We’ve covered the perks of always running your HVAC fan. But there are disadvantages such as increased energy usage and wear. However, there are reasons to consider having your AC in fan mode instead of cooling mode when you’re sleeping. Running the AC fan only at night allows air to circulate without overworking the air conditioner.
Saving Electricity by Cycling Off the AC at Night
To realize how this makes sense, it helps to understand how an AC works. First, the unit sucks in hot air. Then refrigerant absorbs and carries the heat away, which is released outside by the condenser. The refrigerant cools and travels back to the evaporator, and a blower circulates cooled air into the room. This process works in a continuous cycle until the actual temperature and set temperature match, at which point the thermostat signals the system to cycle off.
There’s some truth that cycling your AC off at night (and running the fan only) can save electricity. But this isn’t always so. Whether it promotes efficiency depends on:
- Outdoor Air Temperature: If the outdoor air is relatively cool at night, you can open some windows and the AC fan will help circulate it. Only keep windows open if there aren’t any security or air quality concerns. And be sure to close the windows before sunrise, when heat may start to enter your home.
- Outdoor Humidity: Opening windows isn’t going to have any benefits if the outdoor air is too humid. This will cause your AC to work harder. That’s because it must absorb the extra humidity and remove that moisture. In the process, it will increase energy consumption and your utility bill will go up.
- Use of Other Cooling Devices: Running a whole-house fan, exhaust fan, or even a ceiling fan at night can keep cool air circulating. These use less energy than running your central AC at full blast. The comfort level, however, depends on how high the outside temperature is.Â
A whole-house fan pulls in air through windows and exhausts it via the roof, so is effective even on hot nights. For individual rooms, ceiling fans help circulate air and create a wind-chill effect, so it feels cooler than it is. Running them along with an AC fan at night can improve comfort.
Tips to Get the Most of Running an AC Fan Only at Night
You can have a steady flow of air and save energy. If you prefer to keep the AC only on fan mode at night, here are some ways to improve comfort and efficiency:
- Switch the AC to “Auto” mode while running your ceiling fans; you’ll still feel the circulating air.
- Install a whole-house dehumidifier that turns on automatically to remove excess humidity via your ductwork.
- Upgrade to a variable-speed air conditioning system that runs at different levels to adapt to your cooling needs.
Running the Fan vs. Risking HVAC Wear
The AC uses less energy in fan mode than when cooling. But running the fan all the time can increase the amount of maintenance your HVAC system might need. That’s because the filter can clog up sooner and mechanical wear and tear can accelerate. Running the blower fan constantly in summer can pull more warm air into your home. As a result, you may need to run your AC system more frequently.
But running the fan at night, when it’s cooler, can reduce the demand. Since the fan will run only during certain hours, wear and tear may be less of a concern. Fortunately, some newer systems can be programmed to turn on the AC fan at certain times, for certain hours, or for a certain time interval per hour. You don’t have to keep getting up to turn it on and off.
The bottom line is, you can benefit by running your AC fan only at night, depending on a variety of factors.
Contact Sky Heating & Air Conditioning
For HVAC repair, installation, and maintenance services, and advice on using your AC more efficiently, you can trust Sky Heating & Air Conditioning. Our trained technicians help customers in the Portland area get the most out of their heating and cooling systems. Budget-friendly special offers, maintenance plans, and financing options are available; we’re also open 24/7 to provide emergency services. To learn more, call 503-673-9083 today.
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