How Long Should An Air Conditioner Sit Before Turning It On?

It’s not easy waiting to try out a new air conditioner after installation, especially on a hot day.

There’s nothing quite as annoying as not knowing how long to wait before turning on the air conditioner while sitting indoors on a sweltering day as sweat builds on your skin.

Here’s everything you need to know about how long to let an air conditioner settle.

How Long Should A New Portable AC Sit Before Turning It On?

If you’re moving a new portable air conditioner into your home, wait 24 hours before using it to be on the safe side. Many AC brands have variating wait times. They could take only half an hour or need a whole day to prepare and become operable.

While the air conditioner is settling, it should not be on its side or tilted. Doing so will extend the wait time and make you wait longer before using your AC.

So, how long should a portable air conditioner sit before turning it on? Reading the manual and following the manufacturer’s recommended wait time ensures that the appliance will work smoothly without bringing extra problems.

Portable AC Need To Sit Before Running

Why Is It Important For An AC To Settle First Before Running?

Turning on an AC before letting it settle can cause problems for the AC and the homeowner.

Within the air conditioner is a compressor that is responsible for providing cooling. It is one of the most necessary components of an air conditioner.

While an AC is settling, the compressor undergoes oil lubrication. The oil coats the compressor and small components so the air conditioner can function.

It is safer to follow the wait time and let the lubrication happen naturally. The AC won’t be problematic in the long run, meaning that homeowners will have less stress about maintenance and the air conditioner’s vitality.

What Happens If You Turn On Your AC Immediately After Installation?

Starting your AC right after installation is the quickest way to cause internal damage.

The air conditioner might not have had enough time to lubricate the compressor’s working parts like the solenoid valve or connecting rods are susceptible to damage.

An AC can work properly after installation, but experts would not recommend it. Over time, the damages will slowly appear as the AC continues to run until it eventually stops working.

Repairs will be necessary, and they won’t be cheap either.

How To Turn On Your Air Conditioner For The First Time?

Before you start your AC and wait for it to settle, there are some precautionary checks you can do in the meantime.

Inspect any wires connected to the AC to see no visible damage. Exposed wiring has a higher chance of causing an electrical fire while the AC is on.

Check the air filters to see if they are clear or need replacement. There’s always the chance for dust to build up while packaged, so a quick look inside before it starts will save you time.

The drain line by the indoor cooling coil needs to be unclogged and free of cluttered garbage. In addition, refrigerant lines should be insulated and checked for potential leaks.

Finally, clean out the vents of the AC to get the most out of the breezing air.

Once completing all these tasks, you can turn on your AC by following these simple steps:

  1. Set the wall thermostat to the desired level.
  2. Turn on the AC.
  3. Check the condenser fan outside to make sure it is running smoothly.
  4. Wait 10-15 minutes for cool air to enter the house.

How Long Should An AC Sit After Moving?

Air conditioners that are being transported or relocated have a chance to upset the oil distributions within. Other factors also determine the wait time after moving.

The type of air conditioner determines the wait time. You can usually turn on a portable air conditioner after 8-24 hours of settling, while a window AC works best after a whole day.

The age of the AC can affect how long to wait before turning on the air conditioner. Old ACs might require more time for the oil to settle and are prone to large movements and disturbances.

The bottom line, it depends on the machine and how it operates.

Does An Old AC Need To Settle If It Hasn’t Been Used For Several Months?

An AC that has remained in storage longer than a season needs time to settle.

There’s very little thought about an old AC once it has done its job. Some homeowners might just lay it on its side and allow it to collect dust until summer rolls around.

During that time, the AC loses lubrication on the compressor because the machine is sitting in the wrong position and fails to get enough oil.

When putting away an AC, make sure to keep it upright for the lubricant to remain in place. Doing so will avoid the hassle of buying a new AC.

Does Old Portable AC Need To Settle

People Also Ask (FAQ)

What temperature should I set my air conditioner for the first time I use it?

According to the U.S. Department of Energy, the recommended temperature for most ACs is 78 degrees Fahrenheit. Certain factors like the time of day or home insulation fluctuate the desired temperature, but it’s encouraged to keep the difference between outdoor and indoor temperatures as small as possible.

How long does it take for Freon to settle in an air conditioner?

Although Freon usually only takes a few minutes to settle in your air conditioner, the oil in your air conditioner needs time to settle. This aspect is especially true when your air conditioner has been on its side or back.

Can you turn an air conditioner sideways?

Leaving an air conditioner on its side will let the oil pool around the bottom half of the compressor, leading to compressor burnout. Prolonging this position can damage the compressor mounting and lead to a faulty machine.

Does tilting the air conditioner have the same effect as allowing it to settle?

Any amount of tilting does not allow the AC to settle. Some air conditioners are slightly tilted to dispel condensate water from the machine. Too much tilting can damage the compressor and diminish the necessary oil for lubrication.

How long can you run the air conditioner after settling?

After allowing the AC to settle, it will be able to keep running for long periods. Be mindful of routine maintenance and usage, as the energy bills can be expensive.

Will allowing an AC to settle make it cool your home faster?

Letting an AC settle delivers a better chance of keeping cool air running smoothly during hot days. You will have no other problems and don’t need to wait longer than needed.


To get the most out of your air conditioner, read your manual and see the approximate wait time for settling. Always leave the machine upright and avoid movement while the oil lubricates the compressor. Follow these steps to keep your air conditioner effective and to get your cool air pronto.

Josh Mitchell

Josh Mitchell

My name is Josh and I am obsessed with DIY and improving my family home. HVAC topics can be tricky for homeowners so I decided to share my knowledge on the subject. When I am not working on DIY projects, you can find me at the beach or my local coffee shop.