The complete AC buying guide for India

The AC replaces the hot and humid air with the cool air in your room.

Any air conditioner consists of 4 main parts:

• Evaporator
• Compressor
• Condenser
• Expansion valve

All 4 parts are connected together through a coil in which refrigerant flows.

a) Evaporator

It collects heat from the air in the room. The liquid refrigerant such as hydrofluorocarbons and chlorofluorocarbons in the evaporator absorbs the room heat and evaporates into a gas.

b) Compressor

The compressor takes in this refrigerant gas and there it is further compressed. The high pressure makes it hotter and it starts moving fast.

c) Condenser

The heat from the fast-moving refrigerant is absorbed by the condenser, converted into liquid, and expels the heat outside the room.

The condenser is made of copper tubing and aluminum fins.

The hot refrigerant gas is cooled when it passes through the copper tubing and its cooling effect is further accelerated by the surrounded aluminum fins and the fan attached to it.

d) Expansion valve

Thereafter, this cool refrigerant passes through the expansion valve.

This sudden drop in the pressure causes the refrigerant to cool down further.

Finally, it is taken in by the evaporator.

The ambient air when passes near the cold refrigerant, also become cool and the fan attached to it pushes this cool air inside the room.

This cycle repeats and cools the room.

The types of AC

The Air conditioners can also be classified on the basis of their use.

Whether it is used for residential purposes or for commercial purposes.

The residential air conditioners are small in size and are meant for houses and apartments.

While commercial air conditioners are large in size and are designed for big spaces such as malls, buildings, airports, hospitals, hotels, etc.

(i) Window AC

It is the most common type of air conditioner available in the market.

This AC can easily fit into the window of the room.

These are the best for cooling a small and medium size room.

Window ACs are cheap and their maintenance is easy.

(ii) Split AC

It is becoming fast a popular option for buyers.

As the name suggests, the unit is split into 2 parts.

The indoor unit (evaporator, expansion valve) is mounted on the wall of the room and the outdoor unit (compressor and condenser) is either placed outside the room, on the balcony, or on the roof.

Both the units are connected through a coolant coil.

Split AC is costlier than the window ACs.

But these are more efficient, more silent, and save you more power than the window AC.

Choose split AC when your budget is high daily usage is more.

(iii) Central AC

These are used to cool large buildings.

This central AC is installed at the central place of the building or a house.

From there it is distributed to other rooms or the parts of the building

through ducts.

The central AC system is costly, requires maintenance, more complex system.

These are suitable for large houses.

(iv) Portable Air Conditioner

This is a new concept in the Indian market.

The portable air conditioner as the name suggests can be placed and taken to any room of the house.

These units are movable and small in size and have low cooling power.

It is easy to use and has a simple setup.

These are suitable for students living in a single room.

Air Conditioner technology

We see two types of ac technology in the market:

• Normal Air Conditioner
• Inverter Air Conditioner

Nowadays, the inverter technology ac is fast becoming the preferred option for many Indian families due to its energy efficiency and quiet operation.

The basic difference between the two is that in an inverter AC, the compressor adjusts its speed according to the room temperature.

Once the room is cool or reached the desired temperature, the compressor motor slows down to save energy.

While in the case of normal AC, the motor runs at the full speed until the room temperature reaches the set level. Once it is reached, it shuts down.

This repetitive ON-OFF operation not only consumes more energy but also creates more noise.

The energy rating of AC

It is an indicator of the energy efficiency of the ac. More stars mean the ac is more energy efficient.

This star rating is awarded by the BEE (Bureau of Energy efficiency).

The rating of Air Conditioner is indicated in red colors.

If 1 star is colored, it is 1-star AC

If 3-stars out of 5 are colored it is 3-star AC (more energy efficient than the 1-star AC).

The above sticker is provided by BEE, department of energy savings, Govt. of India.

In order to make any Air Conditioner energy efficient, the manufacturers improve the design parameters that increase the airflow, increases the surface area of copper tubing for effective cooling and improving the working of the compressor.

Although, this increases the initial cost of the energy-efficient AC more than the normal 1-2 star AC.

But it subsequently improves the running cost of the AC which makes the payback faster.

And becomes more energy efficient.

The right size of AC for me

In broad terms, it depends on your room size.

In earlier times when there were no air conditioners.

People use ice blocks to cool their surroundings.

They derived a standard measurement of the cooling effect based on the amount of ice and the time.

1 ton of refrigeration means, the heat absorbed by 1 ton (907 kg) of ice at 0ᵒ C (32 ᵒF) to get it converted totally into the water in 24 hours.

The general thumb rule is the volume of your room in cubic ft determines the tonnage of the air conditioner.

• Volume = length x breadth x height

For example, 1000 cubic feet of a room requires 1 ton capacity of air conditioner.

