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

The 28CW chilled water coil is commonly found in Carrier air handlers like the 39EB and 39ED models. The model number is a code that gives you all the details you need to quote or replace the coil. Let’s go through it step by step:

28CW-1-6-20-D-A-1-112---K

28CW – This is the base model for a chilled water coil.

1 – Indicates a steel connection. A "2" would mean brass, which is less common.

6 – Refers to the number of rows in the coil. Common options are 4, 6, 8, or 10 rows.

20 – Shows the number of tubes in the face of the coil. For Carrier coils, this typically corresponds to the finned height. A 20-tube coil usually means a 25-inch finned height (using ½" tubes).

D – Stands for “double” circuiting. This means the coil has double the number of tubes compared to the standard configuration. You should check that there are 40 tubes feeding into the supply and return headers.

A – Indicates the type of fins and casing. "A" means aluminum fins at 8 fins per inch. Other options include B (aluminum, 14 FPI), K (copper, 8 FPI), and L (copper, 14 FPI).

1 – Specifies the tube wall thickness. A "1" means a .016-inch copper tube wall, while a "2" would indicate a thicker wall.

112 – Represents the finned length of the coil in inches. In this case, it's 112 inches. Be sure to confirm if it's in centimeters or inches, as conversion may be needed.

K – This one is a bit of a mystery. No one really knows what the "K" stands for—Kite? Knish? Kazoo? It could be anything, so always double-check your measurements on site.

There are countless combinations when it comes to Carrier chilled water coils. If you're ever unsure about a model number or need help decoding it, don't hesitate to reach out to the experts. At Nationwide Coils, our HVAC professionals have nearly two decades of experience and are here to help make your job easier.

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