper has a higher heat transfer coefficient when compared to aluminium. Hence, copper coils are better when it comes to heat transfer.
Copper is definitely costlier than aluminium. Therefore, an AC with copper coils can be expensive and out of reach of many people. The use of aluminum has brought a sense of sanity as well as parity to the issue. This reduces the manufacturing price of the ACs considerably. Hence, aluminum coils are better when it comes to considering the cost factor.
Aluminium is more malleable than copper. You can give it any shape you desire. Statistics show that you require three times more copper to equate with the size and shape of aluminum coils. This can make it a costly affair. Certain manufacturers have found a way out by reducing the thickness of the copper coils. Flexibility wise, aluminium is any day more comfortable than copper.
Copper is definitely more durable and long lasting than aluminium. When damaged, you usually have to replace aluminium coils. It is not the case with copper coils. You can repair and reuse them. Hence, copper wins as far as durability is concerned.
The durability has a direct impact on the maintenance of the coils. As copper is more durable, the maintenance costs reduce drastically. It is difficult to maintain aluminum coils in comparison. Therefore, copper is preferable over aluminum in the maintenance category.
The atmospheric and climatic conditions play a vital part in the maintenance of the coils. Corrosion can always happen over a period. This can have a great effect on the heat transfer process. There are chances of developing leaks as well. This can have an adverse effect on the functioning of the ACs.
The compressor has to work harder to maintain the same efficiency levels thereby reducing the life expectancy of the AC unit. Hence, one should take care of both types of coils, copper as well as aluminum as far as corrosion is concerned.
You have just seen the difference between the use of copper coils vs aluminum coils. In some categories such as heat transfer, durability, and maintenance, the copper coils have an upper hand. At the same time, aluminium is comparatively cheaper and definitely more flexible than copper. Hence, we have a mixed reaction to the issue. Both these coils have their individual advantages and drawbacks. It boils down to how you use the AC and maintain the same with regular servicing.
How do you negate the corrosion factor?
The main objective is to protect the condenser as well as evaporator coils from humidity and moisture. One way of doing so is to paint these coils with anti-corrosive materials. Certain brands of ACs use the ‘Blue fin condenser’ to protect the condenser coils from humidity. This technique is very helpful to protect the AC units that are exposed to the higher levels of salt content in the moisture.
You can also make use of micro channel condenser coils to negate the effect of corrosion. The refrigerant flows through micro channels made of aluminium. This system makes the use of flat aluminium fins between the tubes and the refrigerant manifolds.
This system involves the use of aluminium alone and hence, protects against galvanic corrosion. This type of AC system is a good option for people living in the coastal areas where you have a high concentration of salt in the atmosphere.
You have seen the concept of the Inverter AC. Now, you are aware of the benefits of using the inverter technology as well. However, it is of utmost importance to ensure that you maintain your AC systems well by cleaning the filters and ducts regularly. This enables you to save considerable power and increases the life expectancy of your inverter Air Conditioner.