Why Shouldn’t We Test AC Units in the Winter?

• By Andrew Fox
•

Did you know that 88% of US households use air conditioning to keep cool during summer?  With two-thirds of those homes depending on central AC systems, ensuring your AC unit is in peak condition is important for beating the heat.

You might be tempted to check on your air conditioner as winter approaches. You need to hold on! Testing your AC during cold weather may seem harmless, but it could lead to significant—and costly—repairs when summer rolls around. Just imagine the frustration of discovering your system is damaged right when you need it the most!

Many of our Naperville customers have been asking, “Why shouldn’t we test AC units in the winter?” This is a valid concern, especially with so many relying on their systems for comfort. 

In this blog, we will discuss the hazards of testing your AC unit in winter, what happens if you run your AC during this season, and when you should actually schedule your AC inspections. If you have questions or need assistance, contact your Chicagoland home inspection service, the BrickKicker—we’re always happy to help!

Why Test Your AC in Warm Weather?

When running your outdoor air conditioning unit, most manufacturers and HVAC experts will tell you one thing: it’s a big no-no to operate it in cold weather. You might wonder, why is that? Well, the answer lies in the oil that lubricates the compressor.

Think of it like the oil in your car—there are different types intended for different temperatures. Just as your vehicle needs the right oil to run smoothly in winter versus summer, your AC unit relies on the correct lubricant to function properly. The oil used in standard air conditioners is typically a heavier, summer-weight grade. This means it’s perfect for warmer weather but becomes too thick to circulate when the temperature drops.

So, if you’re wondering what is the lowest temp to run AC, keep in mind that running your unit when it’s cold can lead to serious operational issues. To ensure everything runs smoothly, it’s best to save your air conditioning tests for warmer months when temperatures are consistently above 65°F.

What Temperature is Too Cold for Air Conditioners?

For an AC test in winter, you may be thinking about what can be the lowest outside temp to run AC? Generally, most professionals advise against operating your central air conditioner unless the daytime temperatures are consistently above 65°F for at least 24 hours. This means that if you’re thinking about the perfect time for air conditioning testing, it’s best to hold off until warmer weather arrives. The ideal months for testing and using your air conditioner are typically from May through September.

Are There Any Exemptions?

The only exception to waiting for warmer weather to test your AC unit would be for those units with a crankcase or sump heater. These have a heating strip placed around the compressor and oil reservoir that help keep it warm and moving, but it’s still best to wait. There are even some more sophisticated units, with low-ambient temperature sensors that prevent cold weather operation.

What Happens If You Run Your AC in Winter?

As we mentioned earlier, when you run your AC in the winter, your oil can become far too thick as its molecules compress in the cold. This makes it difficult for the oil to circulate and your compressor to overheat. This could cause a perfectly good AC unit to fail, so the risk isn’t worth it. A much more energy-efficient way to cool down your home in the winter is to simply open the window and let some of the cold air into the house.

Additional Considerations for Air Conditioning Testing

It is important to recognize the impact and effects of low temperatures which are vital to the proper functioning of your AC unit. Many homeowners have questions and queries when it comes to testing their air conditioning systems during the winter. Let’s address some of these common concerns below:

  1. The minimum temperature to test AC should be above 65°F, as testing your AC unit in cold weather can affect its performance and longevity, making it important to schedule inspections during warmer months.
  2. What temperature to set air conditioner in winter? Ideally, set your AC thermostat to a higher temperature during winter, even if you aren’t actively using it to cool your house. Doing so can prevent damage to internal components by keeping them from working unnecessarily in cold conditions, which can strain parts like the compressor and lubricants, giving a longer lifespan to your system.
  3. When considering running AC in winters, it is important to understand the limitations of your system. Many homeowners question, whether is it safe to run the AC when temperatures drop? Ideally, it is not advisable to operate you unit below the recommended temperature, as doing so might lead to inefficient operation or potential breakdowns. 
  4. An aircondition test must be performed before the warmer months arrive. Regular air conditioner inspection is necessary to make sure your AC unit is in good working order so you are not caught off guard when the heat hits. It can also increase the lifespan of your AC unit. 
  5. Adding to that, it is also important to check air conditioner functionality routinely to confirm it’s ready for summer, prevent major issues, and also help you avoid any costly repairs. 
  6. You might also ask; can AC heat the room in winter? A standard AC unit is not designed to heat your home in cold weather. If you need heating, please consider using a dedicated heating system instead. 
  7. Finally, what is a compressor tester HVAC? And how does it help? It helps determine the condition of your unit. This tool is important for identifying any potential issues before they escalate, ensuring that your air conditioning system operates without hitch. 

By understanding these key considerations, you can ensure that your air conditioning unit is ready to perform effectively when summer arrives, all while avoiding the pitfalls of winter operation.

The BrickKicker is Always at Your Service

If you don’t know if you have a crankcase heater or you don’t know if your unit has a thinner grade of oil, it’s best to avoid testing your AC in winter. Please do not operate your central air conditioner until the temperature is over 65 degrees Fahrenheit for at least 24 hours. The risks are too high. Running a unit at that temperature could cause significant damage to a perfectly good operating unit. Now that you know what happens if you run your AC in winter and when you should test your AC unit don’t hesitate to contact us with any questions or schedule a home inspection. We are always ready to help! If you have other questions related to home care, be sure to explore our blog for dozens of other helpful reads about problems to look out for, DIY home care tips, and home inspection service intervals!