November 11, 2021 / RefrigeratorPro Team
If you are planning to purchase an AC, then chances are, you would have come across this term inverter AC. In this post, we will demystify the meaning of inverter AC and how it differs from non inverter AC. Also, don’t forget to go through the pros and cons of inverter ACs!
Table of Contents
How Does a Non Inverter AC Work?
Simple explanation of how AC works is this-
Refrigerant flows in the coils and this process is aided by the compressor. Refrigerant is compressed into hot liquid by the compressor and sent to condenser (outside unit) for loosing heat. This process is aided with the help of a fan that blows hot air onto the condenser. After this, refrigerant flows to evaporator coils, where the refrigerant is cooled further. Now this cool refrigerant flows to the indoor unit and a fan blows from inside towards the coils. This cool air then flows into the room. And the refrigerant goes back to the condenser and the process is repeated.
As you can see, compressor is the heart of an AC. Better compressor technology will give better results. Thus, the main difference between inverter AC and non-inverter one is how the compressor is regulated.
How Does an Inverter AC Work?
Inverter ACs are in-demand these days because of their energy saving aspect. An inverter AC contains an inverter that senses the load required and adjusts the speed of the compressor constantly based on the current temperature, thus providing effective and optimum cooling. It means that an inverter AC’s compressor constantly regulates the temperature.
This is different from Non-inverter ACs, where the compressor will switch off on and off after fixed intervals of time to keep the temperature under the desired range instead of specific temperature. Usually, window ACs do not come with inverter technology. Almost all top AC brands in world come with inverter ACs.
Reading Suggestion: Window AC vs Split AC
Inverter AC vs Non Inverter AC – Differences
Below table gives all the key differences between the Inverter and Non-Inverter AC.
|Non-Inverter AC||Inverter AC|
|Its compressor only switches on or off instead of adjusting as per the current temperature||It contains an inverter drive that controls the motor speed (and compressor speed) as per the required load.|
|The compressor switches on and off automatically after fixed intervals||The compressor runs constantly|
|Produces comparatively more noise while running||Gives quieter operations.|
|They consume more power as they are not efficient||The save good amount of power due to efficient usage by inverter|
|Lifespan is shorter comparatively||Longer life as compared to non-inverter units|
|Suitable for open spaces||Not suitable for open spaces|
|Desired temperature goes slightly up and down because it switches on and off||Temperature does not change because it is constantly monitored by the inverter|
|Price is lower than Inverter ACs||More expensive as compared to non-inverter ones|
Below is cute illustration to explain why inverter ACs are more comfortable. Note: It is only for illustration and actual conditions may vary.
Advantages of Inverter AC Over Non Inverter AC
Low Energy Consumption:
Biggest advantage of inverter AC is that it consumes less power when compared to normal ACs. An inverter AC can consume 25 to 60% less power when compared to regular ACs.
Compressor is the most important part of an AC. Hence, an AC’s lifespan depends on the life of its compressor. Regular ACs come with compressors that are constantly switched on and off to maintain desired temperature. This constant on and off process reduces the life of normal ACs. On the other hand, inverter AC compressor run constantly at low power, this ensures that the life of these compressors is more.
Comfortable Cooling with Precise Temperature Control:
As discussed, inverter ACs do not turn on and off constantly, instead run constantly at low energy settings. This leads to better cooling. How? After reaching the desired temperature, normal ACs turn off, which increases the temperature in some time. As soon as the AC detects increase in temperature, it turns on the compressor, which reduces the temperature again and this cycle continues. But in inverter AC, there is minimal temperature fluctuation because there is no on off mechanism. Hence inverter ACs are more comfortable.
One of the big advantages of inverter ACs is that they produce lower noise and vibrations. This is possible because they use advanced BLDC motors that reduce the contact between moving parts. This leads to higher comfort and convenience.
When we talk about AC warranty, compressor and PCBs are two important parts that should be considered. As far as compressors are concerned, inverter AC compressors usually come with 10-year warranty, which is much higher than 2-to-5-year warranty in normal ACs. Similarly, many inverter ACs come with 5-year warranty on PCBs, which is quite good.
