UNITED STATES
                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549

                                 SCHEDULE 13G


                   Under the Securities Exchange Act of 1934


                           Comfort Systems USA, Inc.

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                               (Name of Issuer)


                                 COMMON STOCK
--------------------------------------------------------------------------------
                          (Title of Class Securities)


                                  199908104
                     ------------------------------------
                                (CUSIP Number)


                              February 15, 2005
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            (Date of Event Which Requires Filing of this Statement)


Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

      |_|   Rule 13d-1(b)

      |X|   Rule 13d-1(c)

      |_|   Rule 13d-1(d)

*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosure provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).



.........................
CUSIP No.  199908104
.........................

--------------------------------------------------------------------------------
      Name of Reporting Persons.
1     I.R.S. Identification Nos. of above persons (entities only).

      Cannell Capital LLC
      94-3366999

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      Check the Appropriate Box if a Member of a Group (See Instructions)
2
      (a)  |X|

      (b)

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--------------------------------------------------------------------------------
      SEC Use Only
3

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      Citizenship or Place of Organization
4
      California

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              5    Sole Voting Power




  number of
   shares
beneficially
  owned by
    each
  reporting
 person with


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              6    Shared Voting Power

                   2,385,000
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              7    Sole Dispositive Power


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              8    Shared Dispositive Power

                   2,385,000
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

9     Aggregate Amount Beneficially Owned by Each Reporting Person

      2,385,000
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

10    Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See
a      Instructions)


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

11    Percent of Class Represented by Amount in Row (9)
      6.1%
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

12    Type  of Reporting Person (See Instructions)
      IA
--------------------------------------------------------------------------------


.........................
CUSIP No.  199908104
.........................

--------------------------------------------------------------------------------
      Name of Reporting Persons.
1     I.R.S. Identification Nos. of above persons (entities only).

      J. Carlo Cannell

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      Check the Appropriate Box if a Member of a Group (See Instructions)
2
      (a)  |X|

      (b)


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      SEC Use Only
3

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      Citizenship or Place of Organization
4
      USA

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              5    Sole Voting Power




  number of
   shares
beneficially
  owned by
    each
  reporting
 person with


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              6    Shared Voting Power

                   2,385,000
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              7    Sole Dispositive Power


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              8    Shared Dispositive Power

                   2,385,000
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

9     Aggregate Amount Beneficially Owned by Each Reporting Person

      2,385,000
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

10    Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See
      Instructions)


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

11    Percent of Class Represented by Amount in Row (9)
      6.1%
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

12    Type  of Reporting Person (See Instructions)
      IN, HC
--------------------------------------------------------------------------------


.........................
CUSIP No.  199908104
.........................

--------------------------------------------------------------------------------
      Name of Reporting Persons.
1     I.R.S. Identification Nos. of above persons (entities only).

      The Anegada Master Fund Limited

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      Check the Appropriate Box if a Member of a Group (See Instructions)
2
      (a) |X|

      (b)

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      SEC Use Only
3

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      Citizenship or Place of Organization
4
      Cayman Islands

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              5    Sole Voting Power




  number of
   shares
beneficially
  owned by
    each
  reporting
 person with


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              6    Shared Voting Power

                   513,700
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              7    Sole Dispositive Power


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              8    Shared Dispositive Power

                   513,700
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

9     Aggregate Amount Beneficially Owned by Each Reporting Person

      513,700
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

10    Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See
      Instructions)


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

11    Percent of Class Represented by Amount in Row (9)
      1.3%
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

12    Type  of Reporting Person (See Instructions)
      CO
--------------------------------------------------------------------------------


.........................
CUSIP No.  199908104
.........................

--------------------------------------------------------------------------------
      Name of Reporting Persons.
1     I.R.S. Identification Nos. of above persons (entities only).

      The Cuttyhunk Fund Limited


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      Check the Appropriate Box if a Member of a Group (See Instructions)
2
      (a)  |X|

      (b)

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      SEC Use Only
3

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      Citizenship or Place of Organization
4
      Bermuda

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              5    Sole Voting Power




  number of
   shares
beneficially
  owned by
    each
  reporting
 person with


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              6    Shared Voting Power

                   614,781
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              7    Sole Dispositive Power


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              8    Shared Dispositive Power

                   614,781
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

9     Aggregate Amount Beneficially Owned by Each Reporting Person

      614,781
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

10    Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See
      Instructions)


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

11    Percent of Class Represented by Amount in Row (9)
      1.6%
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

12    Type  of Reporting Person (See Instructions)
      CO
--------------------------------------------------------------------------------


.........................
CUSIP No.  199908104
.........................

