Are you noticing your AC is not working? It’s getting hotter in your house instead of cooler? There are several components to your HVAC system and all it takes is one small issue to keep the whole thing from operating as it was designed. Before you panic, here are eight common reasons your AC is not working:

  1. The Batteries in Your Thermostat are Dead
    Your thermostat isn’t showing anything on it’s display? No sweat! This is a simple DIY fix. More common than you would think, the batteries just need replacing. Keep extra batteries around the house for such unexpected occasions. Even better, be proactive and change your thermostat batteries on a yearly basis.

  2. The Thermostat is Not Set to “Cool”
    Also, more common than you think. You have a lot of things on your mind and this one is easily overlooked. In order for the thermostat to tell your system it wants to turn on the AC you have to switch it into cooling mode. Before calling a local professional, take a look to make sure you have done this. 

  3. The Indoor or Outdoor Disconnect Switch is Off
    Each of your appliances, indoors and outdoors, is required to have a disconnect switch located next to it. It’s possible this was turned off accidentally. Give it a quick check before contacting a local professional.

  4. The Circuit Breaker Tripped
    Your electrical panel is usually located in your basement. If the box is appropriately labeled, check the breaker for the AC to see if it is in the off position. Breakers are designed to trip when a circuit gets overloaded. Reset the breaker and try turning the AC on again. If the breaker trips again, leave it off and contact a local professional.

  5. Blown Fuse or Blown Transformer or a Short in Electrical Wiring
    Each of these issues will stop your system from working but are a little above DIY status. Unless you’ve got special training and the right tools, you should contact a licensed HVAC professional.

  6. Capacitor Failure
    Your system might have two separate capacitors (start and run) or a dual round capacitor that accomplishes both, but either way, if these components were to fail, you can expect to have a problem with your AC equipment. Either your motor will fail to start or it will run with extra torque, overheat and reduce its life expectancy. This is another issue that calls for a local professional.

  7. Dirty Coil
    When your thermostat is on cool but the air coming out is coming out at room temp, you might just have a dirty coil. There are two AC coils, one in your outdoor unit and one in your indoor unit. They can get dirty if you don’t have your HVAC system serviced on a regular basis.

  8. Frozen Coil
    A frozen coil will block airflow through your HVAC system. Take a look at the refrigerant lines connected to the inside or outside equipment. If you can see a huge block of ice this may have occurred by one of the following issues:
    • Dirty Air Filter.
    • Refrigerant leaks.
    • Improper refrigerant charged.
    • Closing half or more of your supply vents.
    • Obstructed return or supply vents.

A dirty air filter is the most common offender, but a range of issues could cause this problem. Turn off your system allowing for it to thaw while you wait for a local HVAC professional to investigate why your AC is not working.

Most of these problems are preventable or easily rectified when you have the right team on your side. Levco recommends having your system inspected by a local professional every spring to identify problems before the heat of summer. Find out why Levco recommends you have an AC Spring Check.

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