Why is the AC Running But Not Blowing Air?

Nobody wants to schedule an AC repair only to find out that the problem is a small thing you could have fixed yourself. It’s possible for that to happen when your AC is running but not blowing air, or only blowing a little air.

Keep reading to learn about a couple of things you can check before calling for AC repair, as well as the causes that require help from the professionals.

2 things to check when your AC is running but not blowing air

1. Is the system actually running?

You might assume your AC is on (but not blowing air) because you didn’t turn it off. But first check all thermostats to make sure a family member didn’t turn them off. 

It’s also possible for a blown fuse to turn off your system, especially if you just had a power failure. So check your fuse box next, and reset it if you find a fuse switched off. And then double check to make sure your AC unit is actually running. 

2. Is there a blockage?

Blockages can restrict the air flow coming from your AC registers. This could be the problem if your AC is running but not blowing air from one specific register. 

First, make sure the register damper is open. Then remove the register cover and check for visible dust and debris clogging the duct. It’s also a good idea to check your AC filter and see if it’s clogged with dust. If so, get a new filter and replace it. 

Also, if you have a ducted split central air system or ductless mini-split system, check your outdoor unit to make sure it’s not clogged with leaves or debris.

If you haven’t found the problem yet, you’re looking at a mechanical issue that requires help from an expert HVAC technician. 

IMPORTANT: Should I turn my AC off if it’s not cooling?

At this point, YES you should turn it off while you wait for help to arrive. Keeping the system running could cause additional damage.

AC equipment problems that require professional repair

If you weren’t able to find the problem with the checks listed above, then there is a problem with your AC equipment that’s going to require professional repair. Here are some equipment issues that can lead to AC running but not blowing air:

Capacitor

A capacitor is a small electrical component that can fail and cause a fan motor to stop running and blowing air. It’s a quick fix for a trained HVAC technician, but not a task you should attempt yourself. 

Computer module

Modern air conditioners have computer modules that control the compressor and fan operation. If a computer module fails, you’ll need a technician to replace it.

Fan motor

Like any other motor, a motor that controls an AC fan can burn out. Without the fan, you’ll have no air blowing from your AC registers. Again, this problem requires a professional to replace the fan motor. 

Internal duct clogs or leaks

If your split AC is running but not blowing air, the ducts may be clogged inside your walls and ceilings where it’s impossible for you to see or clear the debris yourself. Also, the insides of your ducts can develop holes or cracks, causing air to leak out inside walls and crawl spaces instead of blowing into your rooms. 

In this case, you’ll need professional duct cleaning and/or duct repair. The experts have special cameras that allow them to see deep inside your ducts, and tools to vacuum out debris. If your technicians find holes or cracks, they will need to replace the leaking ducts.

Thermostat

Problems with your thermostat’s sensors or its wiring can cause the system to get the wrong signals and not blow cold air when needed. Your technician may need to replace your thermostat. 

TIP: If you’ve still got old, manual thermostats, this is a great time to upgrade to programmable ones. You will find them very convenient! You can set schedules and control your AC from your phone.

Coil or compressor 

If your AC is not blowing air AND not cooling, then you may have a more serious problem with your AC coil or compressor. 

Your air conditioner’s evaporator or condenser coil may have developed holes due to corrosion and is leaking refrigerant. When that happens, the system’s cooling capacity gradually decreases until it’s not cooling at all. Depending on the age and condition of your equipment, your technician may be able to repair or replace the coil to restore your air conditioning.

The compressor is the heart of your air conditioning system. If it fails, the refrigerant no longer flows through the system, causing a loss of cooling power and airflow. Compressor failures happen for many reasons. In some cases, the compressor can be replaced, but often the entire unit will need to be replaced.

Call Bruni & Campisi NOW if your AC running but not blowing air

Don’t risk further damage to your system: call now and we’ll get it taken care of FAST. With our 24/7 service, we do the work when it’s convenient for you. And you can trust our experts to get the diagnosis right and perform quality work. 

Call us at (914) 292-0498 or schedule your appointment online.

Bruni & Campisi provides 24/7 emergency service, installation, and maintenance for plumbing, heating, air conditioning, and generators in Westchester, Fairfield, and Putnam Counties. We also offer sewer cleaning, and chimney cleaning. With our 40+ years of experience and training, you get the quality service you need.