11 Of The Most Common Central Air Conditioner Problems In 2023

Common Air Conditioning Problems

Air conditioning = summertime bliss… as long as it is working right, that is. But every once in a while, air conditioner problems inevitably pop up. Be prepared for Lennox AC repair or Carrier AC repair. Read about 11 of the most common central air conditioner problems in 2023, plus step-by-step solutions.

1. Air Conditioner Running All The Time

In the middle of hot, sticky GTA summer, you use your air conditioner a lot, but should the AC really be running all the time? Usually, central air conditioning cycles on and off several times an hour to reach and maintain your thermostat temperature setting. However, if the central air’s going non-stop, you could have a problem.

SOLUTION: The first step is to change your air filter. (It’s always a smart idea to try this right away; filters ought to be changed every 30-90 days for peak air conditioner performance.)

If that doesn’t help, talk to an HVAC expert. Maybe your system just requires cleaning or a refrigerant leak repair. However, when the issue is caused by an air conditioner that’s ageing out or was too small to begin with, you’ll probably need an AC replacement. The good news: due to recent advances in air conditioning technology, the AC you buy today will be much more energy-efficient than a few years ago.

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2. Refrigerant Air Conditioner Leak

Your older air conditioner probably cools with Freon. Unfortunately, this refrigerant, once in widespread use, is now being phased out by Canada’s government. As a result, only recycled Freon is available in 2021, and even this is becoming more expensive and harder to obtain.

Since your central air conditioner is a closed system, the Freon inside won’t evaporate or get used up. Theoretically, it could last forever… unless the system develops a leak, which will cause your air conditioner to work overtime, trying to compensate for the missing refrigerant.

SOLUTION: Contact an air conditioning repair professional.

3. Air Conditioner Water Leak

Occasionally, you might spot a puddle of water under your AC’s outdoor condenser unit. This could be completely normal if water leaks only while the air conditioning is functioning, especially on extra hot, muggy days. An ongoing leak or a large amount of water, on the other hand, indicates a problem.

SOLUTION: Change your filter if it is clogged or moist. On milder days, check the outdoor temperature; operating air conditioning in weather below 16 degrees C may result in frozen coils and leaking water. If the problem persists, call for a professional tune-up.

4. Air Conditioner Making Loud Noises

As a rule, central air conditioners tend to make a certain amount of noise. On startup, you’re likely to hear brief clicks, clunks, squeals, or shudders. During operation, a constant soft hum — plus the occasional gurgle — is par for the course.

However, beware of loud noises (like screechings or grindings), or new ones that develop suddenly. They could signal serious AC problems.

SOLUTION: Blocked airflow produces some dramatic sound effects, so change your filter before anything else. If you’re still troubled by unusual air conditioner noises, try to pinpoint the location and the type of sound, so you can describe them when you call an HVAC service for repair.

5. Air Conditioner Smells Really Bad

Smells from your central air can be really confusing for the simple reason that sometimes they’re not actually coming from the AC itself. Instead, odours somewhere in your home are being circulated via the HVAC ductwork. A couple of examples are the “rotten egg” scent of a natural gas leak or an odour of cigarettes due to someone smoking indoors.

An air conditioner malfunction indeed causes other aromas, for instance, burning, coolant, or exhaust.

SOLUTION: A cigarette odour is easily resolved by simply smoking outside. Most other air conditioner smells, though, signal an urgent problem. Shut off the system and get emergency HVAC repair.

6. Air Conditioner Not Cooling

It’s pretty frustrating when your central air is definitely running (you can hear the motor), but not giving you that nice cool relief from the heat. Reasons behind this span the whole range from “Whoops!” to more complex.

SOLUTION: Go through possible causes methodically, one by one. First, ensure you set the thermostat to COOL, not just to ON. Next, check that all your home’s windows and doors are closed, and your vents are open but not blocked by furniture or curtains. After that, replace the filter if it’s full of grime. Finally, clear debris off your outside condenser unit, and wash the fins gently, if necessary.

