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EXCEL - IDEA: XBRL DOCUMENT - COMFORT SYSTEMS USA INCFinancial_Report.xls
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EX-32.2 - EX-32.2 - COMFORT SYSTEMS USA INCa2223211zex-32_2.htm
EX-32.1 - EX-32.1 - COMFORT SYSTEMS USA INCa2223211zex-32_1.htm
EX-23.1 - EX-23.1 - COMFORT SYSTEMS USA INCa2223211zex-23_1.htm
EX-31.1 - EX-31.1 - COMFORT SYSTEMS USA INCa2223211zex-31_1.htm
EX-31.2 - EX-31.2 - COMFORT SYSTEMS USA INCa2223211zex-31_2.htm
EX-10.33 - EX-10.33 - COMFORT SYSTEMS USA INCa2223211zex-10_33.htm

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EXHIBIT 21.1

SUBSIDIARIES OF COMFORT SYSTEMS USA, INC.

ENTITY NAME
  DOMESTIC
JURISDICTION
  FORMATION DATE  

ACI Mechanical, Inc. 

  Delaware     06/26/1998  

ARC Comfort Systems USA, Inc. 

  Delaware     03/17/1998  

Accu-Temp GP, Inc. 

  Delaware     05/21/1998  

Accu-Temp LP, Inc. 

  Delaware     05/20/1998  

Acorn Industrial, LLC

  North Carolina     01/03/1997  

Air Systems Engineering, Inc. 

  Washington     05/18/1973  

AirTemp, Inc. 

  Maine     10/15/1998  

Atlas-Accurate Holdings, L.L.C. 

  Delaware     12/28/1998  

Atlas Comfort Systems USA, Inc. 

  California     07/31/2007  

Atlas Comfort Systems USA, L.L.C. 

  Delaware     06/08/2007  

Batchelor's Mechanical Contractors, LLC

  Alabama     03/16/1981  

BCM Controls Corporation

  Massachusetts     10/03/1984  

California Comfort Systems USA, Inc. 

  California     05/18/1983  

ColonialWebb Contractors Company

  Virginia     03/30/1972  

Comfort Systems USA (Arkansas), Inc. 

  Delaware     03/17/1998  

Comfort Systems USA (Baltimore), LLC

  Delaware     10/15/1998  

Comfort Systems USA (Bristol), Inc. 

  Delaware     08/25/1997  

Comfort Systems USA (Carolinas), LLC

  North Carolina     01/01/2011  

Comfort Systems USA Energy Services, Inc. 

  Delaware     08/25/1997  

Comfort Systems USA G.P., Inc. 

  Delaware     08/12/1998  

Comfort Systems USA (Intermountain), Inc. 

  Utah     05/06/1969  

Comfort Systems USA (Kentucky), Inc. 

  Kentucky     02/10/1981  

Comfort Systems USA (MidAtlantic), LLC

  Virginia     01/01/2010  

Comfort Systems USA (Midwest), LLC

  Iowa     10/13/2009  

Comfort Systems USA National Accounts, LLC

  Indiana     07/28/1998  

Comfort Systems USA (Ohio), Inc. 

  Ohio     10/10/1979  

Comfort Systems USA (Pasadena), Inc. 

  Texas     06/28/2007  

Comfort Systems USA Puerto Rico, Inc. 

  Puerto Rico     08/09/1991  

Comfort Systems USA (South Central), Inc. 

  Texas     06/22/2007  

Comfort Systems USA (Southeast), Inc. 

  Delaware     03/24/1998  

Comfort Systems USA (Southwest), Inc. 

  Arizona     12/23/1977  

Comfort Systems USA (Syracuse), Inc. 

  New York     03/08/1965  

Comfort Systems USA (Texas), L.P. 

  Texas     08/14/1998  

Comfort Systems USA (Western Michigan), Inc. 

  Michigan     07/21/1989  

Control Concepts, LLC

  Georgia     12/16/1996  

Control Concepts Mechanical Services, LLC

  Georgia     01/17/2008  

CS53 Acquisition Corp. 

  Delaware     01/26/1999  

CSUSA (10), LLC

  North Carolina     10/21/2011  

Delcard Associates, LLC

  Delaware     06/23/2000  

Design Mechanical Incorporated

  Delaware     10/30/1997  

Dillingham & Smith Mechanical and Sheet Metal Contractors, LLC

  Tennessee     12/31/2003  

Dyna Ten Corporation

  Texas     06/26/1980  

Dyna Ten Maintenance Services, LLC

  Texas     08/07/2006  

Eastern Heating & Cooling, Inc. 

  New York     12/19/1988  

Eastern Refrigeration Co., Inc. 

  New York     01/30/1990  

Environmental Air Systems, LLC

  North Carolina     10/07/2011  

Envirotrol, LLC

  North Carolina     10/27/2011  

EnvirotrolSC, LLC

  South Carolina     01/29/2009  

ENTITY NAME
  DOMESTIC
JURISDICTION
  FORMATION DATE  

Granite State Holdings Company, Inc. 

  Delaware     11/02/2005  

Granite State Plumbing & Heating, LLC

  Delaware     07/31/2001  

H & M Mechanical, Inc. 

  Delaware     06/25/1998  

Helm Corporation

  Colorado     10/26/1972  

Hess Mechanical Corporation

  Delaware     03/17/1998  

Hudson River Heating and Cooling, Inc. 

  Delaware     08/19/2005  

H-VAC Supply, L.L.C. 

  Puerto Rico     10/18/2006  

Mechanical Technical Services, Inc. 

  Texas     06/22/2007  

Merit Mechanical, Inc. 

  Washington     02/14/1984  

MJ Mechanical Services, Inc. 

  Delaware     12/12/1997  

North American Mechanical, Inc. 

  Delaware     03/17/1998  

Plant Services Incorporated

  Iowa     07/02/1986  

Quality Air Heating and Cooling, Inc. 

  Michigan     09/10/1980  

Riddleberger Brothers, Inc. 

  Virginia     12/22/1958  

S.I. Goldman Company, Inc. 

  Florida     10/04/1976  

S.M. Lawrence Company, Inc. 

  Tennessee     03/08/1973  

SA Associates, Inc. 

  Utah     03/27/1984  

Salmon & Alder, L.L.C. 

  Utah     07/08/1996  

Seasonair, Inc. 

  Maryland     10/28/1966  

Temp-Right Service, Inc. 

  Delaware     09/25/1997  

The Capital Refrigeration Company

  Delaware     08/06/1998  



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SUBSIDIARIES OF COMFORT SYSTEMS USA, INC.