Do you ever wonder how cold your air conditioner should blow? When you turn on the air, you expect it to be ice cold, right? But sometimes, it just doesn’t feel as cool as it should be.
Well, it’s not just an annoyance when your air conditioner blows warmer than it should be. It’s also a waste of time and energy. Just like a car that gets bad gas mileage, an air conditioner that’s not cooling as much as it should means money out of your pocket.
So, how cool should the air coming out of the vents be? As a general rule of thumb for home air conditioners, the air should be about 15-20 degrees cooler than the air taken in.
In other words, if the air temperature in your house is 78 degrees, then you would expect the air coming out of the vents to be between 58 and 63 degrees. It doesn’t have to be exactly in this range, but it should be close. If the cooling differential is less than 10-12 degrees, it could indicate a problem.
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How to Check the Air Temperature Accurately
If you want to make sure your air conditioner is blowing cold enough, checking the temperature is simple. All you need is an infrared thermometer, which you can easily find for about $20 on Amazon.
To get an accurate reading, first, measure the temperature at the air intake. This is where the air is pulled into your air conditioning system to be cooled. Avoid taking the temperature at the thermostat or elsewhere in the house because the readings may vary and give an inaccurate assessment of how much the air is actually being cooled.
Next, measure the temperature of the air coming out of the vents. Simply point your thermometer into the vents to take the reading. Keep in mind that if you have central air conditioning with ducts running through the attic, you might notice a temperature variance between vents close to the indoor air conditioning unit (sometimes located in a closet or attic) and those farther away.
As the cooled air travels through the ducts, the attic air will warm it. Therefore, you might see several degrees lower temperatures in vents closer to the unit compared to vents located across the house.
For the most accurate temperature differential, measure the vents closest to the air intake. This air has the shortest distance to travel, minimizing the impact of temperature differences.
Remember, you should be seeing a reading of 15-20 degrees cooler between the intake air and the conditioned air coming out of the closest vents.
What If You Have Big Differences in the Vent Temperatures?
If you find major differences in the air coming out of the vents (differences of 5-10 degrees or more) during your readings, there could be various issues. Most likely, it has to do with the ducting that carries the air from the air conditioner to the vents. Often, the insulation on the ducts can be ripped, torn, or too thin, allowing the heat from the attic to warm the air inside.
What If My Air Conditioner Isn’t Cooling Enough?
If your tests reveal that you aren’t meeting the 15-20 degree differential, it’s best to have a professional check your system. There could be a range of potential issues, from low refrigerant to insufficient insulation or dirty coils that cause inefficient cooling. The good news is that experienced HVAC (heating, ventilation, air conditioning) technicians can quickly pinpoint the problem and get your system back to blowing cold air.
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