Fixing Defective Air Conditioners
The various types of air conditioners will have different reasons for blowing warm air instead of cold. As such, each type will also have differing fixes and methods. We outline those differences below.
Home Central Air Conditioner not Blowing Cold Air
For home central air conditioners starting cold and then blowing warm air is generally an icing or freezing issue. The system will work correctly until the ice has time to form, resulting in warm air coming through the vents.
If the system starts warm and never becomes cold, then the issue can be a myriad of things. The most common, though, is blocked airflow from a clogged air filter, or the compressor is not working.
If you cannot quickly and easily locate the cause of the warm air, it is always best to call in an HVAC technician. However, you should always make a few checks yourself. First, you want to change the air filter to ensure the intake airflow is unobstructed.
Next, you can check the thermostat and condenser unit. Look for icing of the lines, an overheated compressor, and a bad fan motor. If these all check out fine, open the access panel to the evaporator unit and look for ice on the coils or a blower fan motor not working.
Mini Split Air Conditioner not Blowing Cold Air
If you cannot diagnose the problem, or it turns out to be a bad fan motor or icing of the lines, it is time to call in a professional for repairs and further inspection.
RV Air Conditioner not Blowing Cold Air
Car Air Conditioner not Cold
Why My Air Conditioner Is Not Blowing Cold Air
With the temperatures hitting an all-time high, having an AC not blowing cold air is a homeowners worst nightmare. You can imagine how terrible the situation at your home can get when the temperatures keep rising, yet you can do nothing about it except looking for an AC repair service. There are many reasons why the AC can fail to cool the house. You need to figure out the exact cause of your AC failure and have it corrected to continue enjoying a cool home environment. You shouldnt despair weve rounded up several reasons that can cause an AC failure and what you should do to get it blowing again.
Air Conditioner Wont Blow Cold Air
If your AC system turns on but doesnt blow out cold air, ensure all the vents are open and the thermostat is set properly. If these arent the problem, check the air filter. If its clogged with dirt or other debris, you wont get any air flow. Since the clog may cause the evaporator coils to freeze, the ice and frost will clog the air flow even more. If thats the problem, clean the filter with a soft brush, mild soap, and water. Clean and change your filter often to avoid that problem in the future. You may also have a problem with the fan or fan motor. If the fan turns easily, you may have a problem getting electrical power to the motor or a leak in the refrigerant line. In these cases, youll probably require a qualified HVAC technician to come inspect the unit.
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Troubleshooting Your Aircon If Not Blowing Cold Air
1. Make Sure The Thermostat Is Set To Cool
On most occasions, you do need to exert yourself much to fix an aircon that is not blowing cool air. Prior to calling the technicians, make sure that it is set to âcool,â and also that the temperature of the room is low enough to switch on the unit.
2. Inspect Circuit Breaker Box
If the problem of your aircon is not because of the thermostat, then you ought to verify the circuit breaker box. Most air conditioning units come with two parts â the indoor unit, and the outdoor unit. If the outdoor device isnât powered, the indoor unit will not be able to supply you with cold air. Try resetting any tripped circuit breaker and wait for some time to check whether the problem occurs again. If the problem does not go away, it’s time for you to seek the help of a professional expert.
3. Clean Dirty Aircon Filters
Dirty aircon filters will make the device work harder plus less effectively. As a result, there is the possibility for your electricity bills to go up and you wonât get the cold air you desire. Make it a point to wash the filters at least once every month.
4. Check If Thereâs Ice Build-Up In The Aircon
Why My Ac Is Not Blowing Cold Air

Reliable cool air is crucialespecially if you live in a hot, humid climate where temperatures reach into triple-digits. The last thing you want to walk into after a long day is a hot, stuffy, and downright miserable home.
From dirty air filters to frozen evaporator coils, things can go awry with your air conditioner when you least expect itand even the smallest problems can cause your energy costs to rise. Luckily, we can pinpoint a few issues that could lead to your systems malfunction. Check out these five reasons why your AC is not blowing cold air and keep reading for one guaranteed way to fix them all.
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What To Do If No Air Is Coming Out Of Vents In One Room
Sometimes, you may experience no air coming out of vents in one room in your house. If this happens, make sure that the particular rooms air vent is fully open and not accidentally closed or left partially open. Another reason for the room to experiences no airflow may be that its too far from the unit and this implies that you have an underpowered AC. Try closing some air vents in bathrooms, closets, and hallways to see if you get better airflow to the affected room.
Heres How To Set Your Acs Thermostat
The temperature you choose on a day-to-day basis will depend on where in the country you live, what type of insulation you have in your home, and what time of year it is.