All ACs require refrigerant / coolant that is responsible for release and absorption of heat. Refrigerants used in inverter ACs are eco friendly R32 or R410A. These gases have low Global Warming Potential and low Ozone Depletion Potential. This means that these gases are good for the environment, helping in decreasing your energy footprint!
No Voltage Fluctuation:
Since the compressor is always in ‘on’ state, there is no voltage fluctuation like in normal ACs when the compressor turns on.
Some AC brands such as LG, Haier come with ‘expandable’ air conditioners, which can vary their cooling capacity (tonnage) depending upon the requirement with click of a button. This tech is achievable only in inverter ACs.
Inverter ACs are safe for household wiring since they consume low power. Hence, households that do not have very strong wiring can use these ACs without any fear of fire / damages because of high power consumption.
Disadvantages of Inverter AC Over Non Inverter AC
One of the biggest disadvantages of inverter ACs is their higher price. An inverter AC is at least 20% costlier when compared to a regular 5-star AC. Hence, the difference is higher when compared to 3 or 4-star regular ACs.
Related: 3 Star vs 5 Star AC
Higher Cost of Repair:
Inverter AC comes with inverter compressor, 2 PCBs and several sensors. This not only leads to higher purchase cost, but also higher cost of maintenance in event of breakdowns. Normal ACs usually have only one PCB, while inverter ACs come with 2 PCBs, which means more maintenance. PCB repair for non-inverter AC can cost almost twice as much as normal AC. Sensor replacement is not that costly though.
Lower Efficiency in Extreme Weather Conditions:
Inverter ACs are not the best options when it comes with very high temperatures. For example, in more than 45 – 50 degrees temperature, inverter ACs may not work.
More Time to Reach Desired Temperature:
An AC draws maximum current when the compressor is turned on, due to this regular ACs run at full speed and achieve the desired temperature in short time. However, inverter ACs are built for maximizing power savings. Hence, the compressor does not run at maximum speed when the AC is turned on, which leads to increase in time to reach the desired temperature.
Requires More Upkeep:
90% of normal ACs work efficiently if you keep the filters clean. In short, you do not need much maintenance with normal ACs. However, inverter ACs require regular maintenance, filter cleaning, wet cleaning and so on for it to run efficiently and for higher lifespan. It does not mean that normal ACs do not require proper maintenance, it’s just that majority of the normal ACs can function decently even with lesser upkeep.
Not Ideal for Minimal Use:
If you do not plan to use much, then probably normal ACs are a better choice for you. This is because the savings on power will not be high to offset the higher cost of inverter ACs if you use it sparingly. On top of this, some users turn the AC on and off constantly to reduce the power consumption. This process reduces the efficiency of inverter ACs. Hence, these ACs are best if you want them for moderate-to-heavy use.
Requires Specialized Technician For Repairs:
Inverter ACs cannot be serviced by regular service technicians as the parts and working of these ACs is different. An untrained technician can find it difficult to repair / service the AC and can often escalate the problem instead of resolving the issue. Hence, it is always recommended to utilize the services of technicians of original equipment manufacturer (AC brand).
Power Consumption of Inverter AC vs Non Inverter AC
Biggest advantage of inverter AC is its energy saving aspect. Air conditioners come with BEE star energy rating and ISEER rating, where higher rating means better energy efficiency. Inverter AC and non-inverter AC both come with star energy ratings.
Below table shows the annual power consumption of different types of inverter ACs and non inverter ACs in kWh.
|0.75 Ton AC||1 Ton AC||1.5 Ton AC||2 Ton AC|
|3 Star Non Inverter||627 Units||828 Units||1235 Units||1548 Units|
|3 Star Inverter AC||550 Units||726 Units||1077 Units||1344 Units|
|4 Star Inverter AC||499 Units||658 Units||972 Units||1208 Units|
|5 Star Non Inverter AC||576 Units||760 Units||1130 Units||1412 Units|
|5 Star Inverter AC||421 Units||557 Units||815 Units||1005 Units|
These numbers represent energy consumed when the AC is run for 1600 hours. For example, 3 star non-inverter AC will consume 627 units of power when run for 1600 hours. These numbers represent annual electricity consumption as per BEE data.
