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Evergreen Home Heating and Energy's mission is to make Puget Sound area homes the most energy efficient, comfortable homes in the country. Through our decades of knowledge and expertise, along with innovative and cutting-edge technologies, we believe we are the HVAC company that will make this goal a reality.

7 Ways to Increase Your Home Air Conditioner's Effectiveness on the Hottest Days of the Year

June 24, 2021

Here in Seattle, we’re expecting an unprecedented late June heatwave this weekend and into next week, with weather possibly getting into the triple digits for multiple days. People that have homes with central cooling may find their AC systems have a tough time keeping up with these extreme temperatures. Because 100+ degree days have happened so few times in Seattle’s history, these temperatures are above what air conditioning systems are typically designed to handle in our area.  Your home will still be much cooler than the outdoor temperature but may not be as cool as you normally like it. If your home has AC, here are some tips to help your AC system perform as well as possible in the 
upcoming heatwave:

7 Ways to Increase Your Home Air Conditioner’s Effectiveness in the Upcoming Heat Wave

1.    Make sure your filter is clean. A dirty filter will heavily restrict airflow in your home’s cooling system, drastically reducing its effectiveness. Filters should be checked every couple of months to make sure they are clean and not restricted. If your system uses disposable filters, you should change them whenever they get dirty and restricted, at least every few months. If your system has reusable/washable filters, we recommend cleaning them often to ensure maximum air flow across the coil.

2.    Make sure your outdoor coil is clean. A dirty outdoor coil will reduce your air conditioner’s efficiency and effectiveness, lowering the amount of cooling it is able to provide. Look for any kind of debris on your outdoor unit’s coil, including leaves, dirt, and cottonwood, which is abundant in our area especially this time of year. If you see any debris on your outdoor unit, it can be cleaned by spraying it down with a low pressure nozzle on your garden hose. To protect your unit’s electrical components during cleaning, we recommend safely cutting power to the unit by pulling out the fuses in the electrical disconnect, a grey box typically located on your home next to the unit.

3.    Don’t cook indoors if you can help it. This is a great time to fire up the BBQ! If you can, avoid using the stove and oven on extremely hot days. Not only will the oven and stove add heat into your home, but your exhaust fan will also suck out a lot of your precious AC!

4.    Do laundry first thing in the morning. Your washer isn’t a problem, but your dryer will not only cause your home to heat up, but it will also exhaust AC out of your home. Either plan to do your laundry during the cooler hours of the morning or take advantage of the sun and dry your clothes outside!

5.    Turn down the temperature on your thermostat early. We recommend setting your thermostat to the lowest temperature you would like to maintain in your home early in the day when it’s still relatively cool outside. If you wait until it’s hot inside and outside your home, it may be difficult for your system to recover fast enough to keep your home comfortable during the day’s hottest hours. On the other hand, turning the temperature all the way down to its lowest setting could be a mistake, especially if your system is a “single stage” system. If you set your thermostat too low, your system won’t turn off until it reaches its set point, which could potentially damage your home and equipment. We recommend setting your thermostat no lower than 70 degrees and setting it early in the day.

6.    Cover your windows. Use shades, blinds, blankets, or whatever you have available to block the sun, especially in south and west-facing windows. This will reduce the thermal load in your home, helping your AC system do its job more effectively.

7.     Run your central fan constantly. If you have a central AC system, your home likely has a central fan that can be run constantly. We recommend running your fan on hot days which can help mix cooler air on lower floors with warmer air on upper floors, evening out temperatures in your home.

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