It’s May, and chances are that you’re already getting some use from your air conditioning system in Wilmette, IL. It may be only a few days during the week for short stretches—we aren’t fully done with the cool weather yet—but it will be enough for you to tell if something major is wrong with the air conditioner. For example, you’ll know when the air coming from room vents isn’t cool when the AC is running.
Obviously, a cooling system that doesn’t actually cool is not much use to you. It’s just acting like a big fan, and that doesn’t help when temperatures climb. There are a number of possibilities for why an air conditioner will lose its cooling power. Some are simple errors that you can correct yourself. Others are more complicated and will require HVAC technicians to diagnose and correct them. And some are serious trouble that place your AC in danger of a major failure, possibly even an early replacement, unless professionally fixed as soon as possible.
Here are 4 reasons for your AC only sending out warm air and what to do about them:
ONE: Incorrect thermostat settings
You might think this is too obvious. However, more than once we’ve gone on service calls and found the trouble was someone else in the house changing the thermostat settings (or just fiddling around with them). If the thermostat is set too high or to “fan only” mode, the AC won’t provide cooling.
TWO: Tripped circuit breaker to the outside unit
If the circuit breaker to the indoor unit of an AC trips, the fan won’t turn on at all, a major warning something is wrong. But if the breaker for the circuit to the outdoor unit trips, the indoor fan and other components will still run, but there won’t be any cooling because the compressor outside isn’t running. Check to see if any circuits have tripped in the electrical panel. Reset them and see if this solves the trouble. If the circuit repeatedly trips, call for professionals to investigate.
THREE: Leaking refrigerant
Now we’re getting to the more serious troubles that require HVAC repair technicians. Refrigerant is essential for an AC to remove heat from the air and provide cooling. Refrigerant won’t run out—but it can leak out, and this is a common trouble in air conditioners around the middle of their lifespan (4 to 6 years). When refrigerant levels drop, the AC can lose its cooling ability. Worse, this places the compressor in danger of overheating and burning out, which is a big repair and often a reason to replace the entire air conditioner.
FOUR: Stuck compressor
The compressor is the heart of an AC; it places refrigerant under pressure to start the cooling cycle. If the compressor stops working, there won’t be any cooling. A compressor can become stuck because its motor burns out, its start capacitor fails, or dirt and strain on its moving parts cause it to wear out. Only professionals are qualified to work on broken compressors, and you’ll want them on the job in a hurry to prevent more serious repair issues.
Frequently Asked Questions
Question: Why is my AC running but not blowing cool air?
Answer: Your AC may be running without cooling because of incorrect thermostat settings, a tripped breaker for the outdoor unit, a refrigerant leak, or a compressor problem. Some causes are simple to check, but refrigerant and compressor issues need professional HVAC service to prevent larger damage.
Question: What thermostat settings should I check if my AC is blowing warm air?
Answer: Start by making sure the thermostat is set to “cool” and that the temperature is set lower than the current room temperature. Also check that it is not set to “fan only,” because that setting can move air through the vents without actually starting the cooling cycle.
Question: Can a tripped circuit breaker cause my AC to stop cooling?
Answer: Yes, especially if the breaker for the outdoor unit has tripped. The indoor fan may still blow air, making it seem like the AC is working, but the outdoor compressor will not run. Reset the breaker once, but call a technician if it trips again.
Question: How does low refrigerant affect an air conditioner?
Answer: Refrigerant allows your AC to remove heat from indoor air. If refrigerant leaks out, the system can lose cooling power and may place extra strain on the compressor. Low refrigerant is not a normal maintenance issue, so a technician should find and repair the leak.
Question: Is a bad compressor the reason my AC is not cooling?
Answer: A bad or stuck compressor can stop the cooling cycle completely because it is responsible for pressurizing refrigerant. Compressor problems may come from motor failure, a bad start capacitor, dirt, or wear. This is not a DIY repair, and quick service can help prevent more serious damage.
Rely on our technicians—we offer 24-hour emergency service—when you have an air conditioner that isn’t doing its job.
Malek Heating & Cooling has served the Chicagoland area with exceptional AC repairs since 1998.