Our Blog

Common AC Problems – What Should You Be on the Lookout For?


Air conditioning problems can happen when you least expect them, whether the system in your Northern Virginia home is older or a brand-new model. Before you call the professionals, try these tips to troubleshoot the most common A/C problems, and you might just save some time and the cost of a professional visit:

Common A/C Problems

  • Weak Cooling: Often this is caused by a dirty indoor cooling coil, a thermostat malfunction or an airflow issue. If the evaporator coil is accessible, clean it using a soft brush and a vacuum, being careful not to bend any of the cooling fins. If that does not work, check your registers and grilles for blockages and make sure that the thermostat has power and is set correctly. Also, replace the air filter if its dirty or clogged.
  • No Cooling: If the air filter, evaporator and air ducts are clean, and the thermostat is operating properly, the outdoor condensing unit may be blocked or dirty. Clean around the outside of the unit, making sure there’s sufficient space for airflow, about 18 inches, all around the unit. Also clean the condenser coil, using a brush and a commercial cleaner, according to the cleaner’s instructions.
  • A/C Turns On and Off Frequently: Typically, this is a heat-transfer problem caused by dirty coils or incorrect refrigerant levels. Make sure the indoor and outdoor coils are clean, and check the registers for blockages. Also make sure the thermostat is set correctly. Have the coolant level checked by a professional.
  • Compressor/condenser will not run: Make sure the thermostat is operating and that there is power to the system. Reset any tripped breakers and replace any blown fuses. Turn the power to the A/C off for five minutes, then back on. Also check for other safety systems, such as a disconnect switch or pressure switch, and reset them. If these methods do not work, there may be problem with the compressor or its run-capacitor.

If these solutions to common A/C problems have not helped, contact our professionals at HVAC & Plumbing Unlimited Heating & Air Conditioning for assistance in Fairfax or the surrounding area.

Image Provided by Shutterstock.com

HVAC Unlimited Inc.
On time, courteous, very competent.
Nancy - Manassas, VA
Ask about our special financing for 3 years with approved credit!
Accreditations & Affiliations