Air conditioning is a common topic of debate in many households during the summer. Whether it's finding the right temperature for maximum comfort or saving money on electricity bills, people have pretty clear opinions on the "right" way to use their air conditioner.
Some common settings on a typical central air conditioner can also be confusing, such as the difference between the "On" setting and the " Auto " setting . So we consulted with an expert to clarify the issue and confirm the proper air conditioner settings for maximum efficiency.
What is the difference between the "Auto" and "On" settings on an air conditioner?
First of all, the 'Auto' and 'On' settings on a unit or thermostat refer specifically to the fan inside the unit. ' When the fan is set to 'on,' the fan will run continuously, ' explains Stewart Parnacott, Ph.D., owner of Varsity Zone HVAC and Director of Ready Wellness. ' Whether the AC is cooling or not, the system is drawing air through the vents in a continuous cycle. 'Auto' mode only runs the fan when the system is cooling, and the units will turn off when the thermostat reaches the set temperature. '
' Think of 'automatic' as a motion-sensor light that only turns on when needed ,' adds Gerrit Jan Reinders, HVAC expert and CEO of Reinders Corporation. '' On' is like having the lights on all day. '
So the difference between the two is that 'on' mode allows the fan to run continuously, while 'auto' mode only allows the fan to run occasionally — but further consideration is needed to determine which mode is best for your home. While there is one mode that experts agree is best for everyday use, there is a time and place for both 'auto' and 'on' modes, so it's important to understand the benefits & use cases of each.
When should I use "Auto" mode on my air conditioner?
Every air conditioning expert advises: "Auto" mode is the obvious choice for everyday use. The main reason for this is that "Auto" mode saves energy, and therefore, saves money .
'This mode is more energy efficient because your fan isn't running 24/7,' says Reinders. 'Keeping the fan on all the time can increase your monthly electric bill by $20 to $50. '
TJ Laury, president of Ben's ProServ, agrees, adding that " auto " mode balances comfort and efficiency. " Continuous use of the fan [while it's on] will significantly increase your energy bill and cause wear and tear on the fan motor and the entire system ," he says.
One potential downside to ' auto' mode, however, is that the air can get a little still between cooling cycles, since the fan won't be running. But Benjamin Uscilla, HVAC technician and owner of Evergreen Heating and Cooling, has an easy solution to this problem. ' Sometimes the best trick is just to turn on the ceiling fan and turn the thermostat up a few degrees. You'll still feel cool, and it'll save you money.'
When to use "On" mode for air conditioner
While all experts agree that 'auto' is best for everyday use, they also agree that there are times when 'on' is a better choice. In fact, Danny Pen, an HVAC expert and president of New Era Plumbing & HVAC, sums it up quite well: ''Auto' for everyday use, and 'on' for special occasions. '
So what are those special occasions?
One situation where you might want to use the 'on' setting is if your home has different hot and cold spots. If your bedroom is always warmer than your living room, having the fan on all the time will help mix the air and even out that temperature difference. The constant airflow can help create more balance between rooms that never seem to maintain the right temperature.
The ' on ' mode can also be a good preventative measure for indoor humidity. This is a good option if you need to reduce humidity buildup in a basement or stuffy area outside of a cooling cycle. However, this is not a reliable solution in all cases. If you live in a humid climate, the ' on ' mode can actually make the house a bit stuffy, since the fan itself cannot pull moisture out of the air.
The final thing to consider when choosing the ' On ' mode in some cases is if you or someone in your family has allergies or asthma, as the air will be constantly moving through the filter. If you live in an area with a lot of dust, lots of allergens, or where wildfires are common, running the 'On' mode with a high-efficiency filter during certain hours, such as at night, can improve indoor air quality when combined with a well-maintained, airtight duct system.