Air Conditioner buying tips

Air Conditioner – an inexpensive luxury :
Now it has become easy to purchase Air Conditioner, a ‘luxurious’ item, for a common man due to several reasons like:

• Lowered price of equipment due to technical advancement
• AC s are made energy efficient, lighter in weight with no or less noisy
• Installation of Air Conditioner is no longer a tedious job
• Maintenance cost of Air Conditioner is much lower now
• A comparative study of brands, prices and efficiency can be done online easily

Types of Air Conditioner:
Air Conditioners are available in many models like Window AC, Split AC, Cassette AC and floor standing AC. There price vary with their type, size, ability to provide comfort and features. Usually Window AC or Split AC is in use in India. The type of AC to be chosen also depends on the place of its installation.Size of Air Conditioner: Split Air Conditioners: Split air conditioners are also available in various sizes like 0.75ton, 1ton, 1.5ton 2ton etc. The size of AC should be according to the size of room where AC is to be installed. It is suitable to install a 1ton AC in the room of size 12ftx12ft or so. A smaller room will need the smaller AC and the bigger one will need accordingly a bigger AC.

Offers more flexibility on where to locate the outside component than wall models

• Can cool open-plan areas well
• Very quiet operation
• Attractive and aesthetic designs
• Good air distribution for ACs of same size

Wall or window model Air Conditioners: Wall or window models can be installed in a window or an external wall.

• Can cool single rooms well
• Smaller units can be plugged into existing power points
• Single Unit
• Require lesser upfront cost as installation is simple

Power efficiency of the Air Conditioner:
In today’s expensive power situations, electrical equipment should be power efficient. It is declared by the manufacturing companies by displaying its energy efficiency rating provided by BEE. Though an equipment having 5/5 (5 star) rating is the most efficient one but AC is rarely found in this rating. Air Conditioners with 4star or 3star rating are considered to best.
Cooling Capacity:
The cooling capacity defines the price of air conditioners. Most air conditioners are rated in BTU per hour (British thermal unit) or by tonnage. One ton is equal to 12,000 BTU per hour. The cooling capacity that you need would depend on factors.
Average ambient temperature:
Higher the average temperature of the outside air in the area where your house is located, the more will be the cooling capacity required.
Size of the room:
The cooling capacity required is proportional to the area of the room you wish to cool.
Number of people present:
The cooling capacity of an air conditioner also depends on the number of people present in the room. The more the people present, the higher will be the capacity required.
Exposure:
Direct exposure of any of the walls of your room to sunlight would lead to higher requirement in cooling capacity.
Proximity of your room to kitchen:
If the room is nearer to the kitchen the cooling capacity required would be higher.
The tonnage of the AC can be selected based on the chart below: 

Rooms Size (Sq ft)	Tonnage Capacity
Up to 90 sq ft	0.8 Ton
Up to 120 sq ft	1.0 Ton
Up to 180 sq ft	1.5 Ton
Up to 220 sq ft	2.0 Ton

Types of Compressors

The compressor is the air conditioner's most important component and is often called the heart of the refrigeration system. It helps in the cooling process, by circulating the refrigerant through all the refrigeration parts. There are three types of compressors - reciprocating, rotary and scroll either of which can be used in split ACs.

1. Reciprocating compressor: It compresses the air by sliding the piston over the cylinder. Air conditioners fitted with a reciprocating compressor are generally less expensive and not as efficient or silent as the ones fitted with a rotary compressor. These are good for high duty cycles e.g. with higher capacity cooling ACs which need to be run for longer times.
2. Rotary compressor: This is a superior type of a compressor over the conventional reciprocating type. It compresses air by centrifugal action of high-speed impeller in a confined space. This method reduces the loss in pressure of the refrigerator gas. Rotary compressors are more compact, operate quietly, built for continuous operation and typically see less maintenance. The down side is the initial costs are higher. For less than 3 ton these are good options as they don't need high duty cycle and have better energy ratings. Rotary technology, though dominant in the Asian market for close to three decades due to its low cost, is new to India.
3. Scroll compressor: Scroll compressors have a wide operating voltage, economical running and low sound and vibration as compared to reciprocating and rotary compressors. Scroll compressors are generally available in ACs with cooling capacity above 2.5 tonnes. Rotary and Scroll compressors are not repairable once the failure occurs out of warranty period. Reciprocating compressors are reparable - mostly by respective compressor manufacturers in India.

AC Installation: 

• Make sure that you install the unit in an area that provides good ventilation. The air conditioner must not be blocked by any obstacle affecting the air flow near the air inlet and air outlet.
• Make sure that you install the unit in an area which can endure the weight and vibration of the unit.
• Make sure that you install the unit away from heat or vapor.
• Make sure that you install the unit in an area where the cold air can evenly spread in a room.
• Make sure that you install the unit in an area which provides easy drainage for condensed water.
• Make sure that you install the unit in an area not exposed to rain or direct sunlight. (Install a separate sunblind if exposed to direct sunlight.)

Do not install the unit in an area subjected to noise or vibration amplification which may affect your neighbour.