Evaporator Airflow Restriction

Evaporator airflow restriction failures are the boldest example in HVAC where skipping routine maintenance can result in repairs that cost many multiples of said maintenance. Evaporator airflow restrictions are nearly 100% avoidable. The #1 cause of evaporator airflow restrictions are dirty filters. Most return air filters will require replacement or cleaning every 90 days. The couple dollars in filter costs will not only save you from potential restriction failures but will save utility costs by helping your system to run more efficiently. Debris clogged in filters only causes your evaporator to work harder than it needs and may put undue stress on other components including your evaporator fan motor.

Evaporator airflow restrictions may also be caused by a dirty coil. It is recommended to have your coils cleaned annually to avoid this. Although a filter blocks the majority of debris, some will pass through. This debris has no where to go other than the coil. Algae and mold may also build on the coil preventing the proper airflow from passing over it.

Another cause of evaporator airflow restriction is improperly sized duct work. Duct work that is too small will cause airflow to become condensed and will create undue stress on the evaporator motor which will generally fail prematurely (within 1-2 year) in this case. 

If you have an evaporator airflow restriction your system may continue to operate fairly well until it rears its ugly head with an expensive repair. This may be a failed evaporator motor or a frozen evaporator coil. Although the coil may be thawed and the restriction cleared, cracks and leaks may easily occur in this process which results in a costly coil replacement.

The best way to safeguard yourself from evaporator airflow restrictions is to own an annual maintenance agreement that includes coil cleaning services and regularly replacing your filters. If you have repeated evaporator motor failures it is also advised to have your duct work inspected. If you suspect you have an evaporator airflow restriction Contact Melo Air today!

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Melo Air Inc

550 N Reo St Suite 300

Tampa, FL 33609

(813) 451-9438