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Is Your Air Conditioner Not Turning on? Try These Tips

Is your air conditioner not turning on? Having your cooling system not work on a warm, summer day makes the inside of your home quite uncomfortable. In addition to this, the high humidity can also cause property damage to your home and potential health hazards you’re your family. This is why when your air conditioner is not coming on, you should diagnose and repair it as soon as you can.

The first thing you want to do if your air conditioner won’t turn on is check to see if you have properly turned on the air conditioning system. If you are having problems with a brand-new unit, make sure you read the owner’s manual, so you fully understand how to turn the unit on, and how all the features that come with it work. Some systems have options like the delay timer and an automatic shutoff. In addition to this, you’ll also want to check your home’s breaker box to ensure the power hasn’t been turned off.

Once you know that your air condition’s problem isn’t a lack of power, then you’ll want to remove the faceplate and dig in. However, it’s important to remember that air conditioning systems typically last homeowners 10 or more years. Some systems can even last up to 20 years. So, if your system is not turning on, and your system is more than 15 years old, you might want to consider simply replacing the whole unit and investing in a new one.

For most air conditions, the faceplate will snap on and off. For others, removing the faceplate may involve taking out screws. Once you have it removed, you can then start diagnosing your system and get back to enjoying a cool home.

Inspect your thermostat

If you have central air, head to your home’s thermostat and inspect it to make sure that it’s not broke, stuck on “HEAT” or turned to the “OFF” position. If you do find that your thermostat needs repair, a replacement at your local home improvement store is quite inexpensive and not too hard to fix.

The air filter

Check the air filter. This filter should be checked every 2 to 3 months and replaced at least one a year. The reason being is because when your filter gets dirty and clogged, ice will begin to build-up on the filter preventing cold air from being blown out. As a result, the low-pressure switch in your unit will trip and shut down and cause the air conditioner’s compressor to stop working.

Safety and interlock switches

Many air conditioning systems have several safety and interlock switches that will automatically shut the system down if they get triggered. One of these for an example is the overflow pan. If the pan begins to overflow, the system will automatically shut down. Open your system and check to see if this is the case. If not, there’s a couple others that you’ll also want to check. These include:

  • Blower door safety switch – A safety device that will shut the blower door if the blower door is open.
  • Reset button electric motor– If your air conditioning system happens to overload or overheat, it will turn off. In this situation, you will need to let your unit cool off before you restart it.

Blowout compressor

If your air conditioning’s compressor is not working, this can also prevent the unit from turning on. If your air conditioning unit had been making buzzing or clanking noises before it quit turning on, it’s a pretty good clue that the compressor is going bad. Another clue that your compressor might be bad or may have blown out is if there’s a bad odor. Typically, compressors that are going bad or have been blown out will give off a recognizable odor. In addition to this, you can also perform a resistance measurement test on your compressor by investing in some sort of electromagnetic device from your local home improvement store.

If you do find that your compressor is in fact bad or completely blown out, you should have a repair man to replace it unless you have experience with HVAC repairs. Like mentioned before, if your system 15 years or older, it might be wise to just invest in a new air conditioning system.

Clogged condensate drain

Overtime, the condensate line can become clogged by algae and other blockages. If this line becomes blocked, like previously stated, the overflow pan will overflow and trigger the drain float switch which will turn off the system. To get your system up and running, you’ll first have to remove the blockage in the condensate drain. You will need to invest in a wet/dry vacuum and hook it to your home’s condensate drain line located outside using an attachment tool. Run the wet/dry vacuum for an average of three minutes. This should clean the line.

Broken motor

One good reason your air condition may not start could be due to a faulty motor. Homeowners who have not properly taken care of their system will decrease the life of it. It’s recommended that at least once a year you clean and blow the dust and grime out of the motor. This will keep it running smooth. However, if you’re motor is faulty, you’ll have to decide whether to call a technician and have it repaired or simply invest in a whole new system.

Refrigerant deficiency

When your air conditioner won’t turn on, you should check to see if the refrigerant in your system has decreased to an extremely low level. A refrigerant deficiency can cause your system to not to on at all. However, unless you know what you’re doing and have experience, you should call a technician and have them replenish your refrigerant.

If after you have inspected and tested your system thoroughly, your air conditioner is still not turning on, then you’ll want to hire a professional company to come and diagnose the problem. However, like mentioned earlier, if your air conditioner won’t turn on, it may be time to replace the whole unit.

Michael Joseph