As the temperatures in Boston begin to heat up, it’s natural to seek refuge in your home. And that’s especially true if you have central air conditioning. While it’s your hope that your AC works as intended all summer long, there may come a point when you realize that it’s not blowing cold air. If this happens, turn your system off and begin the diagnostic process.

Here are some of the most common reasons why a central AC unit may stop blowing cold air:

Dirty Air Filter
Remember, just because your air filter is located in your furnace doesn’t mean it has nothing to do with your AC system. Excess debris can reduce airflow, which can make your home feel warmer. If it’s been longer than 90 days since you changed your air filter, examine it and swap it out for a new one.[i] From there, if you once again have cold air coming from your vents, you’ve found the problem.

Your Thermostat
Your thermostat is the “brain” of your central air conditioning. Without this, the system wouldn’t know what to do. The first thing you should do is check the settings. Have you turned your thermostat to cool?
From there, make sure you’ve set the desired temperature lower than the current temperature in your home. So, if your thermostat is showing that it’s 74 degrees inside, set it at 72 and see what happens. If your system comes on, you’ve found your problem.

Air Duct Leak
One of the most common problems with central AC is air duct leaks. Since you can’t see or feel these leaks, as they occur inside walls and/or under floors, it’s a challenge to detect the problem and make a repair. When cool air escapes through a leak (or several leaks), it doesn’t reach its intended destination. As a result, airflow in some rooms of your home will be reduced or cut off entirely.

Refrigerant Leak
Without refrigerant, your AC is unable to cool your home. So, if there’s a leak, you can expect the air to feel warmer than usual. This isn’t a DIY repair, so you’ll want to consult with an experienced HVAC professional.

Tripped Circuit Breaker
As you know from the cost of your electric bill, your central AC system uses a lot of electricity.
Depending on the setup of your electrical system and HVAC, a tripped circuit breaker could be the cause of your problem. If the insider breaker is functioning but the outside breaker is tripped, your AC system will run, but the air won’t be cooled. Resetting the breaker may be all you need to do.

An air conditioning system that doesn’t blow cold air is useless. If your air is warm or not quite as cold as you’re used to, it’s time to find out why. If you require any assistance, don’t hesitate to contact us. We can quickly diagnose your problem and discuss repair options.

DIY Air Conditioning

Skip to content