AC unit not blowing cold air? This is every homeowner’s nightmare. Your AC running but not cooling your house calls for you to contact your HVAC company for AC repair.

AC not cooling your house is the situation you do not want to get stuck in, especially when the temperatures are skyrocketing.

call 661-888-0248

Contact us 24/7 today to make an appointment.

If your HVAC system is already not blowing cold air, you are already in a sticky and an uncomfortable situation. We will, therefore, not waste your time; we will get straight to possible reasons behind this.

And even more importantly, we will accompany all this with solutions to get your HVAC system back on track.

Let’s go.

Why Your AC Unit is not blowing Cold Air?

When your air conditioning system is not blowing cold air, you first want to know why.

Of course, there is an issue that needs to be solved. You may need to call for an HVAC professional with many of these issues. However, there are some simple problems that you can solve yourself, and your AC will be back on its correct path.

Here are the reasons your air conditioning system is not blowing warm air and how to react in all the situations.

Thermostat Settings not Correct

Is your central air conditioning system on but not cooling the house? If so, the first question you should ask yourself is:

Is my thermostat set correctly?”

If you have set your thermostat on a higher side, it may not be turning on when you switch it on. For instance, your thermostat may not turn on at 24°C while your air conditioner temperature setting is at 28°C.

Also, you need to check if it is on the “on” setting instead of “auto”

Other things to verify to ensure your thermostat settings are correct:

  • Is your air conditioner’s shut-off switch flipped?
  • Are your breakers in the right shape? Ensure nothing is tripped.

If you find out that your thermostat setting is the problem, you need to reset it. This is a simple DIY you can do in minutes. Program the thermostat’s temperature a few degrees lower than the house so that you can test your air conditioning unit.

For example, if your house is at 25°C, you can have your thermostat at 20°C. This allows you to notice the difference.

It will take several minutes for you to feel the cold air. It will not happen right away.

After a few minutes, place your fingers on the air vents. You should feel cold air coming from the vent after around 5 minutes.

Chances are high; you need to set your thermostat well. However, if you do not feel any cold air from the vents, there may be an internal problem. And this means you may need to call for professional AC repair.

Remember: An old thermostat or low battery on the thermostat could also be the issue. Also a wrongly set thermostat could be the reason for AC unit running when turned off

Dirty Air Filter

Dirty air filters are another possible reason for air conditioners running without cooling your house.

And, this is another problem you can quickly solve. Typically, you can prevent this with regular and proper AC maintenance. However, you can still DIY replace your air filters if it is already an issue.

A central air conditioning unit with dirty and clogged filters limit airflow into your home. This deteriorates the air quality. Also, staying long with clogged filters, you risk damaging other parts of your HVAC system, such as the evaporator coil.

If your HVAC air filters are dirty or clogged, you will notice that the system is not cooling the house. Besides, you will notice that the air is more stuffy and the surfaces are dusty.

We recommend that you change your air filters monthly.

Dirty Condenser

Another reason there is no cold air blowing from your air conditioner is a dirty condenser unit.

The condenser is the outdoor unit of your air conditioner. When dirt or debris clogs the condenser unit, it will interfere with the process.

With dirt and debris, your air conditioner will have to work extra hard to pull in air and cool it.

Cleaning the condenser unit is a simple yet delicate process. AS you do it, you need to be careful to not bend or break anything. Use water and a mild detergent to gently wipe away the dirt. Please clean it up using a hose with gentle pressure.

However, you may want to minimize dirt accumulation in your condenser in the future. It is outside, therefore, exposed to a lot of dirt. First, have a weatherproof cover on your system whenever it is not used. Also, ensure that the area around the condenser unit is weeded and free from shrubs.

Possible Refrigerant Leak

Refrigerant leakage is another reason your central air conditioner is not cooling your house. If you have a refrigerant leak, you need to dial for emergency AC repair. 

The refrigerant transfers from the indoor to the outdoor unit, expanding and compressing. If all is well, you will never have to top up or replace refrigerant because it never runs out.