This clearly shows that that talking about inverter vs non-inverter AC, inverter AC is a clear winner in terms of energy efficiency. As we can see, 5-star inverter AC is 29% more power efficient than a 5 star non inverter AC. It means that an inverter AC can reduce your power bills by a maximum of 29%.
Types of Inverter Compressors in AC brands in India
All the best split ACs with low power consumption are inverter ACs. We have listed most well knows inverter compressor technologies here.
You will find dual inverter ACs in LG brand. It is sometimes also called twin inverter (Toshiba) or dual inverter rotary compressor (Blue Star).
Dual inverters are more efficient than regular ACs in giving faster and precise cooling.
Regular inverter ACs use BLDC motor to control compressor speed. Dual inverter compressors are more advanced version of these BLDC motors. Regular inverter ACs come with single cylinder-shaped rotary compressor that rotates at high speed, which produces good amount of vibration and noise. This is one of the major drawbacks of BLDC motors.
However, the twin-rotary compressors of dual inverters turn with a phase difference of 180 degrees. This means that the AC unit is more stable while running in full capacity. More stability leads to less vibration and thus, less noise. On top of this, it also ensures variable tonnage. Which means that dual inverter ACs can regulate cooling tonnage from .4 tons to even around 2 tons.
In fact, we have spoken to many LG customers who own dual inverter ACs and we have received positive feedback in terms of noise.
The most common inverter compressor in Whirlpool ACs is the Intellisense Inverter. This inverter enhances the efficiency of the inverter. It is able to achieve this by adding multiple sensors for optimum sensing and cooling.
These sensors detect the number of people in the room and outdoor temperature and adjust the cooling accordingly. Intellisense inverter provide silent cooling with a low noise level of 35 to 40 dB.
Triple inverter is an advanced inverter technology from Samsung. As per Samsung, it gives 67% faster cooling even at high temperature of 68 degree Celcius. It is one step ahead of dual inverters and give more efficient cooling as compared to dual inverters. However, it is more complex technology, therefore, it can mean higher cost of maintenance in case of break down.
Most of the ACs can work decently at around 50 degrees, therefore this is quite high ambient temperature. However, we do not believe that it will be of much use in most parts of the country because temperatures do not go up to this level.
Hitachi ACs use expandable inverter. These inverters are good at expanding their heating capacity as per external temperature changes. It works well Even in the extreme climatic conditions by expanding its cooling capacity and reducing time to reach desired cooling temperature.
Also, these inverters are designed keeping in mind tropical Indian climate with high heat and humidity. It gives an optimised performance in peak loads and cuts heat as well as humidity efficiently.
What is the difference between Inverter, Digital Inverter and Smart inverter ACs
There is not much difference between inverter, digital inverter and smart inverters. Some brands prefer to use ‘digital inverter’ instead of ‘inverter’, while a smart inverter is an inverter where a special microprocessor controls the inverter-compressor. In short, different brands prefer different terminologies and the difference between them is minimal.
Is there a window AC with inverter technology available in market?
Usually window AC do not come with inverter inverter technology, but LG is one of the few brands that offer window inverter air conditioners.
Why is inverter AC called an inverter AC?
Because it comes with an inverter compressor. The inverter chip inside the compressor regulates the speed of compressor to give better regulated cooling.
What is the difference between inverter AC and dual inverter AC
Dual inverter AC is an improvement over inverter AC. While inverter AC has a single rotary compressor, dual inverter AC consists of 2 rotary compressors, and each one operates at a phase difference of 180°. This not only improves the balance but also helps the AC to run at a wide range of speed- from 700 RPM to 8000 RPM. This allows the AC to change their tonnage. For example, a 1.5 ton AC with dual rotary inverter technology can run on a wide range of tonnage from 0.3 to 1.8 tons. LG, Toshiba and Blue Star come with dual inverter ACs.
Dual inverter vs triple inverter AC- What is the Difference?
While dual inverter technology is being used by the majority of top AC brands, 8 pole triple inverter technology was introduced by Samsung. Dual inverter ACs come with twin rotary system containing 2 rotary compressors. However, triple inverter AC does not have 3 rotary compressors. It consists of ‘triple inverter technology’ with 8 poles instead of the usual 4 poles. There is no significant difference between the two in terms of output. However, both the types of ACs are better than regular ACs