Inverter Air Conditioners: Making the Best Choice

Inverter technology based air conditioners are relatively expensive but offer several advantages. An inverter AC runs the compressor at different speeds according to the ambient temperature, therefore stacking up well on energy efficiency when compared to a non-inverter AC. Choosing it over other conventional ACs may seem to be a smart decision. But at the best of time and with the best of information and budget, making the final choice can still be a challenge. What can be considered best? The best according to your need, capacity, budget, preference or best according to the environment. Other practical concerns can run the gamut from size and cost to capacity and noise, and after-sales service as well. Here is a compilation of all the things that you would want to know before making the all-important buy.

Inverter or Non-inverter ACs: What Do You Prefer?

In an inverter AC, the compressor (fitted in the outdoor unit) is powered by a variable-speed drive or ‘inverter’ that enables the compressors to run at range of speeds from slow to fast, to match the output required. An inverter unit will gradually increase its capacity based on the capacity needed in the room to cool down or heat up the room. This means the compressor doesn’t need to switch on and off continuously, but instead just speeds up or down as need demands. By not actually having to stop and start several times a day, there’s less stress on the compressor and less electricity is used, which is why inverter models are generally more efficient and cost less to run. They can maintain a set temperature within a narrow range. Many split systems in the market these days are inverter models.

Most conventional compressors run at a constant speed and these types of units vary their capacity by switching on and off at different intervals. Switching on this type of unit will start to run on full load. This can cause more wear and tear on the compressor and uses more power to start up each time. These models aren’t as efficient to run as the inverter models, but can be cheaper to buy.

Types of Air Conditioners

1. Window air conditioner: This is usually utilised for cooling individual room/ chamber/ apartments. A window air conditioner houses all the elements of an air conditioning operation in one casing.
2. Split air conditioner: This consists of an outside metal cabinet that holds the condenser, fan and compressor. It also includes an indoor assembly that holds the evaporator and air handler. 
3. Inverter Air Conditioner: In an inverter air conditioner, an inverter controls the speed of the compressor motor, which continuously regulate the temperature. The DC Inverterunits have a variable-frequency drive that comprises an adjustable electrical inverter to control the speed of the electromotor, which means the compressor and the cooling / heating output.

BEE Star Rating and Labelling of Air Conditioners helps us choose an energy efficient air conditioner.

Why are Inverter Air Conditioners in Demand? 

The inverter air conditioner is by far the most energy-efficient. It is more economical and smooth in operation than the fixed speed air conditioner. It consumes less electricity due to its variable speed compressor and is also good for the environment.

Important Brands of Inverter AC

LG, Samsung, Daikin, Carrier, Midea, Haier, Voltas, O General, Hitachi, Blue Star, Mitsubishi Electric, Whirlpool, Toshiba and Panasonic.

What is Cooling Capacity?

Cooling capacity is the measurement of a cooling system and its ability to remove heat from a space. They can also be described in tons to signal how much water at X temperature can be frozen in X amount of time. For reference, 1 ton of refrigeration is equivalent to 211 kJ/min or 200 Btu/min.

How to choose the right capacity?

The capacity of air conditioners is measured in terms of tons. Split and window ACs are available in various capacities, ranging from 1 to 2 tons. The tonnage of an AC does not refer to its weight; it is a unit used to determine the rate at which an AC can cool a room. In simple terms, a larger room requires an air conditioner with a higher tonnage. A single ton is rated at 12000 BTU. As per international standards, it is said that you require about 20 BTU per sq. feet. 

