Home & GardenInteriorsVentilationTroubleshooting Your Central Air Troubleshooting Your Central Air Split-system central air conditioners, used with forced air furnaces, take hot air from the house and blow it through an evaporator coil located in the top of the furnace to cool the air. The cooled air circulates throughout the house via the heat ducts then returns to the furnace as warm air to be cooled again. Central air conditioners can work for years without problems if properly maintained and serviced annually. If they aren’t working properly, call a trained technician. But before you phone, see if the problem is caused by something else. The unit stops working If you have your system inspected and cleaned annually, it should run without any trouble. However, if it stops working completely and you aren’t sure why, troubleshoot before calling a pro: Check the circuit breaker or fuse box to find out whether the unit has power. Check the fuses in the disconnect box located outside, near the condenser, to make sure there’s power.

Replace or clean the furnace filter. If the condenser coils are coated with dust or debris, use a garden hose to wash them off. If the air conditioner still won’t work, make the call. A technician may have to recharge the refrigerant. The unit won’t quit running If the air conditioner runs constantly, here’s what to do: Turn up the thermostat. If you set the thermostat a few degrees higher, you will save energy and a lot of money when it comes time to pay your electric bill. And your significant other won’t have to complain about wearing a sweater indoors. Take the cover off the condenser and find out whether anything is blocking the air flow. Vacuum the interior of the condenser, and then flush it with a garden hose. If the fan blades are bent or dirty, straighten them out and/or clean them. While the cover is off, oil the motor on older air conditioners. (Newer units are sealed and cannot be oiled.) Take off the plastic covers — there should be two — and put a couple drops of lightweight oil, such as 3-in-1, into each.

Check the furnace filter and blower to see whether they’re blocked. Use a vacuum cleaner to clean dust and dirt on or around the blower. Replace the filter if necessary. The unit freezes up If the high pressure lines from the condenser to the furnace or the evaporator coil in the top of the furnace are iced up, then shut the system down:where can i buy a window ac unit Either turn off the breaker in the panel or pull the disconnect switch outside at the condenser.ac and heater will not turn onYour system is probably low on Freon and needs to be recharged.ac unit replace cost Water pools under the evaporator When there’s water under the evaporator at the base of your furnace, the drain is probably clogged.

You can clear it, but it’s probably easier just to replace the whole thing. If you want to try clearing it, however, here’s what to do. Take off the trap, and if it’s PVC (plastic) you can cut the pipe to remove it. Pour a vinegar-water or bleach-water solution (1 to 10 parts) into the drain. That will help remove debris and algae. If you have flexible tubes, take them off and clean them by pouring the solution through them. You can also run a wire through the tube to scrape the walls. Do it gently so you don’t poke a hole. Reassemble the tubes and trap.When good condensate drains go bad, property damage may result. Central air conditioners produce something other than cool comfort: water, lots of it. Because dry air holds less heat energy, humidity extraction is a critical part of an efficient air conditioning process. When the air conditioner blower pulls warm household air through the frigid passages of the evaporator coil, the cooling effect causes water vapor to condense out of the air rapidly.

Condensation drips down into a collector pan under the coil and is conveyed through a drain line to a household sewer connection. Things that might go wrong in the condensate drain system include damaging leaks, bad air quality, toxic mold growth, and even a complete air conditioner shutdown. Leakage And Overflows The wet, warm environment of a condensate collector beneath a central air conditioner evaporator coil is a perfect algae breeding ground. This biological growth may migrate into the condensate drain line or the drain trap and form a blockage. Condensate overflow due to a blocked drain may be caught by an overflow pan beneath the air handler, but if the overflow pan is missing, or has cracked or developed a hole, or if the overflow pan’s drain line is plumbed to the same primary drain line that is clogged, water leakage will ensue. Property damage from unseen condensate leakage can be extensive and expensive by the time a leak is finally noted by occupants. Drain Trap A central air system routes condensation through a U-shaped trap located in the drain line just outside the air handler.

It's similar to the trap under your kitchen or bathroom sink; water in the trap prevents sewer gases originating where the condensate drain pipe terminates from infiltrating the air handler. In some conditions, such as during a long season of non-operation or when a gravity-fed drain line is not installed with the proper incline, the condensate drain trap may dry out and allow sewer gases to pass through the line. Unexplained noxious odors emitted from air conditioner supply vents in the home are the primary symptom of a dry condensate drain trap. Mold Growth Mold in the condensate drain system feeds off tiny airborne organic particulates sucked in through the return ducts and produces millions of mold spores. A mold colony is perfectly positioned to disperse spores into airflow in the supply ducts, and to infect the breathing air throughout your home. Allergic symptoms and other respiratory distress may result in susceptible individuals. In addition, mold growth originating in the condensate drain collector frequently expands into the evaporator coil, too, obstructing narrow air passages and strangling system airflow.