Coil Plugging: If filters are not changed or your HVAC coils cleaned properly in a timely manner, your coil will actually act as a filter. When dirt builds up on the coil, it will prevent heat transfer and can cause a 20% to 40% drop in performance. Dirt adds to the coil resistance and will absolutely cause your coil to fail prematurely.
Corrosive Environment: This applies to both the air in the environment and inside the tubes. For instance, if there is something in the air that is corrosive, it will eat away at the copper tubes whether you have thick wall. This is very common in saline climate conditions. To keep the costs down from going to a stainless steel or cupro-nickel coil, HVAC coils will be coated. Coatings are almost always within the budget and only add about a week to the lead time. Steam condensate and untreated water can cause corrosion within the tubes of HVAC coils as well. If you have a steam coil that has failed before the one year warranty, there’s a great chance corrosive agents are in the steam and it’s eating away at the copper tubes.
Freeze-Ups: Most people think that when HVAC coils freeze, the water or condensate laying in the coil freezes into ice and it expands causing the tubes to bulge and eventually spring leaks. What really happens is the coil will freeze in multiple areas simultaneously and it’s the pressure between these areas that cause the tubes to swell and eventually burst. These are very easy to spot as the leaks will run the length of the tube rather than around the tube. And be very careful when considering “freeze proof” coils. If you remove 5-6 inches from the fin length to make it fit, the coil performance will suffer considerably.
System Design: You would be amazed how many HVAC coils were never properly designed for their systems. If there was a problem with design, replacing the coil will only duplicate the problem. A high percentage of all our projects were because the HVAC coils were built incorrectly or was never designed right in the first place. Sometimes, owners want to improve performance by adding a couple rows, but don’t consider the air pressure drop or fluid pressure drop that comes with it.
So, you should take care of your HVAC coils to provide comfortable, hygienic and energy efficient environments.