How to make your Window Air Conditioner more Efficient

Your window air conditioner is an appliance that requires very little TLC to keep it at its maximum efficiency. Most of the following suggestions are simple and only need some common sense to apply. So if you want to get the most ‘bang for your buck’ from your window air conditioner then read on. 

1 … Clean Filter
This is an obvious suggestion, but also a very important one. Once the air conditioner is installed cleaning the filter is something many of us simply forget to do. Remove and clean the filter every week during the operating season. Also brush off any accumulated debris near the front of the air conditioner. If required soak filter in few inches of hot water to which has been added a small amount of laundry detergent. Rinse thoroughly and allow to dry before reinstalling into the air conditioner. 

Remember that although the filter captures debris from the room its primary job is to protect the cooling coil located at the front of the machine. Any dirt or debris entering here will coat the coils and drastically reduce its ability to pick up room heat, thereby lowering the cooling effect. Therefore keep the filter clean to keep up the efficiency. 

2 … Properly Levelled
Level is not a correct description when referring to window air conditioners. In fact they must be installed so that the rear of the machine is approximately 1-inch lower than the front. This slope allows water collected by the cooling coil to flow through channels in the base and then into the rear of the air conditioner. Once at the rear the moisture is allowed to drop out of the base onto the ground. Since removal of the moisture from the air within the air conditioned room is what produces most of the cooling effect, proper installation becomes critical. 

Also, try not to exceed the 1-inch drop of the rear of the air conditioner. Water collecting in the base must not be allowed to run out too quickly because it’s used to cool down the condenser coil (the radiator-like device) at the rear of the machine. As the fan blade turns water from the base is picked up and thrown onto the hot condenser. This will lower the condensers surface temperature and help it to transfer the maximum amount of heat. Therefore proper leveling of the air conditioner has this secondary purpose that also results in more efficient operation. 

One of the reasons people may lower the rear too much is in an attempt to eliminate the splashing noise made by the fan blade as it hits the water accumulating in the base. This is because people will often interpret an unusual noise as something malfunctioning. Therefore they lower the rear of the air conditioner and force the water out of the air conditioners base until the noise ceases. Never do this – the splashing noise (generally heard during start-up) is simply an indication that the air conditioner is working well. 

3… Raise Thermostat
Again, this one is common sense. If operated at a warmer temperature the air conditioners overall run time will be less, resulting in less electricity consumed. 

4 … Ambient Temperature
Be aware that a strange phenomena can occur whenever we spend a lot of time inside an air-conditioned room. Over a period of weeks your body adapts to this temperature until your brain begin to think of the temperature within the air conditioner room as normal. Unfortunately, as the cooling season continues this can result in you wanting to operate the air conditioner at an increasingly colder temperature because you feel the room is too warm, even though visitors find it too cold. Therefore use a room thermometer as your guide to maintaining the room temperature, rather than how your body feels. This method will keep you from making unnecessary adjustments that will increase run time and lower efficiency.

5 … Turn Off
Turn your air conditioner off whenever you’re not occupying the room for an extended period. There is a common fallacy that setting the thermostat to minimum, or to the 'fan-only' position, and allowing the air conditioner to operate is more energy efficient than turning it off. This is false. Therefore if you wish to raise efficiency turn the air conditioner off whenever you leave the room for a period of time. Even if the room becomes very warm while you’re away it will only take the air conditioner a few minutes to cool it down again once it’s restarted. 

6 … Turn off during bad weather
Modern window air conditioners often have electronic touch pads or computers. Both are prone to failure if the electricity goes off during a thunder or lightning storm. Also, momentary fluctuations in the electrical supply can result in power spikes that harm delicate electronic components. Since erratic or false readings from these components can affect efficiency we always suggest turning off (or even unplugging) window air conditioners during a storm. 

7 … Watering the condenser
I have had many inquiries about this practise therefore I feel I should respond to them. It has been suggested to me that attaching a lawn hose to the rear of the air conditioner and constantly running water across the condenser would make the air conditioner more efficient. The theory is that since the water is cooling the hot condenser this will draw away its heat and make the air conditioner more efficient. Unfortunately the theory and results are often contrary to one another. The cost (and waste) of water used by this method should prohibit it from ever being considered. Plus, running water through electrical machinery is a disastrous idea that will only result in someone getting injured. Therefore never using this method is itself energy efficient.

8 … Sunlight into room
Direct sunlight through your windows will warm up the room making the air conditioner run longer and consequently lower its efficiency. The simple act of closing drapes or lowering blinds can help cure this problem and give the air conditioners efficiency a corresponding increase. 

9 … Shading rear of air conditioner
Natural shading occurs on the northern or eastern sides of your house and will result in a more efficient air conditioner. This is something to consider when deciding which window opening to place it into. It’s something that costs nothing and yet most people don’t even consider how positively proper placement can contribute to efficiency. Direct sunlight striking the rear of your air conditioner will make it work harder by overheating the already hot condenser coil. Therefore shading the rear area allows the condenser to give off its heat quicker which will raise its efficiency. Other authors suggest the addition of an awning or planting a tree to shade the rear of the air conditioner. Shading your air conditioner by these methods is usually not practical because the money spent will not be recouped by any resulting increase in efficiency.

 By Donald Grummett
 

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