Category Archives: How To’s

Coil Measuring Basics

Here is a short guide on the basics of measuring a coil for replacement.


This is broken down in to four simple stages: Tubes, Fins, Casing, and Connection.


  • The first step is to determine the outside diameter of the tubes i.e. 3/8″, 1/2″, 5/8″.
    • This can be done by using a caliper or a tape measure.
  • Next we need to determine how many rows deep the coil is.
    • This is determined by counting the number of rows of tubes through the depth of the coil.
    • The example below would be three rows deep.



  • To determine the face area of the coil we need to measure the height and length of the fin pack. This measurement should be taken on the inside of the casing flanges.
  • Next we need to measure the number of fins per inch. This can be done by laying a tape measure horizontally against the face of the fins and counting the number of fins within one inch.



  • Measure the height, length, and depth of all casing.
    • Make sure to measure the top/bottom and side flanges.







  • The next step is to measure the outside diameter of any headers and connections and their locations.
    • Measure the top connection from the top of the coil to the tube center of the connection tube.
    • Measure the bottom connection from the bottom of the coil to the tube center of the connection tube.


  • Finally we want to measure how far the headers and connections extend out from the face of the coil.


connection 1

We hope this short guide to coil measuring basics helps with your next coil measurement. We recommend using one of our blank coil drawings to keep track of all of your measurements. They can be found on each of our coil pages. If you have any questions or would like additional help please call one of our team members at 866-320-9050.