If you put your hand in front of your air conditioning registers and feel barely a trickle of cool air coming out, there’s definitely an air flow problem.

Even worse than not enough cold air, you might actually feel warm air coming out of the registers.

Are some rooms too warm while others are freezing? Temperature variance is another common symptom of air conditioner problems caused by inadequate or improper air flow.

If you experience odd unexplained symptoms like doors opening and slamming all by themselves, whistling noises and random drafts of air, you might think you have a resident ghost. In reality these symptoms are caused by unbalanced air pressure, which can happen as a result of air flow issues.

When air flow issues are neglected for too long, the strain on the system can lead to compressor failure. The compressor is the heart of the system and an expensive part to replace. If it fails, there’s a good chance you’re going to need a new air conditioner.

The air filter’s job is to keep dust and debris out of your HVAC equipment (not the air), like out of your evaporator coil and blower wheel. You’d be amazed how much builds up on there in a very short time. When that dust builds up inside the air conditioner, it causes wear and tear on the parts, and the clogged filter prevents enough air from flowing through the system to keep it working properly. Remember the regular HVAC system return filter is not intended for house air purification processes, but unit cleanliness. For air purity, these are done by adding a air scrubber, UV lights, or other filtration systems.

In cooling mode, your air conditioner’s blower fan moves the air through your conditioned space over the evaporator coil to transfer heat outside, and the condenser fan that moves outside air across the condenser coil to help expel the collected heat outside the building. If either of those fan motors get covered with debris (which can happen if the air filter is clogged or if you’ve neglected maintenance) the fan speed dwindles over time until one day it locks up.

You’re spending a lot of money for cooled air, so the last thing you want to do is let it get wasted. Isn’t that why you’re always telling people to keep the doors and windows closed? Yet that’s what happens when you have holes and breaks in your ducts or connections. Your expensive cooled air leaks out and never makes it to the desired areas of your space.

Have you recently replaced your air conditioner with a larger size tonnage? If so, your ducts may be too small to handle the volume of air being pushed from your new air conditioner. Another major problem is poorly designed ductwork with runs that are too long to successfully carry the air to the space to be cooled, or the trunk supply has ducts at the end of the plenum, reducing static pressure.

Closing too many vents can disrupt the proper pressures of the refrigerant and static pressure in the ductwork. Make sure vents are clear and open as much as possible.