Why Is My Upstairs So Hot Even With The Air Conditioner On?

by | Dec 20, 2022 | AC Maintenance

Air conditioners are designed to bring comfort and safety to your home in the Texas summer heat.


Unfortunately, many people find that their upper floors get too hot in the summertimeeven when their AC is on full blast. In this article, we’ll tell you why your upper floors get too hotand what to do to fix the problem. 

Heat RisesSort Of

You’ve heard the expression “heat rises”, so you might not be surprised that your upper floors are hotter than your main floor or basement. 


Truth be told, though, it’s not heat that risesit’s hot air that does. Heat is energy that travels from hot to coldit can move in any direction.


Hot air, on the other hand, does rise. That’s because air expands when it’s hot, and that expansion reduces its density. This causes the hotter air to “float” on top of cooler airand it means your upper floors will get warmer than your main floor.


One way you can prevent this is with proper insulation. Insulation resists heat flow and can act as a barrier between the air on your upper floors and the air on your main floor. 

There May Be a Problem With Your Air Conditioner

Unless your insulation between floors is perfect, your upstairs will almost always be a little warmer than your main floor. That being said, if there’s a drastic difference between your upper and lower floors, it may be because there are problems with your AC system. Issues that can cause a difference in temperature between floors include:


  • Dents, cracks, holes, and other defects in your air vents
  • An air conditioner that’s too old
  • An air conditioner that’s undersized
  • Air filters that are clogged
  • Registers that are closed on the upper floors
  • And more


In most homes, air conditioners are found on the main floorand hot air rises. When combined, these two factors make it much more likely that hot upper floors are a symptom of problems with your air conditioner.  

How You Can Cool Down Your Upper Floors

There are a few tips and tricks you can use to keep your upper floors cool, even in the dog days of summer. You should:


  • Close blinds and shades to block the sun
  • Insulate between floorsand insulate your attic
  • Repair and maintain your air conditioner
  • Repair your ducts
  • Upgrade your AC system


There are a couple of ways that upgrading your system can improve circulation to your upper floors. The first is that a properly sized new system may provide more cooling than your old system. The second is that you can upgrade to zoned systems, which enable you to set the temperature for different zones individually. This gives you better control over the amount of cooling your upper floors will receive. 



About The Author

John Magninat

John Magninat

Owner John Magninat is a third generation air conditioning repair man. Classic Services Air Conditioning & Heating is a family company with family values and our customers are our top priority.

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