Advantages of an Inverter AC

• About 30 per cent to 50 per cent cheaper to run as it consumes less power compared to a conventional AC
• No voltage fluctuation caused by compressor
• Maintains constant room temperature
• Efficient cooling and heating
• Can be run on solar panels
• Apart from savings in monthly electricity bill, there is huge savings on fuel if run on backup generator
• The additional price paid for an inverter AC gets recovered in electricity bills within a few months
• Environment-friendly due to the use of better refrigerants
• Safe for household wiring due to lower power consumption
• Suitable for large and small rooms

 Disadvantages of an Inverter AC

• If room is not insulated, power consumption increases and so does the electricity bill
• Efficiency decreases at noon if weather is extremely hot (over 45 degrees C)
• Relatively expensive repair and maintenance due to the expensive service support and the components used
• Models too powerful for the room size may run frequent short cycles to achieve the target temperature. This can result in the room getting too cold or too hot; inadequate dehumidification (that is, not drying the air enough, making the room feel less comfortable); increased power usage and running costs; and wear and tear on the system
• Underpowered models may have to run more often at maximum output and dry the air too much

Keep Your Checklist Handy

• Noise

Check the air conditioner’s noise levels; these can be found in the specifications. Some models have a quiet mode for the indoor unit, and sometimes the outdoor unit too. This may reduce the cooling/heating power or airflow, but will keep the air conditioner running at a very quiet level.

A noisy indoor unit may interfere with your activities, conversation, or sleep. A noisy outdoor unit can disturb you or your neighbours.

• Capacity

The capacity of the air conditioner should be considered depending on the floor size of the room where it will be installed. A rough measure is that an area in the range of 120 ~140 sq. ft area will need a 1 ton AC, 150 ~180 sq. ft area will need 1.5 ton, and 180 ~240 sq. ft area will need 2 tons.

• Star-rating labels

Once you have worked out what capacity you need, compare the star ratings of models of similar capacity. The more the stars (from 1 star to 5 stars), the lower the running costs and greenhouse gas emissions. Air conditioners come with star-rated energy-efficiency ratings; these have been standardized/implemented by the Bureau of Energy Efficiency (BEE), Govt of India. Therefore, any AC with more stars will consume less electricity than one with a lower star rating. Therefore, any unit with more stars will consume lesser electricity than one with a lower star rating. If the regular usage of ACs are more than 4 hrs/day, go for higher star rated (4-5) AC, else 3 star can serve your purpose. 3 star ACs are most popular as mid-range power saving gives consumers a great price advantage as compared to 5 star.

• After-sales services

After-sales service and other add-on features like warranty will certainly be a plus for your purchase. Look for longer warranty and a service-oriented brand that has the capabilities and good network to meet the servicing need of your product.

→What is done in AC servicing?

AC condenser and evaporator coil cleaning. Dust and dirt are core enemies of your air conditioning or AC system as they cause overheating of the system. During AC service, the technician cleans the dust and debris from the condenser coil and evaporator coil and other key components of the system. Air conditioners should be inspected, cleaned, and serviced at least once a year.

→Copper Vs Aluminium coils: Since few years, ACs also come in aluminium coils (Condenser coils) where the cost is slightly lower but has much lesser life/durability. So do not compromise on the cost and always insist for copper coil ACs. They have much longer life and less leakage complaints.

→Installation & cartage: While placing order, clear terms of payment (cash or cheque/draft) installation charges if any as it is generally included in the unit cost. Also, do insist for free home delivery while placing the order.

→Slow down the running costs

Heating and cooling appliances account for about 40 per cent of the energy usage. To save money when running your air conditioner, there are several things you can do.

• Size:Having the correct AC size is an important first step.
• Star ratings:A model with more stars will be more efficient and use less power than a model with fewer stars.
• Make your home as energy-efficientas possible.
• Use economy mode(‘Eco mode’) if your air conditioner has one.
• Set the thermostat (target temperature) to a reasonable temperatureso the system doesn’t have to work too hard and use more power than really necessary.

Comparison at a Glance: Inverter Air Conditioners

For our survey, we shortlisted regular-selling models of inverter air conditioners. We conducted the survey during March 2022.

 

Note: Prices may vary. Please check latest prices at amazon.in or flipkart.com.

ISEER: ISEER stands for Indian Seasonal Energy Efficiency Ratio. It is the ratio of total annual amount of heat that the equipment can remove from the indoor air when operated for cooling in active mode to the total annual amount of energy consumed by the equipment during the same period. Higher ISEER rating means a more energy-efficient air conditioner that can help you save on your energy bills in the long run.