Before our Los Angeles summertime heat sets in, homeowners are gearing up for the next heatwave. You should plunge the thermostat down to minus 20 degrees, right?

And close off the vents everywhere but the living room? And buy a monster of an AC system?

Unfortunately, even though our home climate-control technology advances, the common misconceptions and misinformation around using them seem to stick around a bit longer than they should.

The team at JW Plumbing, Heating and Air set out to bust a few myths related to AC repair and use. Here are five common household air conditioning myths we busted that you should know before your next AC tune-up.

Myth: Larger System Means More Power

Would you put a V8 engine in a Camry? You could, but none of the other elements of the vehicle match the capability of a motor that size. Bigger isn’t always better.


Large, powerful systems blast cold air at a high volume. This can confuse your thermostat into shutting it down too early before the house is completely cool.

This is what’s called a “short cycle.” Over time, this will lead to increased wear and tear and more frequent AC repairs. In addition, the cooling power of a huge unit would also be canceled out by the energy it eats up, spiking your monthly utility bills.

A larger system won’t cool faster, and it won’t run efficiently. You need a system that is an appropriate match for the size of your home.

Myth: The Thermostat Can go Anywhere

This is a common design and installation mistake. A thermostat is designed to gauge the temperature around your home and heat or cool based on your settings.

If it gets confusing data, results will be inconsistent and energy-sapping.


Your thermostat should be installed in a spot where it’s not exposed to a lot of direct sunlight or increased airflow. These avoidable factors will disrupt the thermostat’s readings.

Palace your thermostat in an area of your home that’s the most temperature stable. Avoid the cool basement or the hot upstairs, if possible.

The thermostat also shouldn’t be placed on an exterior wall, where it’s closer to the outside elements. Your system may be compatible with additional sensors that can be spread throughout the home for more accurate overall readings.

Myth: We Only Use the Furnace During the Winter

Your air conditioner is not only cooling the air; it’s a climate-control device. It’s conditioning and dehumidifying as well as cooling.


Your furnace plays an important role in the climate control of your home. A whole-house system requires three elements to operate:

  • An air source
  • A method to distribute the air
  • A control system to regulate the temperature

Your furnace is still part of the cooling process, not just during the winter months. AC tune-ups are important throughout the year to keep the whole system operating efficiently.

Myth: Setting the Thermostat Lower Will Cool my Home Faster

Another myth busted! Reducing the overall room temperature of your home takes time.


If your home is nearly eighty degrees inside and you drop your thermostat to sub-zero, it will take roughly the same amount of time to cool down as if your home was ten degrees lower. The temperature setting does not affect the speed of the cool-down.

Most AC systems will cool the airflow when it reaches a predetermined temperature. Chances are, you don’t want to reach sub-zero temperatures. But if your thermostat is set lower than you need it, it will just keep running until the thermostat believes you’ve reached it.

If you’re aiming for sub-zero, that will never truly happen. You’re only costing yourself more money by trying to “outsmart” the thermostat.

Myth: Closing Vents in Select Rooms Will Save Money

Unfortunately, you’re not “saving” the cool air by doing this. But you will end up refrigerating the air ducts!


In reality, closing interior vents can throw off the whole system. Doing this creates uneven temperatures throughout your home. This also increases the pressure buildup in your HVAC system and may require AC repair.

The only way to effectively cool only parts of your home is if your system allows you to set up internal zones. This is more common in commercial properties, but some Los Angeles home AC systems have this capability.

How much time do you spend in your air ducts? We’re guessing none. Don’t cool them just for fun! Keep your vents open!
If you wait until your AC system is giving you problems, it may be too late to save. Yearly maintenance is highly recommended, especially in the hot Los Angeles heat.

Regular AC maintenance will also help you prevent the need for AC repair. Contact the JW Plumbing, Heating and Air team today and get your summer cool-down on the books!

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