Air conditioners start humming as soon as the weather gets hot delivering lower indoor temperatures and an escape from both heat and humidity. But while a cool home can be a welcome refuge from sultry temperatures, many homeowners pay a steep price for the comfort. In fact, Americans spend as much as half their energy bills to cool their homes, according to the U.S. Environmental Protection Agency (EPA).
Air conditioning efficiency is the result of year-round efforts, from pre-season maintenance of your system to smart improvements inside and outside of your home. Take time now to consider the following air conditioning efficiency checklist so that your family is comfortable and your utility bills are manageable through the warmest days of the year.
Schedule an annual air conditioning system tune-up
If you are lucky enough to have a central air conditioning system, now is the time to have it serviced. Central air conditioners work by using a chemical refrigerant, like Freon, to soak up heat inside your house and then transfer that heat to the exterior.
Central air conditioning systems must be in tip top shape for cooling a house efficiently. When properly working, the system should produce a temperature “differential” of 15 to 20 degrees, between return and supply air. This means that if the air being drawn into the system is 75 degrees, the air coming out should be at least 60 degrees. If it’s not, your air conditioner is probably low on refrigerant and you are wasting electricity.
Aside from lowering cooling costs, a properly maintained air conditioner prevents future problems. Home Performance with ENERGY STAR contractors who are trained cooling specialists can perform annual pre-season check-ups to ensure that a central air conditioning system is running as efficiently as possible.
A trained technician will check thermostat settings, lubricate all moving parts, inspect the condensate drain, check system controls for safety, clean condenser coils, check refrigerant pressures, and clean and adjust blower components for proper system airflow. Contractors will also show homeowners how to inspect, clean, and change air filters monthly. A dirty filter causes higher energy costs and can damage equipment. Filters in room air conditioners should also be changed monthly.
Even after servicing, make sure your central air conditioning system stays in shape by changing the filter at least once per month. At less than a dollar a piece, a clean filter can save you thousands on repairs by keeping the central air conditioning system free of clogs that can cause the compressor to break down.
Shade the air conditioning compressor
An air conditioner operating in the shade uses as much as 10 percent less electricity than the same one operating in the sun. Plant trees or shrubs to shade air conditioning units but be careful not to block its airflow. Compressors need at least a one-foot distance away from all sides of the unit.
Seal air conditioning ductwork
Up to 20 percent of the cool air your system generates can leak out through poorly sealed and insulated ductwork, so take time now to eliminate those escape routes. Use duct sealant (mastic) or metal-backed tape (never duct tape, as it doesn’t have the required staying power) to seal all seams and connections, and then follow with an insulation wrap.
Change HVAC filters regularly
Check and change filters once a month or more during AC season. A dirty filter makes your system work harder by slowing down air flow, and also wastes energy and threatens components with dirt and dust buildup.
Install a programmable thermostat
Programming air conditioning according to your away-from-home schedules yields significant savings while keeping you and your family comfortable during at-home hours.
A home doesn’t need to be chilled all day, day in and day out, to be comfortable in the summer. Save energy and money by using an ENERGY STAR qualified programmable thermostat. The thermostat allows homeowners to preset temperatures to automatically adjust to a more comfortable temperature when they are home.
Know when to upgrade central AC
If your air conditioner is over 10 years old, it may be due for replacement with an Energy Star qualified model. As you shop, remember that new equipment needs to be compatible with the rest of your HVAC suite in order to be efficient, and other components may also require replacement if they’re of a certain age.
The EPA labels the most efficient central air conditioning systems with the ENERGY STAR. These systems use up to 25 percent less energy than a standard new model. However, if your current a air conditioner is more than 10 years old, a new ENERGY STAR qualified air conditioner will use up to 40 percent less energy than the old model.
Choose and install the right room air conditioner
The best and most efficient room air conditioning comes from a unit that’s perfectly sized to the space and properly installed. Energy Star once again comes to the rescue with a collection of qualified room air conditioners that use 10 percent less energy than conventional models and can be selected with help from Energy Star’s room AC sizing guidelines.
For added energy efficiency, install your unit on the shadiest side of the house and select a model with easy-to-clean filters and controls such as a digital readout for the thermostat setting and a built-in timer.
Unlike central systems, window air conditioners don’t need to be serviced each year. The installation however, can make a big difference in how well the window air conditioner unit runs and how long it lasts. When setting a unit in the window, make sure it pitches slightly downward, towards the exterior, so that condensation trapped inside the window air conditioner unit will run out before it causes rust.
Next, make sure the gap between the half open window and the window frame is filled with foam insulation. This keeps both warm air and insects from making their way into your house.
If the window unit has a three-prong plug, make sure to connect it to a grounded receptacle. If you must use a two prong adapter, make sure you properly connect the adapter’s grounding tap to the outlet. If you’re unsure about electricity, don’t take a chance – call in a professional electrician. Window air conditioners consume a lot of power so it’s important that they’re wired properly.
Finally, once you have your window air conditioner unit installed, the window locks will no longer work. For security, cut a stick to fit between the top of the sash and the upper window frame. This may prevent a burglar from prying open your window.
Add a whole house fan
Probably one of the most effective and efficient, low cost, systems for cooling your house is the “whole house fan“. Not to be confused with smaller attic fans, these large fans are mounted in the ceiling of the uppermost floor of your home.
