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                                                                    EXHIBIT 10.1


                              EMPLOYMENT AGREEMENT


         THIS EMPLOYMENT AGREEMENT (this "Agreement") between Eastern Heating &
Cooling, Inc. (the "Company"), and Fred Giardenelli, Jr. ("Executive") is
entered into and effective as of the 1st day of June, 2003. This Agreement
supersedes any other employment agreements or understandings, written or oral,
between the Company and Executive.

                                 R E C I T A L S

         The following statements are true and correct:

                  As of the date of this Agreement, the Company, and its
         affiliates (collectively, the "Comfort Group") are engaged in the
         business of mechanical contracting services, including heating,
         ventilation and air conditioning, plumbing, fire protection, piping and
         electrical and related services ("Services").

                  Executive is employed by the Company in a confidential
         relationship wherein Executive, in the course of Executive's employment
         with the Company, will become familiar with and aware of information as
         to the Comfort Group's customers, specific manner of doing business,
         including the processes, techniques and trade secrets utilized by the
         Comfort Group, employees and future plans with respect thereto, all of
         which has been and will be established and maintained at great expense
         the Comfort Group. This information is a trade secret and constitutes
         the valuable goodwill of the Company and the Comfort Group.

                  Each of Company and Executive desire to establish Executive's
         employment by the Company pursuant to this Agreement.

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

                               A G R E E M E N T S

         1.       Employment and Duties.

                  (a) The Company hereby employs Executive in an executive
         position and Executive hereby accepts this employment upon the terms
         and conditions herein contained. Executive agrees to devote
         substantially all of Executive's business time, attention and efforts
         to promote and further the business of the Company.

                  (b) Executive shall faithfully adhere to, execute and fulfill
         all lawful policies established by the Company and the Comfort Group,
         including the Comfort Systems USA ("Comfort") Corporate Compliance
         Policy.

                  (c) Executive shall not, during the term of Executive's
         employment hereunder, be engaged in any other business activity pursued
         for gain, profit or other pecuniary advantage if such activity
         interferes in any material respect with Executive's duties and
         responsibilities hereunder. The foregoing limitations shall not be
         construed as prohibiting


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         Executive from making personal investments in such form or manner as
         will neither require Executive's services in the operation or affairs
         of the companies or enterprises in which such investments are made nor
         violate the terms of Section 4.

         2. Compensation. For all services rendered by Executive, the Company
shall compensate Executive as follows:

                  (a) Base Salary. Effective the date hereof, the base salary
         payable to Executive is $180,000 per year, payable on a regular basis
         in accordance with the Company's standard payroll procedures, but not
         less often than monthly. On at least an annual basis, the Company will
         review Executive's performance and may make adjustments to such base
         salary if, in its discretion, any such adjustment is warranted.

                  (b) Executive Perquisites, Benefits and Other Compensation.
         Executive shall be entitled to receive additional benefits and
         compensation from the Company in such form and to the extent specified
         below:

                           (i) Coverage, subject to contributions required of
                  employees generally, for Executive and Executive's dependent
                  family members under health, hospitalization, disability,
                  dental, life and other insurance plans that the Company may
                  have in effect from time to time for the benefit of its
                  employees.

                           (ii) Reimbursement for all business travel and other
                  out-of-pocket expenses reasonably incurred by Executive in the
                  performance of Executive's services pursuant to this
                  Agreement. Reimbursable expenses shall be appropriately
                  documented in reasonable detail by Executive, and shall be in
                  a format consistent with the Company's expense reporting
                  policy.

         3.       Confidentiality.

                  (a) Confidential Information. 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,
         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, Executive or any
         other person or entity; provided, however, that the term "Confidential
         Information" shall not include information, technical data or know-how
         that Executive can demonstrate is generally available to the public not
         as a result of any breach of this Agreement by Executive.

                  (b) No Disclosure. Except in the performance of Executive's
         duties as an executive of the Company, Executive will not, during or
         after the term of Executive's engagement with the Company, disclose to
         any person or entity or use, for any reason whatsoever, any
         Confidential Information.


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         4. Non-Competition Agreement.

