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                                                                    EXHIBIT 10.1


                              EMPLOYMENT AGREEMENT


         THIS EMPLOYMENT AGREEMENT (this "Agreement") between COMFORT SYSTEMS
USA (TEXAS), L.P., a Texas limited partnership (the "Company"), and Gary E. Hess
("Employee") is entered into effective as of the 1st day of April, 2002.

                                    RECITALS

         1.       The Company, Comfort Systems USA, Inc., a Delaware
                  corporation, and its subsidiaries and affiliates
                  (collectively, the "Comfort Group") are engaged in the
                  business of mechanical contracting services, including
                  heating, ventilation and air conditioning, piping, plumbing
                  and electrical and related services ("Services").

         2.       Employee has been employed by the Company in various executive
                  positions through March 31, 2002, most recently as its Chief
                  Operating Officer and President. In connection with the
                  transition of Employee from such position to a new part time
                  role, the Company desires to engage Employee in a part-time
                  capacity to facilitate the transition with respect to various
                  matters with which Employee has been involved and the Company
                  also desires to use Employee as a resource during the term of
                  this Agreement.

         3.       Employee is a party to that certain Employment Agreement dated
                  January 1, 2001 between the Employee and the Company (the
                  "Prior Employment Agreement").

         NOW, THEREFORE, in consideration of such engagement and of the
promises, terms, covenants and conditions set forth herein, the Company and
Employee hereby agree as follows:

1.       PRIOR EMPLOYMENT AGREEMENT TERMINATED. Employee hereby agrees that the
         Prior Employment Agreement is hereby irrevocably terminated. As
         consideration for such termination and in complete satisfaction and
         release of all rights and benefits of the Employee under the Prior
         Employment Agreement, Company will pay to Employee a lump-sum payment
         equal to $250,000. The payment will be made on or before April 15, 2002
         and shall be subject to all legally required withholding.

2.       ENGAGEMENT AND DUTIES. The Company hereby engages Employee as a
         part-time Employee for a period commencing on the date hereof, and
         ending on September 30, 2005 (the "Term"), to perform such duties as
         the Company may reasonably specify. Employee hereby accepts this
         engagement and agrees to perform and make himself available from time
         to time to and to devote reasonable time, attention and efforts, but
         not to an average of 90 hours per quarter, to promote and further the
         Company's business as the Company may reasonably require.

3.       COMPENSATION, EXPENSES AND TERMINATION. During the term of Employee's
         engagement with the Company, for all services rendered by Employee to
         the Company, the Company shall pay to Employee $10,715 per calendar
         quarter for each of the fourteen



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         quarters during the Term, for an aggregate total payment of $150,010.
         Payments will made pursuant to the Company's normal pay practices,
         including all required deductions. Employee agrees that as a result of
         his part-time status he will not be entitled to participate in any of
         the Company's welfare benefit programs, including and health and dental
         insurance. If at any time during the Term (i) substantially all of the
         outstanding capital stock or assets of the Comfort Group is acquired,
         by merger or otherwise, or (ii) the Employee is terminated without
         cause, then, within 30 days of such event the Company shall pay to
         Employee a single lump sum payment equal to all of the remaining salary
         payable under this Agreement and shall vest any options that he holds
         that are not vested and that have not otherwise been exercised or
         terminated, provided, however, in the event Employee has accepted
         full-time employment with any third party or has associated himself in
         any capacity with a third party engaged in providing Services, the
         Company may terminate this Agreement without vesting any options or
         paying the remaining salary otherwise payable hereunder.

4.       CONFIDENTIALITY.

         a.       As used herein, the term "Confidential Information" means any
                  information, technical data or know-how of the Company and the
                  other members of the Comfort Group, whether acquired during
                  the Term or prior to the Term in Employee's former capacity,
                  including, but not limited to, that which relates to
                  customers, business affairs, business plans, financial
                  matters, financial plans and projections, pending and proposed
                  acquisitions, operational and hiring matters, contracts and
                  agreements, marketing, sales and pricing, prospects of the
                  Comfort Group, and any information, technical data or know-how
                  that contain or reflect any of the foregoing, whether prepared
                  by the Company, any other member of the Comfort Group,
                  Employee or by any other person or entity; provided, however,
                  that the term "Confidential Information" shall not include
                  information, technical data or know-how that Employee can
                  demonstrate is generally available to the public not as a
                  result of any breach of this Agreement by Employee.

         b.       Except in the performance of Employee's duties as a Employee
                  to the Company, Employee will not, during or after the term of
                  Employee's engagement with the Company, disclose to any person
                  or entity or use, for any reason whatsoever, any Confidential
                  Information.

