Coil of Duty: Reading a Carrier® Chilled Water Coil model 28NC.

Carrier’s 28NC model chilled water coils are commonly found in Carrier 39N and 39T air handlers. Deciphering the model number is key to accurately specifying and ordering the correct coil. Let’s break down the code for the 28NC2022FGA207AL:

28NC-2-0-22-F-G-A-207-A-L

The "28NC" prefix identifies the coil as a chilled water model designed for cooling applications. It’s a good starting point when sourcing replacement coils.

28NC-2-0-22-F-G-A-207-A-L

The "2" following the model number indicates the coil's orientation—vertical placement without any special coatings. If the digit was replaced with a letter, it would suggest the presence of a protective coating like Heresite® or another similar finish.

28NC-2-0-22-F-G-A-207-A-L

This zero represents the number of rows in the coil. For Carrier chilled water coils, this value typically ranges from 4 to 10 rows. In this case, "0" corresponds to a 10-row configuration, which provides enhanced heat exchange efficiency.

28NC-2-0-22-F-G-A-207-A-L

The next two digits, "22," specify the number of tubes visible across the face of the coil. These tubes determine the finned height of the unit. Carrier generally uses ½-inch tubes, and the count can vary between 12 and 44 in increments of two. For this model, there are 22 tubes, meaning the finned height measures 27.5 inches. While most Carrier coils feature ½-inch tubes, it's always wise to verify the actual finned height during inspection.

28NC-2-0-22-F-G-A-207-A-L

The "F" denotes the circuiting configuration. It stands for "full circuit," meaning all 22 tubes feed into both the supply and return headers. Double-checking the coil's circuiting ensures proper functionality by confirming that all tubes connect seamlessly to the headers.

28NC-2-0-22-F-G-A-207-A-L

The "G" provides critical information about the coil's materials: fin type, casing material, and fin density. Copper fins paired with stainless steel casings and 8 fins per inch are indicated here. The "G" also implies that the coil does not require additional coatings like phenolic or epoxy, which are sometimes used for corrosion resistance. Always review the specific letter in this position, as each one carries unique implications depending on the coil’s application.

28NC-2-0-22-F-G-A-207-A-L

The "A" signifies the tube wall thickness, which in this case is .017 inches (or .016 inches for some variants). Standard copper walls are often sufficient, but thicker walls may be required under certain conditions to handle higher pressures.

28NC-2-0-22-F-G-A-207-A-L

The next set of digits, "207," represents the finned length of the coil in centimeters. Converting this to inches gives us 81.5 inches. This measurement is crucial for ensuring the coil fits within the available space in the air handler.

28NC-2-0-22-F-G-A-207-A-L

The "A" after the length indicates a steel male pipe thread (MPT) connection. Measuring the actual threads is advisable to confirm compatibility with existing piping systems.

28NC-2-0-22-F-G-A-207-A-L

Finally, the "L" specifies left-hand airflow. An "R" would indicate right-hand airflow instead. This detail is essential for aligning the coil correctly within the air handler.

With so many variables involved, Carrier chilled water coils offer a vast array of possibilities. If you encounter a model number you don't recognize or need assistance decoding, feel free to reach out to the experts at Nationwide Coils. We’re here to simplify your workflow and ensure your projects run smoothly.

Stay tuned for our next post where we’ll analyze a more widely used Carrier Chilled Water Coil model: 28CW1620DA1112---K.

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