However, in addition to room size, the other factors that can affect the tonnage of the air conditioner are:

• Latitude of your location
• Load in the room (number of persons in the room)
• Frequency of door opening and the size of the windows.
• Room ceiling is exposed to the sun or not
• Wall material

Understanding capacity in detail

How much heat an air conditioner can pump out of your room in 1 hour.

That defines its capacity.

It can be measured in 3 ways:

• Btu/hr
• Watts, and in
• Tons.

a) Btu/hr

1 Btu/hr is equivalent to 1055 joules of heat pumped out by the air-conditioner in 1 hour.

This energy is equivalent to burning a single matchstick.

But the matchstick lasts for a few seconds.

This means, that 1055 Joules of energy is released in a few seconds but in Btu/hr, the same joules are pumped out in 1 hour (3600 seconds).

Therefore, the intensity of energy is less in the latter case.

b) Watts

1 watt defines how much an air conditioner can pump out per second.

c) Ton

It is equivalent to the cooling effect provided by the 907 kg of ice over 24 hours.

The relation among the three units can be written as:

1 ton of cooling effect = 12000 Btu/hr = 3519 watts 

• 1.5 ton = 18000 Btu/hr
• 2 ton = 24000 Btu/hr
• 2.5 ton = 30,000 Btu/hr
• 3 ton = 36,000 Btu/hr

Different types of capacities

The normal air conditioner comes with 1 capacity (nominal capacity) as it cools at the fixed rate while the inverter ac has 3 types of capacity ratings.

• Minimum Capacity
• Nominal Capacity
• Maximum Capacity

This is because, the compressor of the inverter ac cools the room at varying rates, depending on the desired temperature level. The nominal capacity defines the cooling capacity under normal conditions.

While the minimum capacity means that the cooling rate is the slowest.

And the maximum capacity states the faster cooling rate.

Let us understand more clearly with the following table:

The ac nominal capacity is 1.04 ton (under normal conditions) and can go as low as 0.29 ton (minimum capacity) and as fast as 1.17 ton (maximum capacity).

Best temperature setting for your AC.

Power consumed by an AC

Cooling requires a lot of power.

Our Air Conditioners take power from the grid and in return cool our rooms.

Although, the power consumed by ac and the cooling capacity of the ac is measured in watts.

But these two are different.

It has a single value for normal ac and has 3 values (nominal, minimum, and maximum) for inverter ac.

I can see that the Energy Efficiency ratio is the maximum (12.65) when the air conditioner is cooling rate is the slowest.

While it is the lowest when the cooling rate is faster.

And under normal conditions, it has a fair value of 12.63 (almost near to the maximum value of 12.65).

(EER is the Energy Efficiency Ratio of Cooling capacity (in Btu/hr) to the power consumed in Watts).

Keeping the temperature around 25ᵒC or 78ᵒF is the optimum balance between energy savings and providing cooling comfort.

Any AC with an EER ratio > 9 is considered efficient.

The power consumption of any air conditioner is the product of operating voltage and the current withdrawn.

• In India, the operating voltage is 230 volts.
• In the USA, it is 120 volts.

Good practices to reduce the energy bill

• Keep the temperature at 25 degrees for the optimum working of the air conditioner.
• Clean the filter regularly
• Service your air conditioner every season.
• Keep the room close for the effective working of the air conditioner.
• Fix a time for running ac for its maximum utilization. Like having lunch together or sleeping in the same room to utilize it to the maximum extent.

Can I power my AC through Solar?

The power consumed by an air conditioner is directly related to your energy bill.

The more power consumed more you are going to pay for it. And the grid rates are escalating.

Therefore, in addition to looking for an energy-efficient air conditioner, we need an energy source that is affordable, clean, and smooth.

And Solar PV technology fits into it.

a) Units consumed by Air Conditioner

Let us take a 1.5-ton cooling capacity ac with an EER of 12.

 1.5 ton = 18000 Btu/hr

EER = Cooling Capacity (Btu/hr)/Power consumption

12 = 18000/Power Consumption

Power Consumption = 1500 watts or 1.5 units

So, every hour when the pump out 18000 Btu/hr heat out the room, it will consume 1.5 units of electricity.

Let’s share my energy consumption chart for the whole year:

b) Finding the panel size

January, February, March, November, and December are non- ac months.

Therefore, I’ll not include these months for sizing the solar panels.

The hours on the table are running of ac in the daytime when there is the sun in the sky.

For running ac at the night using solar, you need the battery back.

This adds extra cost to the solar power system.

I have the following information:

Peak Sun Hours = 5

1845 units consumed in 7 months or 210 days (1 month = 30 days)

Average units consumed per day = 1845/210

= 8.8 units or round it to 9 units per day.

I need a solar power system that can provide 9 units per day.