In the summertime, when temperatures outside are warm to hot, you should set the air conditioner unit at a higher temperature than that same AC would need if located somewhere much colder. For example, if your house frequently reaches 80 degrees Fahrenheit on a hot summer day, you would set your thermostat to at least 78 degrees Fahrenheit.
Running your air conditioner in this manner will help the AC unit maintain a home temperature thats comfortable for most people throughout the day. Its more effective to do this than trying to cool down an entire house in just one hour or so once you get back inside from the hot afternoon sun.
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Why Is My Central Ac Running But Not Blowing Air
Its that time of the year the heatwave is on your neck. You cant do anything but feel disappointed with your central AC running but not blowing air.
If your central AC is running but not blowing air, your units fan capacitor is bad or experiencing failure. When working properly, the capacitor sends an energy surge to your ACs outdoor and indoor fan motors and compressor running, helping blow cold air into the room. Clogged filters, dirty condensers, frozen evaporator coil, and faulty thermostats can also cause problems.
These are some of the things you can check when you experience this issue but there are several other things you can look at as well.
So, in this article, we dive deep into whats causing your central AC not to blow cold air and DIY steps you can take to deal with the problem.
Clogged Filter Switching Off The Motor Preventing Cooling Coil To Lower Air Temperature
Every ounce of air that the air conditioner outputs have to go through the air filters. That means that the total airflow can be restricted if the filters are clogged. If the airflow is restricted, many AC parts like compressor, motor, fan, and so forth start to overcompensate to generate more airflow .
In short, dirty filters might sound like a small thing but it leads to serious AC issues. Thats why many air conditioners have a built-in switch that shuts the AC unit down if the filters are too clogged. This will, obviously, result in the air conditioner not working properly and not delivering the cool air output.
In some cases, it makes sense to clean the filter. In more cases, the best way of action is just to replace the clogged filters. MERV 5-12 filters used in AC units are fairly inexpensive you can get a pack of 6 filters for about $60 .
Note: Dirty filters might shut off the compressor before the fan. That will lead to your air conditioner not blowing cold air while still running.
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Reasons Your Air Conditioner Is Not Blowing Cold Air
Is your air conditioner not blowing cold air? This can be an extremely uncomfortable and frustrating experience for homeowners. To help you diagnose the issue, we have compiled a list of issues that can cause your air conditioner to circulate warm air in your home. If you need assistance with an issue, our team of technicians are available 24/7 to help you find a solution to your problem.
Our expert technicians are here for you
Ac Unit Has Experienced Normal Wear And Tear
Unfortunately, AC units dont last forever. The average lifespan of a central HVAC system is 15 to 20 years. If your unit has been working to cool your home for more than two decades, it shouldnt come as much of a surprise that it isnt working like new. Normal wear and tear can cause the unit to operate less efficiently and signal that it may be time to install a new system.
The good news is that if your central AC is not blowing cold air, there is probably an easy fix. Restoring your unit and achieving a cooler and more comfortable indoor environment may be as easy as changing your air filter or resetting a circuit. Even more complex fixes that require professional assistance are usually relatively easy for someone with the right skills and experience. Once your problem has been diagnosed, it wont take long to return your home to normal and enjoy a cool oasis away from the summer heat.
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Know When To Call A Professional Hvac Contractor
If youve worked your way through the above troubleshooting efforts and preventative maintenance measures but still find your air conditioner is working but not cooling your house, it may be time to call in the reinforcements.
The best course of action we can recommend is to assess the situation of the AC not cooling the house, determine whether the problem at hand is one you can apply a DIY solution to or one you should call for some backup. Then get to work or start dialing. Your house will be a much happier home when the air blows cool from your vents!
Ac Is Not Cooling To Thermostat Setting

Be sure that your thermostat is set properly. If your power went out recently, keep in mind that this may reset your thermostat settings! Make sure that its set to COOL and not ON, because only the fan would run.
You would be surprised how many issues can be traced back to a faulty thermostat. The batteries can die, the circuitry inside can malfunction, and a host of other failures can happen without drawing a lot of attention. A thermostat failure isnt as dramatic as a sudden, loud metallic noise or grinding.
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Blocked Or Undersized Return Vents
Your return vents should be unobstructed.
Take a look at your return vent . Is it closed, or is anything blocking it? If so, that could explain why your AC isnt blowing hard.
Additionally, if your return vents were sized too small for your homes air circulation needs, that would also create low airflow.
Why Is My Air Conditioner Not Cooling My House
If you find your AC not cooling your house, then you’ll want to find the solution as soon as possible. So we will start by looking at the easiest solutions first.
