Tuesday, February 21, 2012

About Split AC


Split ACs are becoming a popular choice in most homes these days. Their sleek exterior, flexibility in mounting locations, as well as quiet performance has found many a fan. Previously split AC was an appliance for office or a Rich man's gadget but today, it has found its way into the smaller middle class homes as well. Depending on the size of your room and the number of people occupying it you can decide on the tonnage capacity of the split.

Here are some Key factors to be considered before buying investing in a split AC.
BUDGET
You may already have a budget in mind as to how much you would like to spend. Split Air Conditioners range between Rs 14,500 to Rs 2,75,000. The size and features affect the price.
TYPE OF SPLIT AC
Wall mounted

These are also known as high wall mounted. This is mainly used in rooms where the ducts cannot be concealed, and is generally preferred for small rooms where it is easy to cool the air uniformly. Wall mounted split ACs start from Rs 14,500 onwards.
Floor mounted


Floor Mounted also known as tower or vertical split ACs are generally used when you do not have space or do not want to mount an AC in your wall. Floor mounted splits start from Rs 32,000 onwards.
Ceiling mounted


Ceiling mounted ACs also known as Cassette type split air conditioners cool the room uniformly from their vantage point at the ceiling. These are useful if you don't have space for a wall mounted or a floor mounted air conditioner. Prices for these start from Rs 55,000 onwards.


Multi Split ACs
Multi-splits are multiple split ACs connected to one unit. With a multi-split option, tow indoor units can be installed with one outdoor unit.

The indoor units can be used individually or at the same time as needed. If both the units are used then the capacity of the units will be divied. The condenser and fan of the outdoor unit is controlled based on the control signals from indoor units.

Advantages of multi-split ACs
  • Saves installation space
  • Can be used individually or simultaneously
  • Independent control
  • Compact Design
  • Good EER
  • Saves on running costs
  • Convenient and economical
Disadvantages of multi-split ACs
·  Expensive compared to a single unit split AC
·  Limited range of capacities and models
·  More prone to leakage as number of indoor units increases

Most of the units today like LG, Bluestar or Hitachi offer 1.0 T, 1.5 T or 2.0 T capacity for each indoor unit.
COOLING CAPACITY
The cooling capacity defines the price of a split air conditioner. 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 such as:

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

You can also check AC Tonnage Calculator from LG

NOISE
Indoor units that do not produce much noise are better as else these can be a big disturbance.
SPLIT AC PRICE AND BUDGET
You should take care to narrow down on the appropriate split ac by looking at the product design, quality and its performance. Also, consider the installation cost, running costs like power and maintenance while buying your AC.
ENERGY EFFICIENCY RATING
The ratio of air conditioner's cooling capacity to its power consumption is the unit's (EER). A system with higher EER is good. Though these models are expensive while buying, they save money in the long run by consuming less energy.
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.
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.
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.
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.