Air Conditioner That Doesn't Cool: 3 Signs That The Evaporator Is Failing

You turn on your air conditioning unit and notice that it simply doesn't provide any cooling effect anymore. While there are many different parts that may be the cause of this problem, there's a good chance that there is something wrong with the evaporator. The evaporator is responsible for removing heat from the air before it exits the air conditioning unit. Most of the time, a faulty evaporator is simply caused by dirt accumulating on its surface; however, if you've already cleaned the evaporator and still have no luck with getting cool air, here are 3 indicators that the evaporator is failing and needs to be replaced.

Warm Air Rather Than Cold Air

If your air conditioning unit is up and running perfectly with the only problem being that warm air is being emitted rather than cold air, then it's a good indicator that the only part that is malfunctioning is the evaporator. This is because all of the other parts in your air conditioning unit must be functioning for the air conditioner to still be releasing air into the room. The fact that the air is warm means that the evaporator is no longer able to absorb heat from the air anymore.

To confirm your theory, you can try measuring the temperature of the air before it enters the evaporator and after it exits. If there isn't any change or a big change, then you know that the evaporator needs to be replaced.

Water Leakages from the Evaporator

The evaporator could look completely fine, but still be failing. At times, you'll notice water leakages coming from a failing evaporator due to condensation buildup on its metal surfaces. Depending on how severe the problem is, the more condensation you'll see. This observation can be made without opening up the air conditioning unit. Simply look for water stains or the presence of water outside the air conditioning unit where the evaporator is.

You should also take this opportunity to see if any refrigerant is leaking out from the air conditioning unit. This may mean that the evaporator is not only malfunctioning, but that there is also a crack in the evaporator coils.

Frozen or Icy Copper Lines

Heat absorbed by the evaporator dissipates through copper lines to the outdoors. As a result, these copper lines are almost always warm or even hot when the air conditioning is turned on. If you want to double check to see whether the evaporator is failing or not, you should consider taking a look at the copper lines. If the copper lines are frozen or are cold, it means that the evaporator is no longer transferring heat from the air to the outdoors.

You should also check to see whether the copper lines are in good condition or not. If the copper lines are rusting or are showing signs of wear, it may also be a sign that the evaporator is not functioning properly and needs to be replaced.


The evaporators of your air conditioning unit may look like they're still in good condition, but they may actually be failing. If you believe that the evaporator is failing, you'll want to call an air conditioning contractor to perform the repairs and the inspection. Don't try to do it yourself because disassembling the evaporator from the air conditioning unit can be a lot of work. There are simply a lot of pieces and parts involved with this type of problem. In addition, there's also a chance that you can get electrocuted from the evaporator. In short, let a professional handle the job. For more information, check out websites like