Here’s How to Troubleshoot Your A/C

Here's How to Troubleshoot Your A/CYour air conditioner is a complex system of motorized parts, electrical components, refrigerant, fans, and more. If one part is too dirty, out of whack, or has simply gone kaput, your A/C won’t operate efficiently or, perhaps, it won’t work at all. Try these troubleshooting tips before you call your HVAC contractor.

Unit Doesn’t Run

The first component to check if your A/C isn’t running at all is the thermostat. Make sure it hasn’t been turned to HEAT accidentally. Adjust the temperature five degrees below the displayed temperature. If your A/C still doesn’t turn on, look inside the circuit box to see if a breaker has tripped.

Unit Runs but Not Cooling

It can be frustrating and perplexing when your A/C is running but it’s not blowing out cool air from the vents. There may be dirty components or obstructions that are making your A/C work too hard and unable to keep up with the cooling load.

Journey outdoors and take a look at the unit next to your home (i.e. in a split-system A/C). Remove any obstructions to airflow, such as tall grass and debris. If the condenser coil inside the unit doesn’t receive ample airflow, it won’t be able to cool.

The condenser itself could be dirty enough to block heat transfer — especially if you haven’t scheduled professional maintenance this year. Use a can of spray-on foaming cleaner. Let it soak in according to the instructions and spray off with a garden hose. Make sure power is turned off at the thermostat and circuit breaker.

Professional HVAC Help

Professional preventive maintenance is essential for keeping your A/C running efficiently. This saves you energy, reduces system wear, and keeps your San Marcos home comfortable until summer’s end. Moreover, regular service helps prevent expensive and unnecessary malfunctions, which always seem to occur at the hottest and most inopportune times of the year.

If you are unable to resolve your air conditioner issues, contact us at Sherlock Heating & Air Conditioning, Inc. Since 2002, we’ve worked hard to provide the best HVAC services for homeowners in North County and the greater San Diego area!

Our goal is to help educate our customers in the greater San Diego and San Marcos, California area about energy and home comfort issues (specific to HVAC systems).

Related Posts


  • Since blocked airflow can cause my AC unit to be unable to blow cold air, should I also check my air filter if I have this issue? I try to change it often, but sometimes forget and think that it might be the cause of a lot of my problems. It also doesn’t help that I have a dog and his hair often clogs the filter.

    • Hi James, our apologies… this comment got buried somehow and we missed it. Yes, dog hair can certainly be a factor in needing to change your filter more often. Set up an appointment reminder in your phone or email calendar to remind you to check monthly and go from there.


Write a comment