Check Your Thermostat
If your AC is running but not cooling, then check your thermostat settings. It’s possible that someone changed the temperature or fan settings on the thermostat. Make sure it is set to “cool” and not to “fan”. If the settings all look correct and you’re continuing to have problems, then you should proceed to the next step.
If you have a Nexia thermostat, you can connect your local service company to the thermostat so they have access to some internal diagnostics. Contact Pro-Tech to find out if your thermostat is connected and if we have access to any diagnostic information.
Change Your Air Filter
Your AC may not be cooling due to a clogged or dirty air filter. Locate your air filter and visually inspect it. If you notice it has a decent amount of dirt or debris, then change your air filter.
A standard 1 inch air filter should be changed about once every month. Changing the air filter not only gives you cleaner air, but it also ensures the proper air flow in your AC system. If the air filter becomes clogged it may be the reason your AC is not cooling your home.
If the air filter appears to be clean or your air conditioner is still not cooling your home after changing the air filter, then move on to the next step.
Check For Clogged Coils
Frozen Evaporator Coil
Leaking Refrigerant
Air Conditioner Leaking Water When Turned Off
If your system is low on refrigerant or has a dirty filter, the system may freeze up when its working. After you turn it off, the ice melts, causing it to leak water. Dont risk water damage from your air conditioner leaking water on the floor or ceiling. If cleaning your filter doesnt help, dont turn your AC system on again until you have identified and fixed the problem. As with outside leaks, you may have a blockage or a broken condensate pan.
What To Do If Your Air Conditioner Is Running But Not Cooling Your House
Its no fun when the air conditioner doesnt work, however, it happens. And it wont be in the middle of winter as it happens. It will be the hottest day of the year, and no matter how low you set the thermostat, the air conditioner will not blow cool enough air.
The condenser compressor outside your house is just part of an air conditioning system. An indoor air handler unit , an evaporator coil, air filter, thermostat, and copper tubing that link the indoor and outdoor systems are all common components of split-system air conditioners.
So, to the debate, Why isnt my air conditioner cooling the house? There are a few options. But dont be concerned. Only because your system isnt cooling doesnt mean you have to spend a lot of money on AC upgrades or a new system.
The majority of homeowners are capable of doing simple troubleshooting and will be able to fix the problem. There are times, though, that youll need to contact the nearest HVAC company for reliable air conditioner support.
There are a number of reasons why your air conditioner could be working but not dropping the temperature in your home, ranging from basic problems like an improperly set thermostat or a dirty filter to more complicated situations requiring part replacement.
Check Your Circuit Breaker
Breakers trip all the time but when your AC isnt blowing cold air, your mind probably presumes the worst.
Your air conditioning connects to two circuit breakers one for the outside unit and another for the inside.
If the outside breaker trips and the inside breaker is still functioning, the air cant be cooled.
Reset the breaker, but if it happens again dont be too fast to reset it as it could cause damage to your AC.
Why Is My Ac Not Blowing Cold Air
There are many reasons your AC might not be cooling your home properly. The solution could be as easy as flipping a switch on your thermostat, cleaning a dirty air filter, or clearing debris away from your outdoor unit. There are also more complex problems that may need the help of a professional. Here are a few ways you can troubleshoot the problem.
Clogged Condensate Drain Line
You know how we mentioned above that the water condensed from warm air gets filtered out through condensate lines? Over time, all this humidity in such an enclosed space will cause a sludge of mold and mildew to build up. Add dust and a couple insects or two, and you can end up with a clogged drain.
You can prevent this from happening by flushing them regularly with distilled white vinegar. To find them, walk outside your home, towards the air conditioners condenser unit. Close to it, on the exterior wall of your home, youll find a pipe dripping water outside. Thats your condensate line.
If you havent been providing it with regular maintenance and theres already a clog, youll need a wet/dry vac and a DIY pipe to clear it. for a video tutorial on how to do it.
For more information, check out our blog: How to Unclog Your AC Condensate Drain Line in 6 Steps
Why This Works So Well

Heres the idea behind this rule of thumb for setting your AC units thermostat. It allows you to control the temperature in each room by simply using a fan. Youll save money on the power bill when youre not constantly turning the AC on and off if things start getting too hot or cold.
If there are rooms in your house where it gets too cold or hot no matter what the AC units thermostat is set to, you can use cheap box fans in these rooms instead.
If there are areas of your house that feel warm all year round, its probably time to look into getting better insulation for your home. Insulation keeps cool air inside during the summer and warm air inside during the winter. Its a great way to save energy when it comes to cooling your home in warmer months and heating it in colder months.
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Proper insulation is especially important if you live in an area where summers are typically hot or winters are typically cold, without not much of a transition season in between.
If your AC is not cooling, always check how well youre regulating it via the thermostat first.