EX-21.1 2 a2207539zex-21_1.htm EX-21.1
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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, Inc. 

  North Carolina   12/31/2009

Air Systems Engineering, Inc. 

  Washington   05/18/1973

AirTemp, Inc. 

  Delaware   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   06/29/2007

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

  Delaware   06/09/2006

Comfort Systems USA (CS1), Inc. 

  Delaware   12/14/2009

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   06/29/2007

Comfort Systems USA Puerto Rico, Inc. 

  Puerto Rico   05/31/1998

Comfort Systems USA (South Central), Inc. 

  Delaware   06/29/2007

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 (Twin Cities), Inc. 

  Minnesota   08/01/2001

Comfort Systems USA (Western Michigan), Inc. 

  Michigan   07/21/1989

CS53 Acquisition Corp. 

  Delaware   01/26/1999

Delcard Associates, LLC

  Delaware   06/23/2000

Delcard Mechanical, LLC

  New Jersey   11/07/2008

Design Mechanical Incorporated

  Delaware   10/30/1997

Dillingham & Smith Mechanical and Sheet Metal Contractors, LLC

  Tennessee   06/26/2008

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

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

ENTITY NAME
  DOMESTIC JURISDICTION   FORMATION DATE

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. 

  Delaware   06/29/2007

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. 

  Delaware   03/17/1998

S.M. Lawrence Company, Inc. 

  Tennessee   03/08/1973

SA Associates, Inc. 

  Utah   03/27/1984

Salmon & Alder, LLC

  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.