5.       NON-COMPETITION.

         a.       Employee will not, during the Term and for a period of one
                  year following the Term, for any reason whatsoever, directly
                  or indirectly, on Employee's behalf or on behalf of or in
                  conjunction with any other person, company, partnership or
                  business of whatever nature:

                  (i)      engage within one hundred miles of where the Comfort
                           Group conducts business (the "Territory") in any
                           capacity whatsoever for any business or person
                           engaged in Services;



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                  (ii)     call upon any person who is an employee of the
                           Company or any other member of the Comfort Group for
                           the purpose of enticing such employee away from or
                           out of the employ of the Company or the Comfort
                           Group;

                  (iii)    call upon any person which is, at that time, or which
                           has been, within the term of such Employee's
                           engagement, a customer of the Company or any other
                           member of the Comfort Group for the purpose of
                           selling Services; or

                  (iv)     call upon any prospective acquisition candidate, on
                           Employee's own behalf or on behalf of any competitor,
                           which candidate was called upon by Employee on behalf
                           of the Company or any other member of the Comfort
                           Group or for which an acquisition analysis was made
                           by Employee on behalf of the Company or any other
                           member of the Comfort Group for the purpose of
                           acquiring such entity.

         b.       It is agreed that the period during which this Section 4 shall
                  be effective shall be computed by excluding from such
                  computation of time any time during which Employee is in
                  violation of this Agreement.

6.       RETURN OF COMPANY PROPERTY. All records, plans, manuals, "field
         guides", memoranda, lists, documents, statements and other property
         delivered to Employee by or on behalf of the Company or any other
         member of the Comfort Group, by any customer of the Company or any
         other member of the Comfort Group (including but not limited to, any
         such customers obtained by Employee), by any acquisition candidate of
         the Company or any other member of the Comfort Group, and all records
         compiled by Employee which pertain to the business or activities of the
         Company or any other member of the Comfort Group, whether acquired
         during the Term or before the Term in Employee's prior capacity, shall
         be and remain the property of the Company, and be subject at all times
         to its discretion and control.

7.       SEVERABILITY. The covenants set forth in this Agreement are severable
         and separate, and the unenforceability of any specific covenant shall
         not affect any other covenant or provision set forth herein. In the
         event that any court of competent jurisdiction shall determine that any
         covenant contained herein is unreasonable, it is the intention of the
         parties that such restrictions be enforced to the fullest extent that
         the court deems reasonable, and this Agreement shall thereby be
         reformed.

8.       SURVIVAL. The provisions and covenants of Sections 3, 4, 5, 6 and 7
         shall survive termination of this Agreement.

9.       SPECIFIC PERFORMANCE. Because of the difficulty of measuring economic
         losses to the Company as a result of a breach of the covenants
         contained in Sections 3, 4 and 5 and because of the immediate and
         irreparable damage that could be caused to the Company for which it
         would have no other adequate remedy, Employee agrees that the Company
         shall be entitled to specific performance and that such covenants may
         be enforced by the Company in the event of any breach or threatened
         breach by Employee, by injunctions, restraining orders and other
         appropriate equitable relief. Employee further agrees to waive any
         requirement for the securing or posting of any bond.


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10.      GOVERNING LAW. This Agreement shall be governed by and construed in
         accordance with the internal laws of the State of Texas.

         IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the day and year first above written.

EMPLOYEE:                               COMPANY:

                                        COMFORT SYSTEMS USA (TEXAS), L.P.
                                        By: Comfort Systems USA G.P., Inc.


/s/ Gary E. Hess
---------------------------
Gary E. Hess                            By: /s/ William George
                                           -------------------------------------
                                                   William George
                                                   Senior Vice President



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