They work by drawing air from open windows in the house into the attic, where it is released through enlarged vents to the exterior. The air flow in the house can be controlled by the number and location of open windows, as well as the speed of the fan, which usually has several settings.
Also, by using a time switch, you can set the whole house fan to run for an hour or so while you’re falling asleep, then automatically switch off at night. The whole house fan then automatically switches off and won’t run all night when the temperature drops.
Upgrade attic insulation
Keep that precious cool air indoors by adding insulation throughout your home. Some of the leakiest, most under-insulated homes are located in southern climes where winters tend to be mild, so bulking up insulation before high heat arrives is an absolute must.
While most people think about installing attic insulation in the fall, insulation works equally well in the summer to keep hot attic air temperatures from penetrating the attic ceiling. Well insulated homes should have a minimum of 8 inches of ceiling insulation.
Insulation is easy to install with just a few precautions. Make sure to cover exposed skin, especially when using fiberglass insulation. Also, be sure to wear a dust mask to prevent breathing in fiberglass particles and wear safety glasses to protect your eyes. If doing the attic insulation job in the summer, start early in the morning and quit well before the sun heats the attic to uncomfortable temperatures.
Improve attic ventilation
Drafty attics, not drafty houses, make for very efficient heating and cooling. In fact, a well ventilated attic should be as close to the ambient outside air temperature as possible. To achieve this, most homes should have a combination of ridge and soffit vents. The ridge vent, mounted along the entire peak of the roof, will allow trapped warm air and moisture in the attic to escape to the outside.
To make this happen however, lower vents must be added at the “soffit”, which is at the underside of the roof overhang. With these vents installed, air is pushed into the soffits, rides up the underside of the roof sheathing, and exits the home at the ridge.
The nice thing about an attic ventilation system is that it works year round. Unlike attic fans which run only in the summer and cost money to operate, ridge and soffit vents work together to take out hot air in the summer, cooling your home, while taking out trapped moisture in the winter which can cause insulation to become damp and inefficient.
Use attic fans wisely
Attic fans, mounted on the roof, are important when cooling your home by reducing the temperature of trapped warm air in the attic. If the attic is cooler, the house temperature will be lower and air conditioners will not have to work nearly as hard to keep the home at a comfortable temperature.
Attic fans are inexpensive and run by a thermostat which turns the attic fan on automatically whenever the attic temperature gets hot. However, attic fans are not advised for homes with central air conditioning. The reason? They tend to pull so much air out of the attic it becomes depressurized and pulls air from the house potentially driving up cooling costs.
6 free ways to lower home cooling cost
Here are several other ways to improve your home’s air conditioning efficiency that you can do around your house.
Position room fans
Ever wonder just why you feel cooler when you stand in front of a fan, even though the air doesn’t actually get cooler? The reason is something called “evaporate cooling”. Basically, the moving air causes moisture on your skin to evaporate.
As it does, the evaporation process cools your skin so you feel more comfortable. To take advantage of this effect, position room fans for maximum air circulation. If you’re using a window fan, open another window across the room to provide good cross ventilation.
Keep storm windows closed
The same air that leaks in during cold weather leaks in during summer and drives up cooling costs, so keep storm windows closed in rooms with window air conditioning units for extra cooling comfort and efficiency. One hint: make sure the bottom of the storm window has “weep” holes. These small holes let water out of the inside of the storm window so trapped moisture won’t rot your wooden window.
Pull the shades
Keep rooms cool by closing shades and blinds during sun-filled hours of the day.
Spin out coolness
Paddle fans are another popular version of the room fan and can help keep your home cool. While attractive, these ceiling fans are costly to run and an inefficient way to cool your home. One advantage paddle fans do have over other types is a reversible motor.
By controlling the direction of the blades, you can use the fan to “pull” colder air up in the summer and “push” warm air down in the winter. Fans installed at the peak of cathedral ceilings can be very effective in winter by helping to re-circulate warm air that would otherwise be wasted.
If you have ceiling fans in your home, get them spinning in the right direction for cooling efficiency by setting their reversible motors for counterclockwise motion that pulls cold air up.
Landscape for shade
Strategically planted shade trees not only ad interest to your landscaping but also keep your home cool during the summer months, trimming your air conditioning expenses by as much as 25 percent.
Work at night
Keep your home cooling efforts efficient by limiting use of heat-generating appliances like clothes dryers and dishwashers to evening hours. Improving your home’s air conditioning and cooling system efficiency can be achieved through a combination of common sense maintenance tips as well as by reducing the heat that gets into your home. Follow these steps and you’ll improve your air conditioning efficiency, reduce cooling costs and improve your comfort all year long.
Test your home
Making energy efficient improvements can help shrink energy bills year round. Home Performance with ENERGY STAR, a national program from the U.S. EPA and U.S. DOE, offers a comprehensive, whole-house approach to improving energy efficiency and comfort at home, while helping to protect the environment. With Home Performance with ENERGY STAR, any size or style home can be improved to reduce energy costs up to 30 percent.
A Home Performance with ENERGY STAR contractor will perform a comprehensive home assessment to test the performance of any home with respect to energy efficiency, comfort, health and safety. The contractor will identify opportunities for improving a home’s efficiency and provide the estimated cost of making the improvements. The program even offers low-interest financing to help pay for the recommended work.
By following these tips, you can run your air conditioner more efficiently, thus lowering costs while remaining cool and comfortable in your own home.