Having your air conditioner start blowing warm air can be frustrating. It’s especially a concern in Phoenix, as your house can get dangerously hot if your AC isn’t working and put everyone at risk of heat stroke. This issue is more common than you may think and can happen for a variety of reasons, some of which you can quickly fix yourself. In this article, we’ll look at the different reasons, how to troubleshoot the problem and when you should call a professional to have your AC system inspected.
Common Reasons Your AC Is Blowing Warm Air
Warm air from an AC system can be related to something simple, like using the incorrect thermostat settings or having a dirty air filter that’s blocking off airflow. A refrigerant leak can also hinder performance because an AC system can’t cool effectively if it’s low on refrigerant. If the refrigerant level is much too low, it can lead to your air conditioner not cooling at all. Low refrigerant will also often lead to the evaporator coil freezing, which also prevents the system from being able to cool.
Electrical issues, like a blown fuse, a bad capacitor or a faulty relay switch, can cause an AC to blow warm air by preventing the compressor or fan in the outdoor unit from running. One of the most common issues that will cause an AC to blow warm air is a dirty evaporator coil or a dirty condenser coil due to a lack of maintenance.
How Thermostat Settings Can Cause Warm Air
One of the most common answers to the question of why your AC is blowing warm air is that you’re using the incorrect thermostat settings. One thing to check when this issue arises is that you don’t accidentally have your thermostat set to “heat” instead of “cool.” You should also make sure that the fan setting on the thermostat is set to “auto.” This mode will continue running after the outdoor AC unit shuts off and just start circulating warm air around the house. There’s also a chance that your thermostat is malfunctioning or not calibrated correctly, but this isn’t something you’ll be able to check for on your own.
Impact of Dirty Filters & Coils on Cooling Performance
A dirty air filter greatly decreases cooling performance, leading to longer cycling and a decrease in efficiency. The issue is that a dirty filter is restrictive, meaning it reduces the amount of air the blower can draw into the indoor part of the AC system. Not only does reduced airflow mean that the system can’t remove air from the house as quickly, but it also means that the system circulates less cool air around the house. In many cases, the result is that you have weak airflow in some rooms or warm air blowing out of some of your vents. The best way to prevent these issues is to replace your AC air filter every two to three months.
Dirty coils are also a major contributor to poor cooling performance. The evaporator coil allows an AC system to remove heat from the house, and the condenser coil enables it to release this heat outside. If either or both coils are covered in dirt and dust, it prevents this heat transfer process from working effectively. That means the air blowing out of your vents will often be around the same temperature or only slightly cooler than the current temperature in your house.
Dirty filters and dirty coils also lead to increased strain. Over time, this strain can cause the system to break down or shorten its lifespan.
Refrigerant Issues & What They Mean
As an AC system ages, it can sometimes develop a leak in one of the refrigerant lines or one of the coils. A small leak may not have much of an effect on performance or lead to the system blowing warm air, except on extremely hot days. However, at some point, the refrigerant level will get so low that you’ll start to notice frequent issues, like warm air or ice on the refrigerant lines due to the evaporator coil freezing up. Another issue to watch out for is a hissing noise coming from the indoor or outdoor part of the system, as this is usually a sure sign of a refrigerant leak.
If you suspect your AC is low on refrigerant, we definitely don’t recommend DIY refilling. One reason is that you can cause major damage or destroy the system if you don’t use the right type of refrigerant or add too much. Doing any DIY work on your AC system can also automatically void its warranty.
When to Suspect Electrical or Mechanical Failures
One issue that almost always indicates an electrical problem, such as a blown capacitor or faulty wiring, is if your AC keeps tripping the circuit breaker. If this happens, it’s important to leave the breaker off and call for an inspection. In terms of mechanical problems or failures that can lead to warm air, the main things to watch for are the outdoor unit not running or the fan not spinning when the unit is on.
How to Troubleshoot a Warm Air Issue at Home
By following these AC troubleshooting tips, you may be able to resolve this problem yourself before calling for professional help. The first things to do if your AC is blowing warm air are to check the thermostat settings and replace the air filter. You should also check that the circuit breaker isn’t tripped. The blower inside your house is usually on a different circuit than the outdoor unit, meaning it may still run and blow warm air if the outdoor unit can’t turn on because its breaker is tripped. You should also make sure that the outdoor unit isn’t clogged with debris and check for any ice on the lines. If you see any ice, you’ll need to shut your AC off for a few hours until the evaporator coil thaws.
When to Call Action Mechanical for AC Repair in Phoenix
If you’re still experiencing frequent issues with warm air after troubleshooting the system, it’s a sure sign that you need professional help. It’s also essential that you have an experienced technician inspect your AC as soon as possible if you notice any signs of a refrigerant leak or any electrical issues. Other issues to watch out for include frequent cycling, loud noises or your AC shutting off too soon. If your system is more than 10 years old and not cooling properly, scheduling an inspection can quickly help you determine if it’s time to install a replacement.
Trust Action Mechanical for Fast, Reliable AC Repair
Action Mechanical HVAC in Phoenix is always here to help if your air conditioner isn’t cooling or you’re experiencing any other problems. Our experienced HVAC technicians can fix almost any problem you may encounter, and we’re available 24/7 for emergency AC repair services and diagnostics. No matter what the problem is, we’ll provide you with honest recommendations as to the best way to fix it. We’re committed to providing quality air conditioning services at fair prices and will work to restore your home comfort as quickly as possible.
To schedule service and get help getting your AC cooling effectively again, contact the experts at Action Mechanical today.
