Each air conditioner has an energy efficiency rating that lists how many BTU's per hour are used for each watt of power it draws. For room air conditioners , this rating is the Energy Efficiency Ratio, or EER. For central air conditioners, this rating is the Seasonal Energy Efficiency Ratio, or SEER. These ratings are posted on an Energy Guide Label, which must be attached in a visible place on all new air conditioners. Many AC manufacturers are voluntary participants in the Energy Star labeling program. Energy Star labeled appliances indicate that high EER and SEER ratings. The air conditioner EER is its British thermal units (BTU) rating over its wattage. For example, if a 10,000-BTU air conditioner consumes 1,200 watts, its rating is 8.3 (10,000 BTU/1,200 watts). The higher the rating is, the more efficient the air conditioning unit is. However, a higher rating is usually accompanied by a higher price. Let's say that you are given a choice between two 10,000 BTU air conditioning units.

One has an EER of 8.3 and consumes 1,200 watts, and the other has an EER of 10 and consumes 1,000 watts. Let's also say that the price difference is $100. To calculate what the payback period is on the more expensive unit, you need to know: Let's also say that you plan to use a room AC in the summer (approximately five months a year, depending on where you live) and it will be operating around eight hours a day. Say that the cost of a kilowatt-hour in your area is approximately $0.10. buy window unit air conditionerThe difference in energy consumption between the two units is 200 watts, which means that every five hours, the less expensive unit will consume 1 additional kWh (and therefore $0.10 more) than the more expensive unit. how much does an ac unit motor costAssuming that there are 30 days in a month, you find that during the summer you are operating the air conditioner: 5 mo. x 30 days/mo. x 8 hr/day = 1200 hours [(1200 hrs x 200 watts) / (1000 watts/kW)] x $0.10/kWh = $24.00 Since the more expensive unit costs approximately $100 more, this means that it will take about four years for the more expensive unit to break even. gas heating and air conditioning units prices

Not all BTU ratings can be trusted. Just because the BTU's are stated to be high on specific models, this does not mean it is necessarily true. Some manufacturers will exaggerate the BTU's on units to raise the possibility of selling them and others will be more conservative to cause lower EER ratings, so keep in mind that a low room air conditioner EER may be misleading. It is best not to allow the energy rating to be your only criteria for choosing an air conditioning unit. Research the unit you are considering for your home and you will be happier with your purchase. Here you'll find a helpful Portable Air Conditioner Buying Guide . Products with a higher EER rating can save consumers money in the long run. In places like offices and businesses, where appliances are constantly running, ratings can translate into huge savings over a short period of time. Portable ACs can be used in both the home and the office, including larger commercial settings, to ensure both home and business owners engage in energy efficient cooling .

A small, portable generator can power a window AC unit if it has the right wattage rating. Any window air conditioning unit can be powered by a generator. However, you may not be able to power many other appliances plus an AC window unit, depending on the size of the generator. Wattage is the primary unit of measurement used to determine how much a generator can handle. If you are considering purchasing a generator to power a window AC unit and additional appliances, you need to do basic math and planning to determine if the generator you choose is sufficient. Wattage Wattage (W) is the basic unit of measurement for electric power. It is defined as amperage (current or electrical flow) multiplied by voltage (electric potential). All appliances that plug into a standard duplex receptacle in the United States operate on a nominal 120 volts (V). The actual volts present at the outlet depends on a number of factors, including the electrical utility, and the length and size of the cable feeding the outlet.

However, you can reasonably expect that a properly installed duplex receptacle on a 120-V circuit has between 110 and 125 volts present. Amperage (A) varies from unit to unit. Typical Window Unit Wattage Window AC units have two watt ratings: starting wattage and running wattage. Starting wattage is higher because as the machine starts up and the motor begins to turn, amperage spikes as the motor draws higher current to overcome inertia and starting friction. A typical starting wattage for a window unit is 2200. Once the motor is running steadily, the amperage drops and the wattage usually is around 1500. Your unit may have different ratings. Examine the nameplate or the specifications in the manual to determine how much power your AC unit uses. Generators There are generators for just about any situation. The smallest generators are portable gas-powered units. The largest industrial-size generators can power a whole facility. A homeowner is likely to have either a small, portable generator or a whole-house generator.

Electricians generally install a generator, which is wired to a sub-panel or the main panel, depending on its size and specifications. Connecting your generator to an electrical panel allows for more efficient and safer power distribution throughout a house. Generator Wattage Generators are rated according to the maximum wattage they can handle. A typical portable generator for emergency use by a homeowner might be rated 4000 to 7500 W. Whole-house standby models typically are rated 25,000 W or higher. If you are considering purchasing a generator, deciding what size to buy is not as simple as adding up the watts of the appliances you'll use. Judicious power management strategies can help maximize the potential of your generator. References Honda: Wattage Estimation GuideNorthern Tool + Equipment: Generators Buyer's Guide Photo Credits Stockbyte/Stockbyte/Getty Images Suggest a Correction Reconditioned (1 from $ 83.93) Kenmore 6,000-BTU Room Air Conditioner Window Unit - Simple and Quiet Operation It’s easy to keep your cool when the temperature rises with the 6000 BTU Kenmore room air conditioner window unit 86052 .