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.
- 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.