We have many motor powered air handlers that are candidates for premium efficiency motors. Experience has shown that these new motors typically operate at a higher speed. What is the best way to determine the new sheve ratio to maintain the original fan speed. Trial and error using different sheve ratios is expensive in terms of labor and material. Thx

-- Terrence E. McMahon (Terrence.McMahon@yale.edu), March 20, 2002

Answers

You may contact the US Department of Energy OIT Clearinghouse to request a copy of an Excel spreadsheet that makes this calculation. The phone number is 1-800-862-2086. The spreadsheet has two parts. One part is to change the speed with an existing motor. The other part is to allow changing to a motor of a different speed without changing the speed of the fan.

-- Johnny Douglass (douglassj@energy.wsu.edu), March 27, 2002.