                  (a) Competition. Executive will not, during the period of
         Executive's employment by or with the Company, and for a period of one
         year immediately following the termination of Executive's employment,
         for any reason whatsoever, directly or indirectly, on behalf of
         Executive or on behalf of or in conjunction with any other person,
         company, partnership, corporation or business of whatever nature:

                           (i) engage, as an officer, director, shareholder,
                  owner, partner, joint venturer, or in a managerial capacity,
                  whether as an employee, independent contractor, consultant or
                  advisor, or as a sales representative, or make or guarantee
                  loans or invest, in or for any business engaged in Services in
                  competition with the Company Group or any other member of the
                  Comfort Group within seventy-five (75) miles of where any
                  Comfort Group operation or subsidiary conducts business if
                  within the preceding two years Executive has had
                  responsibility for, or material input or participation in, the
                  management or operation of such other operation or subsidiary
                  (the "Territory");

                           (ii) call upon any person who is, at that time, an
                  employee of the Company or any other member of the Comfort
                  Group in a technical, managerial or sales capacity for the
                  purpose or with the intent of enticing such employee away from
                  or out of the employ of the Company or such other member of
                  the Comfort Group;

                           (iii) call upon any person or entity which is at that
                  time, or which has been within ONE (1) years prior to that
                  time, a customer of the Company or any other member of the
                  Comfort Group for the purpose of soliciting or selling
                  Services;

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

         Notwithstanding the above, the foregoing covenants shall not be deemed
         to prohibit Executive from acquiring as an investment not more than one
         percent (1%) of the capital stock of a competing business whose stock
         is traded on a national securities exchange or on an over-the-counter
         or similar market.

                  (b) No Violation. It is specifically agreed that the period
         during which the agreements and covenants of Executive made in this
         Section 4 shall be effective shall be computed by excluding from such
         computation any time during which Executive is in violation of any
         provision of this Section 4.

                  (c) Extension. Notwithstanding the foregoing provisions of
         this paragraph 4, if this Agreement is terminated pursuant to paragraph
         5, then, upon written notice to


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         Executive not later than 60 days following the date of such
         termination, the Company may at its option extend by up to twelve
         additional months the agreements and covenants contained in this
         paragraph 4 by paying to Executive a number of months of base salary
         equal to the length of the extension specified in such notice, any such
         amounts to be payable during such extension period in a manner
         consistent with the Company's standard pay practices.


         5. Term; Termination; Rights on Termination. The term of this Agreement
shall begin on the date hereof and continue for a term of two (2) years, unless
renewed or terminated under this Paragraph 5. At the end of the initial term
described in the preceding sentence, this Agreement shall automatically renew
for succeeding terms of one (1) year each (subject to termination under this
Paragraph), unless either party shall, at least 10 days prior to the expiration
of any term, give written notice of an intention not to renew this Agreement.
This Agreement and Executive's employment may be terminated in any one of the
following ways:

                  (a) Death. The death of Executive shall immediately terminate
         this Agreement with no severance compensation due to Executive's
         estate.

                  (b) Disability. If, as a result of incapacity due to physical
         or mental illness or injury, Executive shall have been absent from
         Executive's full-time duties hereunder for four (4) consecutive months,
         then thirty (30) days after receiving written notice (which notice may
         occur before or after the end of such four (4) month period, but which
         shall not be effective earlier than the last day of such four (4) month
         period), the Company may terminate Executive's employment hereunder,
         provided Executive is unable to resume Executive's full-time duties at
         the conclusion of such notice period. In the event this Agreement is
         terminated as a result of Executive's disability, Executive shall
         receive from the Company Executive's base salary at the rate then in
         effect for six (6) months, and such amount shall be payable during such
         period in a manner consistent with Company's standard pay practices.
         The amount payable hereunder shall be decreased by the amount of
         benefits otherwise actually paid by the Company to Executive or on
         Executive's behalf or under any insurance procured by the Company.

                  (c) Good Cause. The Company may terminate this Agreement ten
         (10) days after written notice to Executive for good cause, which shall
         include any of the following: (i) Executive's willful or material
         breach of this Agreement; (ii) Executive's failure to perform any of
         his material duties following notice by the Company to Executive of
         such improper performance and Executive's failure to correct the
         improper performance to the satisfaction of the Company within a
         reasonable time; (iii) Executive's gross negligence in the performance
         or intentional nonperformance of any of Executive's material duties and
         responsibilities hereunder; (iv) Executive's willful dishonesty, fraud
         or misconduct with respect to the business or affairs of the Company or
         any other member of the Comfort Group; (v) Executive's conviction of a
         felony crime; (vi) Executive's confirmed positive illegal drug test
         result; (vii) sexual harassment by Executive; or (viii) willful or
         material failure by Executive to comply with Comfort's Corporate
         Compliance Policy or other Company policies. In the event of a
         termination for good cause, as enumerated above, Executive shall have
         no right to any severance compensation.