However, if there is a leak, there will be less refrigerant to absorb heat in your house. This means that your house will remain hot even after hours of cooling.

How will you identify that there is a refrigerant leak?

  • There will be a hissing sound of the refrigerant escaping when you turn on your AC system
  • AC is not blowing cold air or taking an exceptionally long time to cool your house.

If you suspect that your system has a refrigerant leak, stop using your AC system and immediately call HVAC company. A refrigerant leak is dangerous and should only be handled by certified HVAC professionals. Do not try to fix anything if you suspect your leak.

Wrong AC Size

Many home homeowners get the wrong size of air conditioners. Unfortunately, if you have the wrong AC size, you should be searching for “AC installation near me”, as the only solution for this is a complete replacement.

If your central HVAC is not cooling your house, chances are it is undersized. If the temperatures outside are moderate, you will most likely not feel the effects of a bit of air conditioner. However, when the temperatures start to rise outside, your undersized central air conditioner will not cool your house.

Central air conditioners are sized depending on the amount of cooling they can provide. This is measured in BTUh (British Thermal Units per hour). Under normal conditions, you may not notice any issues with the air conditioner(1). However, as temperatures rise outside, your AC may run for long periods and struggle to keep you cool. 

If your AC is undersized, we will help you determine the right size for a replacement. To determine this, we keep the following in mind:

  • the size of your house,
  • quality of construction and insulation in your house.

Give us a call to determine whether the air conditioner in your house is the correct size.

Poor AC Maintenance

Many homeowners ignore annual AC maintenance. And the result would be a poorly functioning air conditioner and deterioration of indoor air quality.

If your air conditioner is suddenly not blowing cold air, ask yourself, “when was the last time I had AC maintenance?”

If your answer was more than a year ago, that is possibly why your indoor air handler unit is not blowing cold air.

AC Freezing up

Yes, AC units are meant to cool your house. They, however, are not supposed to freeze or have a build-up of ice.

If your AC is freezing, you have a clogged or dirty filter or coil. When your AC is freezing, it means that:

  • the evaporator coil is not absorbing any heat,
  • the condensate line is clogged,
  • low refrigerant levels,
  • the thermostat is not correctly set.

Here are signs that you may have a frozen evaporator coil:

  • frost accumulating on the copper refrigerant lines coming from the coil cabinet,
  • Warm indoor air instead of the expected cool air,
  • increased energy costs,
  • excessive condensate drainage close to your indoor unit,
  • Frost build-up on the outer refrigerant tubing or the outdoor condenser unit.

If ice build-up happens, try running your system with just the fan. This should help melt the ice, and the system is back to properly cooling your house.

However, if this does not work, you may have low refrigerant levels. This calls for professionally AC repairs.

Duct Leak

A duct leak is somehow tricky to detect. However, it will show when you start missing in the cold air and when the energy bills start shooting over the roof.

A duct leak means that cooled air is escaping from the ducts into the walls before they reach the vents. Also, heated air is lost through the duct holes during winter.

The solution to a duct leak is getting a professional AC repair that involves a duct seal.

Damaged Heat Pump

Some homes have a heat pump system as their outdoor unit.

A heat pump looks just like an AC unit but has components that allow it to cool or heat your house.

If your condenser has mechanical problems, it will not cool your house. If you have troubleshot all the problems in your central AC and are still sweating inside, you could be having problems with your heat pump.

A professional HVAC technician must repair a faulty heat pump to enjoy a proper cooling process.

Blocked or Clogged Registers (or Vents)

Homeowners often worry about dirty coils and dirty air filters. However, dirty or clogged vents could be why your system is no longer cooling your house.

When there are clogs in the vent, the room with the vents will feel considerably warmer than the rest of the house. If the room in question feels warmer, that is a clear indication of a ventilation problem.

Vents may get blocked accidentally. Therefore, you may want to check them and see if anything may have clogged the vents.

Electrical Issues

Electrical issues are another reason your HVAC system is not blowing warm air.

If your Air condition is not blowing cold air, check to ensure it is plugged in. Is the system plugged in the socket correctly, absorbing heat energy?

