Why Your Air Conditioner Isn’t Getting Cold

“Why Isn’t My Air Conditioner Blowing Cold Air?”


This a common question that Phoenix homeowners tend to ask in summer: “Why is my air conditioner not cooling my home!?”


To help troubleshoot this irritating problem, we first need to ask some questions that will help pinpoint the main cause of the problem.


The first question is… “Is there air coming out of the supply vents, but it’s not cool?”


If there is no air at all coming out of your supply vents, go to the second question that follows. If you answered “yes” to the first question above, do the following steps:


1) Check your air conditioner’s thermostat fan setting— Maybe your air conditioner runs cold air at times but also hot/warm air at other times. In this case, make sure your AC’s fan it turned to an “auto” setting and not “on”. The “on” fan setting causes your AC to blow air even if it is hot/warm and not cooled down.


2) Check the AC’s air filter— Note that a dirty air filter  tends to block airflow to the AC’s air handler. Dirty air filters  cause the air coming out of the AC supply vents to be weak and also not very cold. Thus, always check your AC’s air filter to make sure it is not dirty. If necessary, change it.


3) Check the outside condition of your AC unit—Also make sure that the outside of your AC unit is not covered with dust, dirt, or even obstructed by grass, bush, or tree branch. If it is, then clean it or remove any obstructions. Give your AC’s outside unit some breathing room. If the outside fan is not working, commission a professional to fix it. Do these steps because otherwise, your AC’s outside unit will not be able to cool down refrigerant for it to blow cool air.


If none of the above helped in ensuring that your AC is blowing cool air, then it only means that your AC may already be low on its refrigerant. In case of a refrigerant leak, hire some professional help to find the leak then fix it.


The second question is… “Is your air conditioning unit not blowing any air at all?”


If no air at all is coming through the AC’s supply vents and the air conditioner isn’t working at all, do these following steps:


1) Check the AC’s air filter— If your AC’s air filters get too dirty, this will completely block airflow to the AC’s air handler and also freeze and damage the inside unit. Clean the air filter or if necessary, change it if it gets too dirty.


2) Check the thermostat temperature—Check that the temperature setting of the AC’s thermostat is 5 degrees (at least) below your room’s temperature.


3) Always set the thermostat to “cool”— This seems easy, but you may always have to check this setting every now and then because you never know if any one of your family members (or your pets) had accidentally set the thermostat to  “off” or even “heat” accidentally.


4) Make sure that electricity is going in to your AC unit—Check the service switches:


  • At the circuit breakers or fuses in the electrical panel.
  • By the compressor. (This is in the AC’s outside unit)
  • At the air handler. (This is in the AC’s inside unit or where your furnace typically is)
  • (NOTE: If any of the switches are turned “off”, then this may be the problem with your AC’s air functioning.)


Another example, an air conditioner that has a water sensor switch will automatically shut down if its condensate drain line is clogged and water is spilling in to an overflow pan. Simply put, your AC will shut down automatically in order to prevent water from damaging your home.


Also, if you air conditioner is not blowing (cold) air, then it may be overheating, or causing itself to pull in more electricity than normal, or more than the circuit breaker can handle. When this happens, the circuit breaker starts to cut power to your AC and if the circuit breaker keeps doing this even after your AC starts running for a little while, notice that something is really wrong. Don’t ignore overheating issues like this one.


If you’re in the Pheonix area, and in need of assistance, please call us at 602-790-5486

Handy man services. Not a licensed "contractor."