Your AC will work harder to cool your home when outdoor temperatures are higher than normal. The compressor will run more frequently to reach and maintain the desired indoor temperature. The air conditioner may run all the time if the temperature hits 100℉ and soars even higher.
During heat waves, experts, including utility companies, recommend keeping your thermostat no more than 20 degrees cooler than the outdoor temperature. For instance, if it's 100 degrees outside, aim to set your thermostat to at least 80 degrees.
If you have noticed that your air conditioner has been turning on and off as frequently as every 10 minutes, your system is most likely in need of repair due to “short-cycling.” Short-cycling is when a system turns on and off abruptly and often.
Ideally, air conditioning systems should cycle for 15 to 20 minutes. Instead of frequently turning on or running continuously, the air conditioner will turn on two or three times an hour. A high temperature inside or outside your house will increase cycling times.
Once the AC completes a cycle of about 15 and 20 minutes, it should remain off for 7 to 10 minutes. This helps it cool off before starting another cycle. The stops happen 2 to three times per hour.
A common reason for a short cycling AC system is electrical problems. This may be caused by a bad connection, a broken thermostat, a faulty circuit board, a condenser or compressor not receiving power properly. To properly diagnose and repair the electrical issue, call a licensed HVAC contractor.
As long as you are staying comfortable, your home is reaching set thermostat temperature on very hot days and airflow from vents is normal, and your energy bills are about the same as they were last year – there's likely not a problem.
In Southern California, 100+ degree days are becoming more common. Extreme temperatures can put quite a strain on your AC. In general, air conditioners run in cycles of about 15 to 20 minutes.
Typically, short cycling can come from an incorrect unit size or programmable thermostat problems. However, it could also be caused by neglected routine maintenance or something that might require a simple repair.
Ideally, your AC should cycle two to three times per hour during normal weather conditions. However, various factors such as thermostat settings, outdoor temperature, system size, and home insulation can influence cycling frequency. If you notice irregular cycling patterns, it may be time for a professional inspection.
The system will turn off prematurely and then quickly turn back on in an attempt to reach the set temperature. The thermostat will incorrectly tell the unit that the set temperature was reached or vice versa. A miscalibrated thermostat puts lots of strain on the HVAC system and can be a difficult problem to notice.
Allowing your air conditioner to rest is an excellent way to extend its life and ensure it operates efficiently throughout the years. Air conditioners, like homeowners, require rest in order to recover and perform optimally.
Air Conditioners Have Limits
It's true that air conditioners do have limits when the outside temperature is extreme. This means that your air conditioner may be able to keep your home at 77 or 78 degrees when it is 104 degrees outside. But it might not be able to cool it down to 70 degrees during the heat of the day.
What should my AC be set at if it's 90 degrees outside? If the outdoor temperature is 90 degrees, it's recommended to set your thermostat between 75-78 degrees.
Setting your air conditioning to 72°F is generally considered a comfortable indoor temperature for many people. It strikes a good balance between comfort and energy efficiency, making it a popular choice for residential settings.
Typical AC Cooling Cycles
An AC that works will typically perform two or three cycles an hour. On moderately hot days, your AC should typically only run for 10-15 minutes to cool your house thoroughly. This means it will often run for around 10 minutes before shutting off and then stay off for about 10 minutes.
A refrigerant leak can lead to reduced cooling capacity and cause your AC system to run continuously in an attempt to reach the desired temperature. If you suspect a refrigerant leak, it's crucial to have a professional HVAC technician inspect and repair the issue promptly to prevent further damage to your AC unit.
The utility recommends a setting of 78 degrees when you're home, even though it's a saunce outside, and 82 degrees when you're not home. “Summer heat is tough on air conditioning units,” FPL says,”but cooling your home doesn't have to break the bank. Keep your energy costs under control.”
Here's the thing: It's normal for your AC to run continuously during hot summer months. You see, on extremely hot days—we're talkin' high 90s to 100s—your system needs to keep up with the incoming heat. To do that, it will run longer in order to maintain a constant, desired temperature in your home.
Keep Your Cool
Close your window treatments during the day when the sun is out. Turn your ceiling fans in a counterclockwise direction. Doing so will create a literal wind-chill effect that should allow you to set your thermostat about 4 degrees higher than usual -- and you won't feel one bit warmer.
The constant running of your AC unit will reduce pressure in the evaporator, or cooling coil until it freezes over, according to Cool Today. This is why in some cases, this constant running can be dangerous. The freezing of the coil can cause liquid refrigerant to flood back into the unit's compressor and damage it.
The short answer is yes, it is cheaper to leave your air conditioner on all day. But this does not mean that you should leave it on full blast, keeping your home so cold that you need a sweater or jacket to be comfortable.
The average cost per kWh in the US is currently $0.11, according to the Energy Information Administration (EIA). This means an AC unit could cost you from $5.17 to $5.94 per day to run. Or about $155-$178 per month you're running it.