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                  (d) Without Cause. At any time after the commencement of
         Executive's employment, Executive or the Company may, without cause,
         terminate this Agreement and Executive's employment, effective fifteen
         (15) days after receipt of written notice. Should Executive be
         terminated by the Company without cause, Executive shall receive from
         the Company Executive's base salary at the rate then in effect for one
         year, and such amount shall be payable during such period in a manner
         consistent with the Company's standard pay practices. If Executive
         resigns or otherwise terminates Executive's employment, Executive shall
         receive no severance compensation.

                  (e) Change of Control, Change of Duties, Change of
         Compensation or Change of Location.

                           (i) At any time during the SIX-MONTH period following
                  a change of control of Comfort Systems USA, Inc. and/or
                  Eastern Heating and Cooling, Inc., a change of duties of
                  Executive, a change of compensation of Executive or a change
                  of location of Executive (collectively "Change Events"),
                  Executive may elect by written notice to receive a lump-sum
                  payment equal to his annual base salary as of the date of such
                  Change Event, provided, however, if Executive receives such
                  Change Event payment, then for the remaining term of this
                  Agreement he shall not be entitled to receive separation
                  payments as otherwise provided under this Section 5.
                  Notwithstanding the preceding sentence, in the event that in
                  connection with a change of control of Comfort Systems USA,
                  Inc., any former owners of the twelve original founding
                  companies of Comfort Systems USA, Inc. receives a change of
                  control payment under his Employment Agreement dated July 2,
                  1997 that is more than his annual base salary, Executive may
                  instead elect to resign and receive the same multiple of his
                  base salary as such other founding company owner has received,
                  and such payment, if elected by Executive, shall be in lieu
                  of, and in cancellation of, all of Executive rights under this
                  and any preceding Employment Agreement.

                           (ii) For purposes of subparagraph (e)(i), the term
                  "change of control" shall include with respect to Comfort
                  Systems USA, Inc. and/or Eastern Heating and Cooling, Inc. a
                  sale of a majority of either corporation's capital stock, a
                  sale of substantially all of either corporation's assets, a
                  merger pursuant to which the ultimate shareholders of either
                  corporation do not hold a majority of voting interest
                  subsequent to said merger, or any other transaction of similar
                  effect.

                           (iii) For purposes of subparagraph (e)(i), the term
                  "change of duties" with respect to Executive shall include any
                  permanent and material adverse change, other than by the
                  Executive himself, in the nature or scope of Executive's
                  responsibilities and authorities from such responsibilities
                  and authorities immediately prior to such change of duty.

                           (iv) For purposes of subparagraph (e)(i), the term
                  "change of compensation" of Executive shall include a decrease
                  in the annual base salary in effect as of the date of the
                  change of compensation payable by the Company thereof to
                  Executive, other than as a result of the comparable change in
                  compensation payable to substantially all other executive
                  officers of the Company on the basis of the Company's or any
                  subsidiary's financial performance.


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                           (v) For purposes of subparagraph (e)(i), the term
                  "change of location" of Executive shall include a relocation,
                  other than by the Executive himself, of more than 25 miles
                  from Executive's work location immediately prior to the change
                  of location where such location is also more than 10
                  additional miles from Executive's home.


         6. Return of Company Property. All records, plans, manuals, "field
guides", memoranda, lists, documents, statements and other property delivered to
Executive 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 Executive), by
any acquisition candidate of the Company or any other member of the Comfort
Group, and all records compiled by Executive which pertain to the business or
activities of the Company or any other member of the Comfort Group shall be and
remain the property of the Company and shall be subject at all times to its
discretion and control. Likewise, all correspondence with customers,
representatives or acquisition candidates, reports, records, charts, advertising
materials, and any data collected by Executive or by or on behalf of the Company
or any other member of the Comfort Group or any representative of any of them
shall be delivered promptly to the Company without request by it upon
termination of Executive's employment with the Company.

         7. Inventions. Executive shall disclose promptly to the Company any and
all significant conceptions and ideas for inventions, improvements and valuable
discoveries, whether patentable or not, which are conceived or made by
Executive, solely or jointly with another, during the period of Executive's
employment with the Company or within one (1) year thereafter, and which are
directly related to the business or activities of the Company or which Executive
conceives as a result of Executive's employment by the Company. Executive hereby
assigns and agrees to assign all Executive's interests therein to the Company or
its nominee. Whenever requested to do so by the Company, Executive shall execute
any and all applications, assignments or other instruments that the Company
shall deem necessary to apply for and obtain Letters Patent of the United States
or any foreign country or to otherwise protect the Company's interest therein.