Size of solar panels = Multiplier to cover system losses x (units consumed/PSH)

Size of the solar panels = 1.4 x (9/5) = 2.5 kW

I need 2.5 kW solar panels to run my 1.5-ton ac to cover my daytime energy needs for 7 months.

Is my solar power system remains idle in the non-ac months of January, February, March, November, and December?

No, during this period you can power other electrical appliances such as LEDs, Fans, refrigerators, etc of your house.

It will continue to provide smooth electricity for decades.

c) The payback period

Payback period with 1.5-ton ac with EER of 12:

A 2.5 kW system (without battery backup) costs you Rs. 1,70,000/-

Read: What is the price of 5-kW solar power system in India?

This will save you around Rs. 26,000 per year.

Payback would be = Rs. 1,70,000/Rs. 26,000 = 6.5 years.

Solar Power system cost with the less efficient 1.5-ton ac:

In case you chose a 1.5-ton ac with EER of 9.

As the efficiency of the AC reduces, it will consume more power.

And we need a bigger system to run the air conditioner.

The percentage decrease in the efficiency {(12-9)/12 x100%} = 25%

Can be seen as an increase in the solar power system by the same percentage.

Read: Know the money you can save using solar in India

Common problems with AC

If properly maintained a modern air conditioner in India can last over 15 years.

However, there are common problems with ac that buyers face.

These are:

a) Leakage

Refrigerant leakage is the most common problem in ac.

The refrigerant is responsible for the cooling of the room.

As it takes away the heat from room air.

The refrigerant in ac is stored at high temperatures.

Therefore, the copper tubing in which it flows is under constant pressure.

Also, the humidity and other corrosive particles in the air make these piping weak with time.

This causes holes in the cooper tubing and refrigerant leaks out.

Therefore, look for ac with strong copper tubing to avoid frequent leaks.

b) Accumulation of dust in the filter

The filter on the front side of the ac unit filters the dust and allows clean air inside the unit.

With time, the dust gets accumulated over the filter and it gets choked.

Now, the compressor is working harder to take in the clean air for circulation.

This increases the temperature above the ideal operating conditions.

Making compressor switch ON/OFF frequently (normal ac) or working with faster capacity (inverter capacity).

This puts stress on the ac and more energy is consumed.

Therefore, clean the ac filter regularly.

c) AC is making noise

There are times when ac unit makes noise while running. This can be due to dis-balancing of the fan inside the unit.

Also, it can be due to the accumulation of dust on the blades of the fan. Call your technician for the cleaning of the unit.

d) AC swing not working

There are times when the swings do not work.

Either the swing motor is not working properly or your remote is not sending the signal to the PCB installed in the unit.

The other problems like the AC unit not starting with the remote or foul smell when you run the ac can be rectified by the technician.

All the above common problems with ac can be rectified when you service your ac regularly.

Top brands offer free service for 1 year on newly purchased ac units.

This can be extended further by paying the extra charges.

The best AC in India

The choice of the best air conditioners is based on the following parameters:

• Price
• Technology
• Noise level
• Air quality
• Star rating
• Warranty
• Service

1. LG 1.5 Ton 5 Star Inverter Split AC: The most silent air conditioner

This LG AC has a special EZ clean filter and stabilizer-free operation. The high

grooved copper coil makes it useful for long-term usage and low energy and low noise

performance.

Features include:

• Price – ₹66,990
• Type – Split
• Capacity – 1.5 tones
• Energy Rating – 5-star rating
• Condenser Coil – Copper
• Power Consumption – 818.81 units annually
• Noise Level – 31 dB
• Warranty – 1-year limited warranty
• Special Features – high-quality construction, extremely low noise and energy consumption, anti-bacterial dust filter

2. Daikin 0.8 Ton 3-star split AC: Best for small room

This powerful AC offers high-quality performance at an affordable price. Even with a 3-star energy rating, it consumes minimal energy at the optimum settings. Its unique feature is that it is compatible with eco-friendly refrigerant gas, so it will not harm the environment also.

Features include:

• Price – ₹27,200
• Type – Split
• Capacity – 0.8 tones
• Energy Rating – 3-star rating
• Condenser Coil – Copper
• Power Consumption – 594 units annually
• Noise Level – 28 dB
• Warranty – 1-year limited warranty of the product, one year on the condenser, and additional 5 years on the compressor
• Special Features – PM 2.5 filter, comparatively silent operation and compatible with eco-friendly refrigerant gas.

3. Bluestar 2-Ton 5-star inverter split AC: Fast cooling

This powerful AC uses precision cooling technology and offers features such as a dehumidifier, inverter operation, dust filter and eco function which enhances the user experience.

