Item 5.02    Departure of Directors or Principal Officers; Election of Directors; Appointment of Principal Officers; Compensatory Arrangements of Certain Officers.

    (b) On October 22, 2009, Comfort Systems USA, Inc. (the “Company”) determined that Thomas N. Tanner, Executive Vice President — Mergers and Acquisitions, will transition from his position as an Executive Vice President of the Company effective November 1, 2009 and will no longer be an executive officer of the Company.  The Company expects Mr. Tanner to continue with the Company, and has offered Mr. Tanner the position of Senior Regional Vice President in charge of the Company’s eastern region.

 SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

  Comfort Systems USA, Inc.  
       
Date:  October 22, 2009
By:
/s/ Trent T. McKenna  
    Trent T. McKenna  
   
Vice President and General Counsel