Troubleshooting AC Problems

Troubleshooting Tips from BrisbaneAirCondition

There are a few things you can check and correct yourself when your AC stops cooling that will save you a service call. First you need to determine a couple of things.  One, is the air handler working… Can you feel air blowing out of the vents? When I say air blowing it does not matter if it is cool air or room temperature.  If there is air moving the air handler is working. Now, one note about feeling air coming out of the vents.  Sometimes the evaporator coil, which looks a lot like the radiator on your car and located inside the air handling unit, will get a layer of ice on it and air can no longer move across it so it may seem like the air handler is not on.

The best way to verify if the unit is circulating air is to actually take a dollar bill and try to get it to stick to the return air grill… this is usually where you put your air filter. If it sucks the dollar bill to the grill then the air handler is running. Next, you need to see if the outdoor unit is running.  Check to see if the fan on top is spinning.

If it is, then look down hear the bottom of the unit where the two copper lines come out of your house.  one will be small and the other larger and usually covered in black insulation. Look right where that larger line comes into the unit and see if there is ice on it.  If there is then that means one of two things.  Either you are low on freon or you are not getting enough air across the evap coil in the air handler.  You need to check your air filter and if it is really dirty this could be the problem. Now, if you have ice, you need to turn the system off immediately.

Just go to the thermostat and put the heat cool switch in the off position and then turn the fan to the on position… it is usually in the auto position during normal operation. As the fan tries to pull air across the coil the ice will start to melt.  If your air handler is in the attic this increased melt off could overflow the drain pan if it is not draining properly so you need to try and locate a 3/4 inch white pvc line that comes out somewhere near the base of your house and make sure water is draining out of it.

Once you start getting good water flow give it a few hours to completely melt and if you had a dirty filter go ahead and change it and start up the system again and see if it cools the house properly.  Make sure you check every few hours for any ice buildup on the line outside… if you see any, shut the unit off and give me a call. Now, if you check the line and there is no ice, reach down and grab it with your hand.  if it is slightly cool to the touch then you are probably low on freon.  If this is the case give me a call for sure as I will save you an absolute fortune on a pond of freon!

If the line is not cool at all the compressor may not be running or you may be really low on freon. (yes, low freon can make the pipe freeze up or leave it the same temperature as the outside air… pretty weird, huh?) Once again, if this is the case, time to give me a call. Okay, if the inside unit is on but the outside is not, go ahead and check the breaker for the outdoor unit.  If it is off or tripped go ahead and reset it.  If it trips again then give me a call.

If it starts up fine then it may have tripped because the outdoor unit cycled on and off to quickly like during a brief power outage or when one of the kiddos turns the t-sat up and down real fast because they thought it might be a fun thing to do! If the breaker is not tripped then it is time to give me a call.

Next, if you did the air flow test and there is no air moving at all and you pay a gas or oil bill each month, then you might want to look for a red emergency switch on the wall in the hall or out in the garage near the access door to the house.  If you have a gas furnace acting as the air handler for the ac then you will have one of these switches. I get probably half a dozen of these calls each summer, especially when there are visitors in the home who blindly reach out into a dark garage or hallway and hit a switch trying to turn the lights on… of course they often turn off the emergency switch by mistake and don’t think to turn it back on because it is still dark and they cannot see that bright red cover!

Believe me, this happens all the time.  A lot of people troubleshooting achave no idea that the gas emergency switch shuts down everything, including the AC. Of course check your thermostat and make sure it is set right.  A lot of homes nowadays have programmable stats and sometimes the program gets messed up or if you just bought the house maybe the prior owner had it programmed to set back the cooling in the house while they are away at work.

Just go to the thermostat and press the down arrows until the reading is below the room temperature and then press “hold”. If the ac comes on and stays on until the house is nice and cool, the programs are probably the culprit… go online and look up your stat model and print out the programming instructions and set it as you desire.

Okay, that should give you a few things to look at before giving anyone a call. If you are still having trouble I’ll be glad to help you out. Just call 0415107129 today!