Also, you may notice that the cord and the outlet are just fine; the issue could be in the electrical panel. Air conditioners need large surges of electrical power. If you have a tripped breaker and or blown a fuse , your AC unit may have issues.

Besides, if your switches are overloaded, you may want to rectify them.

Clogged Drain

Air conditioners help get rid of moisture from the indoor air.

Therefore, the hose that leads the moisture outside makes a moist and thriving environment for algae and mold. A build-up of these eventually blocks the drain.

You will need a professional AC repair to replace the piping in such instances. We highly discourage you from handling algae and mold on your own.

If you are not ready to replace the pipe, mild bleach can help unclog clogged drains.

AC Repair for AC Unit Not blowing Cold Air

It can be hell for you and your family to stay inside a hot house, with an AC not blowing cold air. You do not want this situation, even for a day on those scorching days.  Luckily, we offer you 24 7 emergency AC repair. Give us a call as soon as you notice a problem. 

First, start by confirming by putting your fingers on your vents. From this, it will be apparent to you whether the system is blowing cold air or not.

The next step is to try and figure out whether it is an issue you can solve or if you need to call for professional AC repair.

If it is a dirty air filter, you can change that if you know how to. You can certainly ensure your AC is plugged in well.

However, if it is beyond that, we recommend that you let a licensed HVAC technician handle it. You do not want to try and fix refrigerant leaks, faulty compressor, duct leaks, mechanical issues, improperly installed AC and wrong AC size.

Give us a call today at HVAC Santa Clarita, and we will be glad to help.

AC Unit Not blowing Cold Air FAQs

AC unit running but not cooling your house is a nightmare we don’t want people to deal with. Unfortunately, it happens to many people. Staying sweaty in a scorching house even for a day is daunting.

There are many possible reasons your AC could not be blowing cold air. And this makes it difficult to point the finger at the problem. 

We answer some FAQs and hope these help you before you go looking online for AC repair near me

Why is my air conditioner running but not cooling the house?

There are quite a number of reasons your AC is not cooling your house. These could be from a blocked or frozen evaporator coil, dirty air filters, mechanical issues, refrigerant leaks or duct leaks.

If you cannot pinpoint the issue, we recommend calling your HVAC professional to go through a troubleshooting process.

How do you fix an air conditioner that is not cold?

There are issues you can solve, and there are issues that are better left to licensed professional HVAC technicians.

However, the first thing you do is check if your system is well connected to the power. If it is, you should consider changing your filters if you have had them for more than a month.

If these two are fixed but still no cold air from your air conditioner, you will need to call a licensed HVAC technician. 

Should I turn off the AC if it’s not cooling?

Yes. If your air conditioner is blowing warm, turn it off and call your HVAC technician. 

Why does the AC give off the cold air and then warm for some time and again cold?

This cycle happens when your expansion valve could be falling apart. The expansion valves lower pressure from the liquid refrigerant, transforming it into gas in the evaporator coil. If you experience this cycle, you will need to replace your expansion valve. 

How do you clean a clogged condenser coil?

First, remove debris from the coil using a soft brush. You can then spray the coil cleaner and let it settle for some minutes. Next, you can use soap and gentle water pressure to clear out any small remaining particles. 

Why does my AC stop cooling after some time?

This is called short-cycling. One cause of short-cycling is a malfunctioning thermostat. If a thermostat detects false temperatures, it will cut short the cooling cycle. Another reason would be a clogged air filter exerting too much pressure on the blower motor forcing it to cut short the cooling cycle. 

Final Thoughts on Ac unit not blowing cold air

We have come to the end of one of the most common HVAC problems (2) homeowners face; AC unit not blowing cold air. 

At this point, we trust that you can quickly troubleshoot and solve simple DIY issues. And even more importantly, you know when to call for professional AC repair. 

Don’t sit in a scorching house waiting for the problem to get out of hand. Give us a call as soon as you notice your AC is not blowing cold air. We will be happy to promptly solve the problem.

call 661-888-0248

Contact us 24/7 today to make an appointment.




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