How to Read and Understand a Commercial HVAC Coil Schedule

Colby Maun • September 8, 2026

A coil schedule is a table included with mechanical drawings and specifications that summarizes the performance requirements and physical characteristics of the HVAC coils within the building. It comes with almost every type of coil and is an incredibly crucial piece within replacement projects. Understanding how to read it can drastically speed up your replacement process and reduce downtime in your next replacement project. Because of this importance, here is a comprehensive guide on how to read and understand a commercial HVAC coil schedule.

One of the most important parts of a coil schedule is the coil identification section. It acts as the starting point for identifying the specifics of the coil you’re replacing in a replacement job. This section gives information on the coil tag, equipment tag, location of the coil, type, and designation. The coil tag, especially, is key because it often provides you with the model and serial number. Each of these parts is essential information to identify the coil, and when given this information, HeatEX Technologies can often provide you with a quote without having to come out and measure the coil. This saves a ton of time on both ends when getting you your replacement coil.

Another important part of a coil schedule is the airflow information it contains. This tells you how much air is moving across the coil in a metric called CFM, which means cubic feet per minute. How much air flows across the coil is a huge performance metric and impacts heat-transfer capacity, face velocity, and pressure drop. In a replacement project, you want to make sure the replacement coil can handle the same airflow requirements as the previous coil.

A commercial HVAC coil schedule also includes information on entering and leaving air temperatures, as well as capacity for the coil. The entering and leaving air temperatures help calculate the capacity of the coil when combined with other factors. In addition, a comparison of the entering and leaving temperatures shows you what measure the coil needs to either heat or cool the air to while it passes through it. This matters because, in a replacement project, you need to know how hard your system will work to improve efficiency.

In a similar manner to entering and leaving air temperature, a coil schedule also contains information about the water flow and water temperatures inside the coil. This is extremely important for heat transfer efficiency, because the flow rate and water temperatures account for a large amount of the heat transfer process. Making sure you know what these metrics are in your coil will save you much time when making a replacement.

At HeatEX Technologies, we want to make sure that you are as prepared as possible for your next replacement project. We make sure to understand the precise specifications of your existing system before manufacturing a replacement coil, so that our replacement can be implemented as seamlessly as possible. For facility managers or mechanical contractors who prioritize low downtime in their projects, give HeatEX Technologies a call, and we will assist you with a speedy lead time and excellent customer service. We help with your project any way that we can, and we are always problem-solving new ways to assist you and your team.

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Common HVAC Coil Installation Mistakes and Their Effect on Your System

By Colby Maun • August 31, 2026

In a commercial HVAC coil replacement project, installation is a key factor that impacts both the performance and lifespan of the coil. A coil can be manufactured and selected perfectly for your replacement job, but if the installation is poor, your coil will experience lower performance and possibly a reduced lifespan. Because of this, making sure that installation goes as smoothly as possible is crucial for your system. To assist you with your next coil installation, here are some common commercial HVAC coil installation mistakes and how they affect your system in the long run. One of the most common mistakes that technicians can make in a coil replacement project is installing the coil in the wrong orientation. Coils are manufactured to operate in a particular orientation, and if they aren’t installed in that specific orientation, heat transfer efficiency and capacity are reduced. Installing a coil in the wrong orientation also affects airflow, since installing a coil in the wrong direction can force air in the wrong direction. Both of these complications negatively affect performance and lifespan in your system.

What is Circuiting and How Does it Effect a Coil?

By Colby Maun • August 24, 2026

In a commercial HVAC custom coil replacement job, circuiting is often undervalued, yet so crucial to effective operation in any coil. But what really is circuiting, and how does it affect your coil? Here is a breakdown of everything you need to know about circuiting for your next replacement job.

Why Coil Replacement Jobs Get Delayed, and How to Prevent Them

By Colby Maun • August 17, 2026

Delays in a commercial HVAC coil replacement project are one of the most frustrating things that a facility manager or contractor can face. A failed coil already creates problems such as comfort issues, downtime, and pressure from building owners, so making sure that your coil replacement project goes smoothly and without delay is crucial. To assist you with your next coil replacement job, here are some common causes of commercial HVAC coil replacement project delays and how you can prevent them in your job.

Chilled Water vs. Hot Water Coils: What's the Difference?

By Colby Maun • August 11, 2026

Commercial chilled-water and hot-water HVAC coils appear almost identical on the outside; however, they are more different than most people think. Both are water-based heat transfer components, but they work opposite each other and are better for different applications. Here is a full breakdown of the differences between chilled water vs hot-water coils, and how to decide which to use for your application.

