It is not a rocket science to choose an AC. There are primarily two types of ACs one gets to choose for a residential area in India.
Window AC - typically supporting a smaller room, cannot equally cool all areas of the room but cheaper
Split AC - Looks elegant, can equally cool all areas of the room, but more expensive, very less noise and is preferable for larger rooms
The most important qualifying things are:-
The look and feel (very important for Split AC especially)
Size of the airconditioner (especially for the Window AC’s)
The power consumption (Amps drawn and the EER, Higher the EER and less Amps drawn is best)
Warranty period
After sales service quality
Noise level (in decibels or db, higher the db more noisier it gets, a rating of 40 db and below is excellent as a quiet room itself has a 40 db level noise factor)
Price (should be the last, as it will lead to bias in your judgement and can eliminate the worthy contender). Ofcourse for some this is the holy grail and nothing else matters.
The following aspects are important in arriving at the appropriate AC for your room. All AC’s come with tonnage capacity. Some start as low as 0.75 to 4.00. The lower the tonnage, lesser the cooling capacity.
Typically the tonnage is arrived at estimating the heat load for the room
All of the following categories will influence the tonnage required.
The Length, Breadth and Height of your room or office.
The false ceiling height, if you have a false ceiling.
The type of flooring (wood, marble or any other)
Typical humidity levels in your area
Minimum and maximum temperatures of your area
Which floor you might be living if in an apartment complex (higher the floor, more heat)
The Length of each wall which is exposed to the sun, and its orientation.
The square feet area (length x height) of partitions (examples are, walls which are not exposed to the sun, and are not adjacent to air-conditioned areas, such as toilet walls, staircases, passages and kitchens).
The size of each window (length, height) in each exposed wall, and the number of windows.
Area of the floor in square feet, if the floor below is non-air conditioned.
The number of persons occupying the space most of the time.
The lighting load in watts per sqft. (Total number of tubelights x 40 watts / square feet floor area, or use 1.5 watts per square foot as an average figure.)
The number of PCs / servers / Printers / music system, if any.
The capacity of the UPS in KVA, if you have a UPS.
Typically AC’s come with 1 Year warranty.
If you are interested in Annual maintenance after warranty expiry, check what does it cover?
If it covers just cleaning filters and a quarterly checkup, then forget it.
Does it cover fan motor and compressor failure (compressor manufacturers typically give 2 year warranty, hence an AC manufacturer does not have to spend any money to replace it except the labour involved in changing the compressor) and gas leaks. These are the 3 most costly repairs which an owner will encounter.
Since prices of AC’s are falling all the time, it might be worthwhile to buy a new AC than have an Annual maintenance contract every year.
Only some AC manufacturers manufacture their own compressors, most of them rely on third party compressor manufacturers (Shriram-Tecumseh, Kirloskar etc).
Also definitely get it right the electrical capacity required to sustain an AC with all other devices operating at the same time. Many times AC’s trip because of it. Many a time an owner installs an AC in a room when there is no heat source but later adds all kinds of stuff without checking whether the circuitry can handle it and then they start blaming the AC manufacturer.
For some split AC’s remote control has to be pointed straight at the AC at a certain angle, check if the remote control works at any angle from any corner of the room. Its a pet peeve especially in the night when you are not in the mood to correctly position it for the remote to work.
In split AC environment, make sure you get the head load calculations correctly, else water starts dripping from your AC as the AC has to work extra hard to cool the room, and this also would lead to wear and tear of the compressor and it eventually fails as well.
Not every room is designed for AC installation in mind. Those are extra charges. The installation costs vary depending on the piping length, whether they have to make holes in concrete walls for the pipe to go, and the difficulty in laying out at a site. For window AC’s in particular the customer’s window size may not fit into the model of the manufacturer.
Have the AC manufacturer local branch service manager’s name and phoine number (not the dealer) as well as the National customer care manager’s information handy for any shoddy service reporting. Mind you the national Customer care individuals really do not want unhappy customers.
Did I say a Voltage stabilizer is a must for Window AC’s particularly as they are suspectible for damage because of extreme fluctuations.
If you are looking for a quick and dirty route try this quick purchase option:
For every 100-120 square footage of area, you can safely go with 1 Ton AC.
If you want to go the longer purchase route try this option:
Invite 3 separate manufacturers/dealers (ones you think resonate well with you) to your place, ask them to provide you detailed heat load calculation sheet which will give you the tonnage they recommend (higher the tonnage the more expensive the AC gets). Someone recommending higher tonnage does not mean they are wrong.
Talk to any references they have in your area. You can eliminate some contenders right there. Invite more manufacturers to recommend their offerings.
Only then ask to provide prices and ask each of them to explain why there is a discrepancy in certain things.
Ask for any discounts if applicable.
For best service from a dealer, allow them to make some money and they will sure remember you more and serve you more promptly in terms of need.
For Window AC’s for example, AC manufacturer’s price to a dealer is 15, 000, dealer’s upward ceiling sale price is 18-19, 000. Any discounts you will get will hit the commission the dealer gets (3-4 grand). The lesser the commission they get, more unhappy they are and less prompt they are likely to be with you when your AC fails on a sweltering day.