Why is My Air Conditioner Running But Not Cooling?

Why is my air conditioning not cooling?

An Air Conditioner not cooling your home is a big problem.

After all, that’s its one job.

When your AC doesn’t perform as it should, it’s frustrating, time-consuming, and very hot.

There are several reasons your Scarborough air conditioning may not be adequately cooling your indoor air. We’re going to walk through each one – and how best to fix your air conditioner so it can get back to blowing cold air.

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1. Your Thermostat Isn’t Cooperating

Is your air conditioner not cooling? The first stop is your thermostat settings.

You should make sure that your thermostat is not only set to ‘ON’ but that it is set to ‘COOL’. Test that it’s working by setting the thermostat several degrees cooler than the stated temperature. You want to feel that chill! If this fixes it, program your desired temperature setting.

If you can hear the air conditioner running, but minutes later still don’t feel any cool air coming through the vents, there could be something wrong with your thermostat and its electrical wiring. Fixing that problem is best left to a professional.

Dr. HVAC’s Note: You should also make sure all your windows and doors are sealed shut, and your supply and return vents are open and unblocked. It’s little things like this that are easy to forget about but super easy to fix.

2. A Breaker Has Been Tripped

Dr. HVAC’s Note: This tip is only for those homeowners whose air conditioners are not running at all.

Your AC runs on electricity. No electricity going to your air conditioner means no cool air making your home a summer paradise.

It’s time to travel to the location of your breaker panel, and do a check. The breakers for your air conditioner should be clearly labelled. Flip them off and on again, and see if this makes a difference.

3. You Have a Clogged Air Filter

Next stop: the air filter.

Just because your air filter is located in your furnace’s blower doesn’t mean it isn’t used by your air conditioner. Your furnace’s air handler is what pushes the cooled air through the filter, through your ductwork, and into your home.

Therefore, if your air filter becomes clogged with dirt and debris, it’ll act a lot like a cork in a bottle: little to nothing is getting past it.

We recommend checking your filter once a month, and changing it at least every 3 months – more often if you have hairy pets, allergies, or a lot of people living in your home. You may also have a reusable filter that requires cleaning at the same intervals.

Air filters can be found at local hardware and home stores.. Make sure you replace your current dirty filter with one that is the same size.

4.Your Outdoor Unit is Coated in Dirt and Debris

Sensing a theme here? Dirt is no friend to a central air conditioner.

Your air conditioner condenser is located outside your home, and left exposed to the elements when in use. After a while, all that wind and rain is bound to blow some dirt and debris into it.

If there’s too much dirt, your condenser can’t perform the heat exchange process efficiently.

There are things you can do to help with this particular problem. For example, tidying up the landscaping around your condenser will help keep branches, bushes, and other vegetation from adding to the debris buildup. We recommend keeping about 46 centimetres of space clear on all sides of your condenser.

You should also wash your condenser regularly with water and soap. Gently wipe away dirt from the condenser fins, being very careful that they don’t break.

In the off-season, make sure your condenser has a cover and it is secured tightly. To defend yourself against dirt and debris, you may want to consider an air filtration system to keep your air quality clean.

5. Houston, We Have a Mechanical Problem

While annual maintenance is an excellent way to reduce your risk of mechanical breakdowns, they can still happen.

Whether it’s a broken AC fan motor or compressor, a mechanical problem could be the reason your AC is not cooling properly.

If you suspect a mechanical problem, you should call us right away.

6. The Refrigerant in Your Air Conditioner is Leaking

Air conditioners use continuously circulating refrigerants to cool air. Normally the level of refrigerant never changes and your air conditioner is perfectly fine.

If you spring a leak, that refrigerant level drops – and so does the amount of cool air you get.

Refrigerant leaks can be identified by ice buildup, hissing noises, or a noticeable decrease in cooling efficiency.

If you think you have a refrigerant leak, turn off your air conditioner and call us right away. This is a problem that should only be handled by experienced professionals.

7. Air Conditioning Wasn’t Properly Installed

Unfortunately, we see this all the time with both air conditioners and furnaces.

An improperly installed air conditioner just won’t provide the cool air you need in an efficient manner. Your Central air conditioning system has more pieces that could have been installed incorrectly than a standard window ac unit.

This is something you’ll notice after you get a new air conditioner. We can provide you with a second opinion, and do what we can to fix any potential problems.

Dr. HVAC’s Note: The size of your air conditioner is also incredibly important. If it’s too big or too small, you won’t be able to efficiently cool your home. Before you buy an air conditioner, meet with a qualified home specialist who can perform an evaluation and make recommendations.

8. Your Ductwork is Leaking

Any cracks or spaces in your ductwork will let cool air seep out and away. It’ll never reach you, and you’ll think your AC is not cooling your home.

In fact, it is – just not where and the way you want. The cold air blowing out is not getting to you, leaving your air conditioner running longer than needed. That’s a waste of your money and is incredibly frustrating.

We can perform a ductwork inspection, diagnose the problem, and provide recommendations for next steps.

9. Your Air Conditioner is Over the Hill

There comes a day when even the best air conditioner in the world just gets to be too old.

Generally, after 15 years, you want to start paying close attention to how your air conditioner performs. If it gets to a point where you’re spending hundreds of dollars a year to keep it going, or your AC is not properly cooling your home at all, it’s time for a replacement.

The experts at Dr. HVAC can perform an in-home consultation and walk you through the latest models, making recommendations for your home and your needs. We understand that a new AC unit replacement can be hard on the budget. Not to worry, Dr HVAC offers financing options on our HVAC systems.

10.Your AC System is Freezing Up

If you checked your system’s air filter and found a dirty air filter waiting for you, it’s possible that the lack of airflow caused your refrigerant to over-cool and freeze any condensation and leave you with a frozen evaporator coil. Dirt may also be causing a blockage in the drainage pipe, or a refrigerant leak in the refrigerant line causing the evaporator coil to freeze over.

If your refrigerant lines are intact, it may be due to an issue with the fan- meaning condensation will build up on the evaporator coil and disturb the cooling process.

Dirty air filter, refrigerant leak, or whatever the issue may be, a frozen Air Conditioning unit is a problem that needs an HVAC professional to fix.

Get Help from the Professionals at Dr. HVAC

When your outdoor unit is not cooling your home, the best thing to do is call in the experts. We’ll respond quickly, arrive on time, and get your cool air back as soon as possible. No matter if you need to repair your Lennox AC unit or Carrier AC repair.

After we get the cool air back, we can keep it that way with annual AC maintenance. A tune-up each year will not only minimize the risk of breakdowns but will increase the lifespan of your AC and save you money on your energy bills.

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