By this point, you’ve tried all the available DIY remedies. Is the AC still not cooling? It may have a refrigerant leak that needs attention, or it might require mechanical repair. Other possible solutions are professional ductwork inspection (the ducts may be leaking cooled air) or — worst case scenario — air conditioner replacement.

7. Air Conditioner Blowing Warm Air

An air conditioner blowing warm air is annoying and uncomfortable. Right now, the last thing you want is warm breezes wafting through your rooms!

SOLUTION: As above, ensure that your thermostat has not been adjusted to ON, or even HEAT. It has to be set on COOL. Change the filter to allow an adequate flow of air. Next, take a look at the circuit breaker for your condenser; if it has tripped, your air handler will continue working, but it will blow warm air until you reset the breaker.

No luck? Get an HVAC expert in to clean the system and take care of any refrigerant leakage.

8. Air Conditioner Freezing Up

You want your central air conditioning to be nice and cool in summertime — but not icy! An air conditioner freezing is frequently not such a big problem. Neglect it, though and it can eventually result in expensive damage to the AC system.

SOLUTION: You know the drill by now — change the air filter! In addition, raise the thermostat setting by a couple of degrees — particularly before you leave for work or go to bed at night.

If do-it-yourself methods don’t help, have an AC repair professional check for a malfunctioning AC fan, non-working drainage, or a refrigerant leak.

9. Air Conditioner Is The Wrong Size

Sorry to say, but your air conditioner could be the wrong size for your home. Why is this an issue? An undersized AC will never get your house quite cool enough, while an overly large system will lower the room temperature too fast, cycling so quickly that it dehumidify properly.

What’s behind this problem? Air conditioner salespeople who don’t know how — or don’t take the time — to calculate exactly what size your home needs.

SOLUTION: Buy your next central air conditioner from the team at Dr HVAC. We’re not in business to make quick sales no matter what — instead, we pride ourselves on our expertise and we’ll take the time to perform the detailed calculations necessary for a good fit.

10. Air Conditioner Keeps Tripping Circuit Breaker

Central air conditioners need a lot of power, and your electrical system has to be up to the job. If your AC keeps tripping the circuit breaker, it’s pulling a lot of amps — more than the breaker is rated for. Consequently, the breaker is tripping to protect your home from a fire hazard — electrical overcurrent.

SOLUTION: Do NOT simply ignore the issue and continue trying to reset the breaker. Start with your due diligence: change the filter and clean the outside condenser unit. However, for this problem, the source is probably a refrigerant leak or a failed component — motor, compressor, capacitor, or wiring. Repair by a qualified AC technician will be required.

11. Air Conditioner Isn’t Getting Regular Maintenance

An ounce of prevention is worth a pound of cure… and this old saying is certainly true of your air conditioner. True, regular AC maintenance costs a few dollars, but it saves you money in the long run. Look at the benefits maintaining your air conditioner will provide:

  • Improves energy efficiency, which reduces your electric bills and protects our environment
  • Lessens the chance of expensive and inconvenient breakdown
  • Improves home comfort and air quality
  • Keeps your warranty valid
  • Helps your AC to last longer, so you won’t have to replace it so quickly

With all those good things going for it, why not book air conditioner maintenance today?

Dr HVAC Will Solve Your Air Conditioner Problems

Got a problem with your central air conditioning? Call the DR! You can rely on Dr HVAC’s team of friendly experts for fast, accurate diagnosis and repair. We also offer HVAC maintenance and installation in the Greater Toronto Area.

Anna P was so satisfied with our AC repair that she wrote a rave review on Google:

“Sean came out to diagnose our air conditioner not working. Promptly discovered the problem and repaired right away. He is a very good technician. Very knowledgeable. Thanks to Dr Hvac for having someone like Sean on you team. Keep up the excellent service!”


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