EX-21.1 2 a2213101zex-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, 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 |
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 |
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 |
Helm Corporation |  | Colorado |  |  | 10/26/1972 |

ENTITY NAME |  | DOMESTIC JURISDICTION |  | FORMATION DATE |
--- | --- | --- | --- | --- | ---
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, 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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EXHIBIT 21.1

SUBSIDIARIES OF COMFORT SYSTEMS USA, INC.