How Do I Check for a Dirty Evaporator Coil?

how to check ac coils

How Do I Check for a Dirty Evaporator Coil?

Posted by
Ed Miller on Thu, May 16, 2013

Almost all air conditioning units have an evaporator coil that serves the purpose of removing heat from the air that passes through the filters of the units and making the coolant liquid in the evaporator coils absorb the heat, thereby cooling the air. This is part of the fundamental working principle of any a/c system and thus it should be obvious that anything that causes the evaporator to malfunction would vastly hinder the proper operation of the device. The best way to deal with the issue is to contact a professional air conditioning and heating company like Snyder AC, Jacksonville, FL.

A dirty evaporator coil is not a simple thing to identify and tackle. This is because the evaporator is not a part that is open or easy to access – it is usually found deep within the bowels of the casing of the air conditioner unit. At the least, a few screws and maybe some plastic or metal casings will have to be removed to be able to reach the evaporator easily. It would be prudent to check the user or service manual of your product to correctly identify where the evaporator is and how to access it easily. Once the evaporator coil is identified and located, it is still not easy to identify if a dirty coil is the cause of the problem.

Check Air Pressure

One of the most commonly used methods to see if a dirty evaporator coil is causing a loss in performance is to check the air pressure at both the entry to the air vents that takes in room temperature air and also the pressure at the output of the air conditioning unit. Then compare the pressure difference between the two values to what it says in the instruction manual. If the values are off by a lot, then it is likely that the evaporator coils need cleaning.

Gauging Temperature

Another way to check for dirty evaporator coils is to gauge the temperature gradient in the air before and after exposure to the evaporator coils. A normal range of the drop in temperatures achieved should be close to 20 to 25 degrees Fahrenheit. If the values are below this range then it is a sure sign that build up sediments in the evaporator coils are affecting the system efficiency.

Checking the amount of current flowing through the leads of the supply fan of the evaporator is another identification method used by a lot of professional servicemen of air conditioning systems. A dirty and clogged coil will not allow the supply fan to keep the coolant moving at high volumes, thus due to a phenomenon called dynamic braking, the speed of the supply fan is reduced which in turn reduces the amperage of the fan terminals. There are specific tools designed for the purpose of checking the current levels in the supply fan, or one could alternatively use a standard multimeter while taking care to place the leads at the correct positions.

Once you identify with certainty that the evaporator coils are in need of a good cleaning, then it is best to contact a trustworthy and professional air conditioning and heating company who do repair work as well as installations. This will make sure that they have the prerequisite skills and experience to carry out a task like cleaning out the evaporator coils and changing the liquid coolant if required. This is not a simple task that can be carried out by laymen since coolants are usually poisonous or at the least partially toxic to humans as well as the environment and so contact your a/c service company in Jacksonville, FL to do a professional job for you.

Snyder A/C has the best professionals for the job. Founded in 1973, we have been serving the residents in Northern Florida for forty years, and our loyal clientele proves the dedication and standards of our work and our commitment to our customers to provide the best possible job.

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