Features include:

• Price – ₹76,000
• Type – Split
• Capacity – 2 tones
• Energy Rating – 5-star rating
• Condenser Coil – Copper
• Power Consumption – 1087.24 units annually
• Noise Level – 49 dB
• Warranty – 1-year limited warranty on the product, one year on the condenser, and another 10 years on the compressor
• Special Features – Turbo cooling, smart climate control feature, dehumidifier, inverter compressor, dust filter.

4. Hitachi 2-Ton 3-star inverter split AC: Low power consumption

Even though it is a 2-ton AC, at its optimum settings, it hardly takes up energy as consumed by 1.5-ton AC. The topical cooling design keeps you cool even if it is not in its most power consuming setting. The inner grooved copper coil ensures quicker cooling.

Features include:

• Price – ₹41,999
• Type – Split
• Capacity – 2 tones
• Energy Rating – 3-star rating
• Condenser Coil – Copper
• Power Consumption – 1158.94 units annually
• Noise Level – 39 dB
• Warranty – 1-year limited warranty on the product, one year on condenser, and another 5 years on the compressor
• Special Features – extremely low power consumption for the cooling capacity size, soft dry, auto fan speed, super cool mode, fan mode, one-touch silent fan function.

5. Samsung 1.5 Ton 3-star inverter split AC: Most durable

This AC comes with an in-built voltage fluctuation protector and offers high durability copper condenser and extended warranty period.

Features include:

• Price – ₹48,990
• Type – Split
• Capacity – 1.5 tones
• Energy Rating – 5-star rating
• Condenser Coil – Copper
• Power Consumption – 1044.19 units annually
• Noise Level – 45 dB
• Warranty – 1-year comprehensive product warranty, 1year on the condenser, 10 years on the compressor, 1 year on PCB, and another 1 year on gas recharge
• Special Features – inverter compressor, dehumidifier, turbo cooling, high-density filter, auto clean, low power consumption even with the 3 star rating.

6. Voltas 1.4 Ton 3-star fixed speed split AC: Clean air

This AC offers most innovative features like the advanced air purification and multi-stage purification process which makes the environment extremely hygienic. Other powerful features are high ambient cooling, stabilizer-free operation, and the best anti-bacterial filter.

Features include:

• Price – ₹51,990
• Type – Split
• Capacity – 1.4 tones
• Energy Rating – 3-star rating
• Condenser Coil – Copper
• Power Consumption – 1101.55 units annually
• Noise Level – 45 dB
• Warranty – 1-year limited warranty on the product, and 4 years on the compressor
• Special Features – almost silent operation in large rooms, anti-bacterial filter, value for money product.

Best Window Air Conditioners

1. Voltas 1.5 Ton 5-star window AC
2. LG 1.5 Ton 5-star wi-fi inverter window AC
3. Blue star 0.8-Ton 4-star window AC
4. Carrier 1.5-Ton 4-star window AC
5. Hitachi 1-Ton 3-star window AC
6. Panasonic 1.5 Ton 3-star window AC

FAQ

1. What is the cooling capacity of AC?

How much heat your ac is pumping out per hour defines its cooling capacity.

An AC with higher tonnage has more cooling capacity than that of one with lower tonnage.

2. What is ISEER?

It is the Indian Seasonal Energy Efficiency Ratio.

It is the ratio of total annual amount of heat that an ac can pump out to the total energy consumed during the same period.

3. What is R-32 refrigerant in AC?

The refrigerant flows through the coil that connects all the parts of the AC unit.

It works as a heat exchanger.

It takes away the heat from the room and pumps outside with the help of other parts in the AC unit.

The R-32 refrigerant is gaining popularity.

Because it does the heat exchange more effectively than the other refrigerant such as R-22.

Also, it has less environmental impact compared to other refrigerants used in air conditioners.

4. Is a voltage stabilizer required for AC?

The normal ac that works on fixed voltage needs an external stabilizer for its optimum performance and protects it from damage.

Coming to the latest inverter air conditioners that work on varying speed come with built-in voltage stabilizer.

That can tolerate wide range of fluctuations in voltage, without the need of an external stabilizer.

If the voltage fluctuations in your area are within the operating range of the ac.

Then you don’t need a stabilizer.

But one cannot say about the fluctuations.

It can anytime go out of range may impact the performance or may damage your ac.

Therefore, to be on the safer side, it is advisable to have an external stabilizer for your ac unit.

But Samsung has models with an S-UTR compressor that eliminates the need for an external voltage stabilizer.

Buying Tip: Do check the operating voltage range of the in-built stabilizer of the AC.

Conclusion

Rapid industrialization, cutting down of trees, extensive use of fossil fuels has impacted our environment.

This has raised the average temperature of earth.

This is global warming.

If you are planning to buy an AC.

Then looking for high star-rating AC with R-32 refrigerant that has a lower global warming impact could be the right step.

Also, powering your ac unit using solar power is another step that can make your overall energy consumption environment friendly.