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Jun 8, 2015

AC Not Working? 5 Things to Check Before you Call a Repair Guy

Whether you have a new air conditioner or a unit that's been dependable for years, many things can go wrong. Fortunately, you can solve these common issues on your own without calling an HVAC technician.

1. Clogged Filters2013-11_climatisation_img_335x250.jpg
Clogged return filters are the most common cause of air conditioning problems. After months of use, dust and dirt prevents air from entering the HVAC system. This can create two problems. First, the strain can cause your air handler to overheat. Second, the evaporator coils can freeze over when there isn't enough warm air in the system. If you experience this problem, change your air filter immediately. Then, run the fan only to give the coils time to thaw.

2. The Unit Isn't Receiving Power
Many HVAC systems have an emergency cutoff switch that's located on the furnace or in a utility room. This switch may have been turned off accidentally or intentionally. If possible, locate this switch before calling a professional. Usually, it looks like an ordinary light switch. If that doesn’t solve the problem check that the wires that link your air conditioner and thermostat have been damaged possibly by rodents or bad weather. Finally, see if the circuit breaker has tripped. Check these things before scheduling repairs.

3. Contactor Problems
A contactor is a delicate switch that controls your air conditioning unit. Problems with this part can prevent your air conditioner from running or cause it to run continuously. This part can fail due to wear and tear, but problems usually occur when ants, wasps or other pests are blocking the contactor. To see if this is causing your problem, turn the thermostat off, and open the cover on your air conditioner. Then, locate the box that protects the contactor. Carefully remove any pests or debris, and replace the cover.

4. Short Cycling
Short cycling is a common problem associated with oversized units, low airflow and equipment that is clogged with pollen, grass clippings and other debris. If the unit shuts off moments after it has kicked on and never cools your home, the outdoor unit is probably clogged with dirt that is obstructing the airflow. If you have bushes growing around your compressor, make sure they are at least 3 feet away from the top and sides of the unit. Then, hose down the unit. For best results, use a coil degreasing agent.

5. Blocked Condensate Drains
Depending on the configuration of your HVAC system, condensation may build up in your attic or inside your home. Condensation on the inside of windows is one sign that your air conditioner isn't removing humidity properly because the drain is blocked. If your evaporator coils are located in your attic, the drain pan can overflow and damage the ceiling. If you have a package unit that's located outside, the moisture can re-enter your home. When it's humid, check the drain pipe to see if moisture is being released. It's a good idea to clean the condensate drain annually by pouring peroxide into the access port or into the drain pan. This will break down algae and deposits that are blocking the pipe.

Electrical issues, problems with refrigerant and mechanical malfunctions should all be handled by a certified technician. If your equipment is still under warranty, make sure that you aren't voiding your coverage by attempting to diagnose problems yourself. If you like fixing things and want to learn more about heating and air conditioning, you can always take HVAC classes from IOT in California or Oregon. Learning a trade can put you on the path to a career that you enjoy.