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EX-31.1 - EX-31.1 - COMFORT SYSTEMS USA INCa2227387zex-31_1.htm
EX-10.40 - EX-10.40 - COMFORT SYSTEMS USA INCa2227387zex-10_40.htm
EX-32.1 - EX-32.1 - COMFORT SYSTEMS USA INCa2227387zex-32_1.htm
EX-32.2 - EX-32.2 - COMFORT SYSTEMS USA INCa2227387zex-32_2.htm
EX-23.1 - EX-23.1 - COMFORT SYSTEMS USA INCa2227387zex-23_1.htm
EX-31.2 - EX-31.2 - COMFORT SYSTEMS USA INCa2227387zex-31_2.htm
10-K - 10-K - COMFORT SYSTEMS USA INCa2227387z10-k.htm

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EXHIBIT 21.1

SUBSIDIARIES OF COMFORT SYSTEMS USA, INC.
as of December 31, 2015

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, 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 Energy Services, Inc.    Delaware   08/25/1997
Comfort Systems USA G.P., Inc.    Delaware   08/12/1998
Comfort Systems USA (Indiana), LLC   Indiana   06/08/2015
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 (Ohio), Inc.    Ohio   10/10/1979
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 Strategic Accounts, LLC   Indiana   07/28/1998
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
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
Granite State Holdings Company, Inc.    Delaware   11/02/2005
Granite State Plumbing & Heating, LLC   Delaware   07/31/2001
H & M Mechanical, Inc.    Alabama   08/06/1998
Helm Corporation   Colorado   10/26/1972

ENTITY NAME
  DOMESTIC
JURISDICTION
  FORMATION
DATE
Hess Mechanical, LLC   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



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SUBSIDIARIES OF COMFORT SYSTEMS USA, INC. as of December 31, 2015