Top 5 Reasons Commercial HVAC Coils Prematurely Fail

Capital Coil & Air has come across virtually every scenario over the years in which a commercial HVAC coil had to be prematurely replaced, and we have since created an easy guide targeting the main reasons HVAC Coils prematurely fail.

  • Coil Plugging: If you are not changing filters and/or your commercial HVAC coils are not properly cleaned in a timely manner, your coil will actually begin to act as a filter. When dirt builds up on the coil, that blockage prevents heat transfer and can cause an approximate 20% to 40% drop in performance. Dirt adds to the coil resistance and can be a primary cause for your coil to fail prematurely.
  • Vibration: When your HVAC coils are installed near a moving piece of equipment, vibration can occur and cause leaks. You can tell if vibration is the main cause if leaks are near the tube sheet and look like they are slicing through the tube. If/when that happens, the coils should be isolated from the rest of the system to prevent vibration from causing damage. One way to combat this is by oversizing the tubesheet holes, but many manufacturers will not do this. Condenser Coils are usually the most common victims of vibration.
  • Corrosive Environment: This applies to both the air in the environment and inside the tubes. For instance, if there is a corrosive element in the air, it will eat away at the copper tubes; whether you have 0.020” wall or 0.049” wall. This is very common in coastal areas where there may be salt in the air. To keep the costs down from going to a stainless steel or cupro-nickel coil, we usually suggest coating the HVAC coils. Coatings are almost always within your budget, and its application will only add about a week to the overall 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 that 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 that 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.  ALSO be very careful when considering “freeze-proof” coils!  If you remove 5-6 inches from the fin length to make the “freeze-proof” application fit, your coil’s performance will suffer considerably. 
  • System Design: You would be amazed to learn how many HVAC coils were never designed properly for their systems. If there is a design problem, replacing the coil will only waste time and money; while you have done nothing other than duplicate the previous problem. A little known fact in the replacement market is that a high percentage of all our projects are because the coils were built incorrectly or were never designed correctly in the first place. In some cases, owners attempt to improve the coil’s performance by adding additional rows. Most however do this without taking into account the air pressure drop or fluid pressure drop that comes with it.

When dealing with an HVAC coil manufacturer, try to partner up with one who will walk you through the engineering and explain it along the way. Capital Coil & Air has well over a decade of experience and can help you diagnose whatever problem that you are experiencing correctly the first time. We look forward to working with you on your next project!

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Light-Duty Commercial Belt Drive Air Handler Units

There are lots of jobs that require large custom built Air Handler Units, as well as jobs that require Central Station Air Handler Units that are semi-custom built units. There are also plenty of jobs that Belt Driverequire neither of the above products. This application only requires that a light-duty standard unit be built that will match the duty and requirements of the job.

 Examples

  • Strip Malls/Shopping Centers
  • Dormitories and other college campus buildings
  • Military installations
  • Office areas in factories or other industrial settings
  • Condominiums

These examples do not need large heavy-duty units that are expensive and custom built. Instead, most of these units require standard light-duty construction that can provide 800-12,000 CFM. These units come with various options and choices, and are well-built with the highest quality components available. However, the units are not designed for overkill.

Capital Coil manufactures “Belt Drive” units that operate from 800 CFM (2 Tons) – 12,000 CFM (30 Tons). They are available in both horizontal and vertical airflow styles. Included are blowers, coils, drives, filters as well as additional accessories if required. Additionally, they are available in Chilled Water Coils, DX Coils, Hot Water Coils, and electric heat if needed.

So, why would you want to use these units in lieu of a heavy-duty air handler? Cost, cost, and cost again are the primary reasons. In addition, the light-duty units weigh less, they are more economical to install, and long-term maintenance is much easier. The overall cost of a Custom-Built Unit or a Semi-Custom Station Unit is dramatically higher and not needed in most installations. Please visit Capital Coil’s Belt Drive Product Page for additional descriptions of our units.

Shipping Schedules

  • Standard lead time: (6) weeks
  • (4) week quick-ship: 30% adder
  • (2) day quick-ship: 40% adder

Capital Coil is 100% transparent on all prices and pricing options. Each option is clearly listed on all quotes to help make your buying experience that much easier.

The Air Handler industry is pretty easy to understand when boiled down. If your job allows you to stay within “Production” type units that are built to normal standards without any customizations, you can save a lot on your price. The proper units for your project are still of the highest-grade quality, but they are much more of a fit for commercial, light-duty jobs.

Capital Coil & Air looks forward to working with you on all of your future Air Handler projects. You’ll be glad you did.

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