Are you in the market for a new air conditioner? Have you been considering a room air conditioner instead of a central air conditioner but aren’t sure what you should be looking for? Purchasing an air conditioner of any type should be researched before hand simply due to the amount of electricity your air conditioner could potentially use. If you purchase the wrong unit you may end up with extremely large monthly electric bills and inefficient cooling.
As a consumer you definitely want to find the best performing unit for you. You want to find a unit which is very energy efficient because not only will it save you money in the long run, it’s better for the environment as well. Energy efficiency is about making the best or most efficient use of energy in order to achieve a given level of comfort and convenience.
What is a Room Air Conditioner?
A room air conditioner is an air conditioning system designed to cool a room or rooms instead of the entire house. Do you live in a smaller home, townhouse, condo or even apartment? Would you prefer or do you require a non-permaneant air conditioning installation? If you answered yes then a room air conditioner may be a good matched for you. In comparison to central air conditioners, room air conditioners are dramatically less expensive to operate – even though they are often less efficient.
While central air conditioners often need higher voltage connections a room air conditioner can often be plugged into any 15- or 20-amp, 115-volt household circuit. If you have a larger room air conditioner you may need a dedicated 115 volt-circuit. In only the most extreme cases will you ever need a dedicated 230-volt circuit.
Room air conditioners are often vented or window mounted so they can effectively expel hot air out. Be wary of any room air conditioner that does not offer proper ventilation.
How are Room Air Conditioners Rated?
If you are familiar with central air conditioners you may be already familiar with the SEER or Seasonal Energy Efficiency Ratio. Room air conditioners are rated not on in SEER but rather in EER or Energy Efficiency Ratio. The EER of a given room air conditioner is calculated by dividing the cooling capacity in British Thermal Units (BTU) per hour by the power input in watts. You can find room air conditioners offering a range of cooling powers from 5,500 BTU per hour to 14,000 BTU per hour.
While the national appliance standard requires that any room air conditioner built after 1990 to have an EER of 8.0 or greater, and the latest Energy Star standards require in some cases an EER of 10.7 or greater I support the American Council for an Energy-Efficient Economy’s (ACEEE) recommendations. The ACEEE recommends at least an EER of 11.6. Why? This will guarantee your unit is energy efficient throughout the year and when it is needed most – the hottest summer months.
Selecting a Room Air Conditioner
Once you’ve decided to purchase a room air conditioner make sure you look for the Energy Star label. If every room air conditioner sold in the U.S. were Energy Star qualified, we could prevent 1.2 billion pounds of greenhouse gas emissions to put that into perspective that is equivalent to the emissions from 100,000 cars. Energy Star room air conditioners use at least 10% less energy than conventional models.
In the room air conditioner game Energy Star isn’t the only certification to be looking for. You should also look for Association of Home Appliance Manufacturers or AHAM Certified units. Why? AHAM Certified room air conditioners have their EER ratings verified by an independent laboratory.
Getting the Right Size
Room air conditioners like all air conditioning units are rated by the number of British Thermal Units (BTU) of heat they can remove per hour. Another common way of rating air conditioners is by the “ton,” some example are 5,500 BTU per hour or 14,000 BTU per hour.
Getting the right size room air conditioner for your application is crucial. If you get the wrong size you can easily waste large volumes of electricity. The size of your air conditioner depends upon:
How large is your home and how many do you have?
How much shade do you have? Do you have shade on your home’s windows, walls, and roof?
Are the ceilings and walls of your home insulated properly?
Do you have air leaks?
How much heat do you, the occupants, and appliances generate?
Remember the key to any air conditioners efficiency and performance depend on you properly matching the size of the AC unit to your specific application.
If you find this a bit confusing then you can always use the free AHAM tool. AHAM offers a handy online tool which can help you calculate your air conditioner (or evaporative cooler) needs.