         8. Trade Secrets. Executive agrees that Executive will not, during or
after the Term, disclose the specific terms of the Company's or any other member
of the Comfort Group's relationships or agreements with significant vendors or
customers or any other significant and material trade secret of the Company or
any other member of the Comfort Group, whether in existence or proposed, to any
person, firm, partnership, corporation or business for any reason or purpose
whatsoever.

         9. Prior Agreements. This Agreement supercedes any prior documents or
understandings with respect to Executive's employment with the Company.
Executive warrants to the Company that the execution of this Agreement by
Executive and Executive's employment by the Company and the performance of
Executive's duties hereunder will not violate or be a breach of any agreement
with a former employer, client or any other person or entity.

         10. Assignment; Binding Effect. Executive understands that Executive
has been selected for employment by the Company on the basis of Executive's
personal qualifications, experience and skills. Executive agrees, therefore,
that Executive cannot assign all or any portion of Executive's performance under
this Agreement. Executive, Executive's spouse and the estate of


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each shall not have any right to encumber or dispose of any right to receive
payments hereunder, it being understood that such payments and the right thereto
are nonassignable and nontransferable; provided, however, that in the event of
the death of Executive, any payments that Executive is entitled to receive may
be assigned to the beneficiaries of Executive's estate. Subject to the preceding
three (3) sentences and the express provisions of Section 11, this Agreement
shall be binding upon, inure to the benefit of and be enforceable by the parties
hereto and their respective heirs, legal representatives, successors and
assigns.

         11. Complete Agreement. Executive has no oral representations,
understandings or agreements with the Company or any of its officers, directors
or representatives covering the same subject matter as this Agreement. This
Agreement is the final, complete and exclusive statement and expression of the
agreement between the Company and Executive and of all the terms of this
Agreement, and it cannot be varied, contradicted or supplemented by evidence of
any prior or contemporaneous oral or written agreements.

         12. Amendment; Waiver. This Agreement may not be modified except in a
writing signed by the parties, and no term of this Agreement may be waived
except by a writing signed by the party waiving the benefit of such term. No
waiver by the parties hereto of any default or breach of any term, condition or
covenant of this Agreement shall be deemed to be a waiver of any subsequent
default or breach of the same or any other term, condition or covenant contained
herein.

         13. Notice. Whenever any notice is required hereunder, it shall be
given in writing addressed as follows:

         To the Company:  Comfort Systems USA, Inc.
                          777 Post Oak, Suite 500
                          Houston, TX 77056
                          Attention: General Counsel

         To Executive:    Fred Giardenelli, Jr.
                          1240 Milton Keynes Dr.
                          Niskayuna, NY 12309

Notice shall be deemed given and effective on the earlier of five (5) days after
the deposit in the U.S. mail of a writing addressed as above and sent first
class mail, certified, return receipt requested, or when actually received.
Either party may change the address for notice by notifying the other party of
such change in accordance with this Section 13.

         14. Severability; Enforceability. If any portion of this Agreement is
held invalid or inoperative, the other portions of this Agreement shall be
deemed valid and operative and, so far as is reasonable and possible, effect
shall be given to the intent manifested by the portion held invalid or
inoperative. Moreover, in the event any court of competent jurisdiction shall
determine that the scope, time or territorial restrictions set forth in any
covenant contained herein are unreasonable, then it is the intention of the
parties that such restrictions be enforced to the fullest extent which the court
deems reasonable, and this Agreement shall thereby be reformed. Each of the
covenants contained in this Agreement shall be construed as an agreement
independent of any other provision in this Agreement, and the existence of any
claim or cause of action of Executive against the Company,


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whether predicated on this Agreement or otherwise, shall not constitute a
defense to the enforcement by the Company of such covenants.

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

         16. 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, 6, 7 and 8 and because of the immediate and
irreparable damage that could be caused to the Company for which it would have
no other adequate remedy, Executive 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 Executive, by injunctions,
restraining orders and other appropriate equitable relief. Executive further
agrees to waive any requirement for the securing or posting of any bond in
connection with the obtaining of any such injunctive or other equitable relief.

         17. Governing Law. This Agreement shall be governed by and construed in
accordance with the internal laws of the State of New York.

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


EXECUTIVE:                                  COMPANY:

                                            EASTERN HEATING & COOLING, INC.


/s/ Fred Giardenelli, Jr.                   /s/ William George
--------------------------                  ----------------------------------
Fred Giardenelli, Jr.                       Name:  William George
                                            Title:  Vice President


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