Air Conditioner AC, HVAC, Air Conditioning Units, Portable Air Conditioners, Window Air Conditioner, Split Air Conditioner

It is very easy to buy A.C. if the buyer knows the functioning of A.C. The technology of A.C. and refrigerator is almost same. The function of air conditioning unit to remove both heat and humidity. In the functioning of A.C. evaporator coil, condenser coil, refrigerant and fan have main functions. An evaporator coil cools the air inside where as condenser exhaust warm air out side. Air conditioners cool by passing air over refrigerant coils that have fins that look like an automobile radiator. The fan blows the cool air in to the room.

There are two different kinds of room air conditioning systems are available in the market. One is the Window air conditioner, and other is Split air conditioner.

The difference between them is that a window air conditioner is the big box can be fixing either in window or in a space left for this purpose in the outer wall, while a split air conditioner system hooks onto the wall. It really depends on whether you are looking at cooling a room or the entire house. Window air conditioner or room air conditioner is the best choice for a house where small area to cool in the summer i.e. one or two rooms. It is portable and can be shifted easily at the time of transfer or changing the house. It will cost less initially and it will cost less to operate in the long run. But if you have a room where there is no window or for some reason the air conditioner cannot be fitted on the window; or you need to keep the noise levels low, then you might want to consider getting a split air conditioning system, although this can cost you little more.

The efficiency of room air conditioner depends upon the selection of proper size of air conditioner. If one, install too large unit, than it is not able to remove humidity and less effective than the correct size. Also, remember that larger units cost more and use additional energy .If one, install small size air conditioner, than it will not be able to give proper cooling. Running a proper size unit for a longer period will use less energy to cool a room than running a larger unit. Improper installation also reduces the efficiency of room air conditioner.

The efficiency of room air conditioner depends on:

Filters that need to be cleaned periodically. For easy maintenance, choose one that has a slide-out filter. Keeping the filter clean will save you energy and money.
Today's energy-efficient models can also handle larger areas with ease.
The way to choosing the right air conditioner is matching the proper unit to the space you want to cool.
There are many factors to be consider when choosing a room AC that is number of windows, number of people in the room, which direction the room is facing, ceiling height, etc.

If you have decided to buy a unit air conditioner, the first thing you need:

Select the capacity of the air conditioner required for the room. A thumb rule is that about 100 sq feet floor area needs one ton of cooling capacity.An expert will be able to advise more correctly after site inspection.
You also need to consider the surroundings, whether the room is exposed to sunlight or shaded.
The air conditioner needs fresh air outside the room to work efficiently. There should not be any blockage at the back and no source of heat.
The moisture from the room, collected in the form of water needs to be properly drained out.
Getting the right capacity of air conditioner, calculated based on the area to be cooled, is also important.
If an air conditioner is installed in a curving hallway or in corner, it will not cool the other end of the room, because cool air does not travel around corners.

Measure the room and window:

Before buying an air conditioner, it is important to measure room size carefully in which air conditioner is to be installed. Because 90 percent of your decision-making process involves the size of the room that you want to keep, cool. So measure the entire room properly to get the right unit. Write down the height, width and length of the room. After room measurement, take the size of window in which unit will be installed. Some brands do not list the precise dimensions of their air conditioners on the units. Therefore, it is necessary to know the accurate size of the unit and window which unit will be installed. It is very embarrassing when the unit does not fit in the window of the room and the owner will have to spend the time and extra money for installation of the air conditioner.The cooling capacity of room air conditioners is measured in BTU's or British Thermal Units, per hour.

Select the proper unit according to your room size with the help of table given below.

Area to cool (in square feet)	Size of Air Conditioner (in BTU's)
100 to 150	5,000
150 to 250	6,000
250 to 300	7,000
300 to 350	8,000
350 to 400	9,000
400 to 450	10,000
450 to 550	12,000
550 to 700	14,000
700 to 1,000	18,000
1,000 to 1,400	24,000

Suggestions for correct size air conditioner :

1. If the room is heavily shaded, you can reduce the BTU capacity by 10%
2. If the room is very sunny, you should increase the BTU capacity by 10%
3. If more than 2 people regularly occupy the room, add 600 Btu for each additional person
4. If the unit is for a kitchen, increase the capacity by 4,000 Btu/Hr.

Additional Recommendations :

In addition to size, consider an air conditioner's Energy Efficiency Ratio. The Energy Efficiency Ratio approximates the unit's operating cost as compared to similar models. If the Energy Efficiency Ratio is high than it’s operation cost will be less.

Before you get ready for purchasing, one should check out Consumer Reports or some other product-rating publication so you are able to purchase the unit from the recommended models. One should not purchase a no-name brand without researching it, or you would not know the quality and durability of air conditioner. In case lack of knowledge or you are not interested in hunting down brand ratings, then purchase a brand you already trust or well known brand of the market.

Some things to consider when purchasing air conditioner:

1. Warranty: At the time of purchasing, see product-rating publication and most important feature of unit. Be sure that air conditioner comes with at least a 1-year warranty that covers labor and parts on the entire unit. In case of break down, you can return it and get a new one or send it in to be serviced, free of charge. Some stores even offer an extended warranty plan (typically covering 4 to 5 years instead of just 1) with an extra fee.

2. Temperature Range: While purchasing the unit sees the temperature range, if it spans less than 20 degrees (e.g. 68 to 86 degrees F), it may not be sufficient for your needs, particularly if you live in a hot climate.

3. Temperature Increments: Be sure that the temperature can be incremented in notches of 1 to 2 degrees F. This allows for greater precision and prevents electricity waste.

4. Sleep Setting / Energy Saver Settings: While purchasing the unit sees that air conditioner have a sleep setting or energy saver switch so that, at night when you are sleeping, the air conditioner slows the cooling process to a minimum, saving money and energy.

5. Slide-out Filter: Every unit air conditioner has a filter that must be cleaned. While purchasing the unit, get a slide-out filter air conditioner, not a frame-enclosed one and save yourself an immense hassle. The slide-out filters are easy to remove and re-install.

6. Fan Speed Settings: While purchasing the unit sees that how many fan speeds are offered on the unit? The more settings available, the better the energy saving will be (and the more choices you have).

7. Installation: Make sure your unit air conditioner comes with installation directions. There is nothing worse than getting the thing home and suddenly realizing you have no idea what you should do with it. If you have any questions about the installation process, definitely ask a store employee for advice before you leave and attempt it yourself. Some air conditioners require that you drill holes into walls or bricks. It would be nice to be aware of such things in advance.

8. Check the Power Supply: While purchasing the unit sees the kind of plug fixed with the unit and also check the kind of plug fixed on the wall. Make sure the circuit can handle the operation of the unit. Smaller ones work with a standard 115-volt outlet. Larger 115-volt units may need a dedicated circuit. The largest AC units require a 230/208-volt circuit.

SAFETY NOTE:

When adding a new circuit, always hire a licensed electrician to connect the power to the panel box. Also, make sure your air conditioner is properly grounded. Never alter a plug to fit your outlet.
Weight: An AC unit can easily weigh over 50kg. Get some help when carrying and installing the unit.
Noise: Although new units of air conditioner are much quieter than older models but be prepared for some additional noise in the room.
Installation: Follow the manufacturer’s instructions carefully when installing a window unit. It is essential that the unit be stable for safety reasons. It is also essential that the unit be tightly sealed to keep the cool air inside. Apply weather-stripping as needed to prevent air flow around the unit. Put the AC in shaded window, which provides more cooling.

Air Conditioner AC: Tips before buying Air Conditioners