Understanding Fan Coil Units

By Colby Maun • August 3, 2026

For buildings that require targeted zoning, such as hotels, offices, apartments, hospitals, retail spaces, and more, fan coils can assist in maintaining a comfortable indoor temperature. Each fan coil unit serves a particular space, which allows individual occupants to control their area of a building without affecting the rest of it. Understanding fan coils and how they work can help facility managers of these styles of buildings more properly maintain and replace units to prevent downtime in their systems. Here is a breakdown of how they work, the different types, and the common problems that they run into in their life cycle.

Which Material is Best for your Coil?

By Colby Maun • July 27, 2026

In commercial HVAC, one of the largest yet overlooked aspects of a custom coil replacement job is the materials that the coil is made of. Different materials thrive better in different systems and environments, which affects the lifespan and efficiency of the coil. Making sure that your replacement coil is best suited for your unique system and location is integral to any facility, and failure to do so can increase costs and decrease reliability. Here is a breakdown of each material in your coil and what scenarios to select each in.

What Actually Goes into Measuring a Coil

By Colby Maun • July 20, 2026

For any coil or heat exchanger replacement job, one of the first steps in the process is for HeatEX Technologies to measure the existing coil/heat exchanger to ensure a perfect fit in the unit. Recently, I had the privilege of going out to my second job site to take measurements with HeatEX Technologies. Here is my account of what actually goes into measuring a coil, and my experience from start to finish.

Trane CGAM070 Microchannel Conversion Case Study

July 13, 2026

After multiple refrigerant leaks sprang from a Trane CGAM070 air-cooled chiller in West Palm Beach, FL, our customer faced a difficult challenge. They had to decide whether to replace the failed microchannel condenser coils with new OEM microchannel coils or pivot and invest in a different, longer-term solution. After much evaluation, our customer decided to convert the chiller from aluminum microchannel coils to copper tube aluminum fin condenser coils.

The Biggest Takeaways from the 2026 ASHRAE Annual Conference for Commercial HVAC

By Colby Maun • July 6, 2026

Last week, from June 27 th to July 1 st , ASHRAE held its 2026 Annual Conference in Austin, TX, and brought together more than 2,233 HVAC professionals from all over the world. The conference covered a broad range of many topics prevalent in the industry today, from fundamentals and applications to AI in building design and construction. Here are some of the biggest takeaways from the 2026 ASHRAE Annual Conference for commercial HVAC.

5 Warning Signs Your Coil Needs Replacement

By Colby Maun • June 29, 2026

In a commercial HVAC unit, coil failure is one of the most frequent and costly problems a system can have. Coil failure in a commercial HVAC unit leads to performance, efficiency, and reliability issues, making it one of the most important aspects in the system. Coils can fail for many different reasons, and understanding when a coil is starting to need replacement can save facility managers tons of extra downtime and stress. Here are 5 warning signs that your commercial HVAC coil needs replacement, so that the next time your coil fails, you can be on top of the problem.

What Makes a Coil Custom?

By Colby Maun • June 22, 2026

What exactly makes a custom coil custom? Most facility managers assume that a custom coil only differs from OEM in sizing. The reality is that dimensions are only a fraction of what makes a custom coil custom. Each job is different, with many different factors going into a custom coil, such as dimensions, tube configuration, fin design, materials, and performance requirements. The most commonly thought of aspect when it comes to custom coils is the dimensions. This includes height, width, and depth of the coil, which allows for custom replacement coils to fit perfectly into the system they are designed for. Doing this without major modifications is crucial when manufacturing a custom replacement coil. The tube configuration of the coil also plays a very important role in customization. The circuitry, number of rows, and tube diameter all impact this aspect and contribute to the efficiency and heat transfer of a custom coil.

How Aging Infrastructure is Challenging Commercial Buildings

By Colby Maun • June 18, 2026

As a building gets older, it becomes much more likely to experience several different types of HVAC failure, which results in decreased efficiency and reliability in the system. Considering the fact that most commercial buildings in the US were built between 1970 and 2000, this aging infrastructure is becoming increasingly problematic in the world of HVAC. To increase difficulty, many organizations postponed renovation and retrofit projects during COVID and during times of economic uncertainty and inflation. Those decisions extended HVAC equipment beyond its initial design life in many cases, and now that it is finally time to renovate, there are significant challenges to doing so in those buildings. With today’s rising equipment costs, aging building stock, high energy costs, sustainability pressures, and limited budgets, many facility managers are burdened with attempting to keep their equipment running smoothly. As HVAC systems age, they experience coil degradation, efficiency losses, corrosion, and increased failures and downtime in general. Coils are usually one of the first parts to deteriorate, as they are exposed to plenty of different weathering aspects in the air, such as salt, moisture, and pollutants, to name a few. When a coil deteriorates, it reduces system capacity as a whole. Efficiency losses in older units are common as well, since with time, the unit has to work harder and harder to remain operating at the same capacity as it was when it was new. Reliability decreases for units due to increased unexpected failures and downtime, along with it becoming harder to source parts for repairs as technology advances and changes.