--------------------------------------------------------------------------------
      Name of Reporting Persons.
1     I.R.S. Identification Nos. of above persons (entities only).

      Tonga Partners, L.P.
      94-3164039

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      Check the Appropriate Box if a Member of a Group (See Instructions)
2
      (a)  |X|

      (b)


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      SEC Use Only
3

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      Citizenship or Place of Organization
4
      Delaware

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              5    Sole Voting Power



  number of
   shares
beneficially
  owned by
    each
  reporting
 person with


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              6    Shared Voting Power

                   760,919
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              7    Sole Dispositive Power


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              8    Shared Dispositive Power

                   760,919
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

9     Aggregate Amount Beneficially Owned by Each Reporting Person

      760,919
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

10    Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See
      Instructions)


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

11    Percent of Class Represented by Amount in Row (9)
      1.9%
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

12    Type  of Reporting Person (See Instructions)
      PN
--------------------------------------------------------------------------------


.........................
CUSIP No.  199908104
.........................

--------------------------------------------------------------------------------
      Name of Reporting Persons.
1     I.R.S. Identification Nos. of above persons (entities only).

      GS Cannell Portfolio, LLC
      98-0232642

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      Check the Appropriate Box if a Member of a Group (See Instructions)
2
      (a) |X|

      (b)

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      SEC Use Only
3

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      Citizenship or Place of Organization
4
      Delaware

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              5    Sole Voting Power




  number of
   shares
beneficially
  owned by
    each
  reporting
 person with


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              6    Shared Voting Power

                   343,900
-------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              7    Sole Dispositive Power


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              8    Shared Dispositive Power

                   343,900
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

9     Aggregate Amount Beneficially Owned by Each Reporting Person

      343,900
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

10    Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See
      Instructions)


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

11    Percent of Class Represented by Amount in Row (9)
      0.9%
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

12    Type  of Reporting Person (See Instructions)
      OO
--------------------------------------------------------------------------------


.........................
CUSIP No.  199908104
.........................

--------------------------------------------------------------------------------
      Name of Reporting Persons.
1     I.R.S. Identification Nos. of above persons (entities only).

      Pleiades Investment Partners, L.P.
      23-2688812

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      Check the Appropriate Box if a Member of a Group (See Instructions)
2
      (a)  |X|

      (b)

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      SEC Use Only
3

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
      Citizenship or Place of Organization
4
      Delaware

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              5    Sole Voting Power




  number of
   shares
beneficially
  owned by
    each
  reporting
 person with


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              6    Shared Voting Power

                   151,700
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              7    Sole Dispositive Power


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

              8    Shared Dispositive Power

                   151,700
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

9     Aggregate Amount Beneficially Owned by Each Reporting Person

      151,700
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

10    Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See
      Instructions)


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

11    Percent of Class Represented by Amount in Row (9)
      0.4%
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

12    Type  of Reporting Person (See Instructions)
      PN
--------------------------------------------------------------------------------




Item 1.

    (a) Name of Issuer

        Comfort Systems USA, Inc.


    (b) Address of Issuer's Principal Executive Offices

        777 Post Oak Boulevard, Suite 500
        Houston, TX 77056

Item 2.

    (a) Name of Person Filing

        This statement is being filed by (i) Cannell Capital, LLC, a California
        limited liability company and California licensed investment adviser
        ("IA"), (ii) J. Carlo Cannell ("Managing Member"), (iii) The Anegada
        Master Fund Limited ("Anegada"), (iv) The Cuttyhunk Fund Limited
        ("Cuttyhunk"), (v) Tonga Partners, L.P. ("Tonga"), (vi) GS Cannell
        Portfolio, LLC ("GS Cannell") and (vii) Pleiades Investment Partners, LP
        ("Pleiades") (collectively, the Reporting Persons). Managing Member
        controls IA by virtue of Managing Member's position as managing member
        and majority owner of IA.

        IA's beneficial ownership of the Common Stock is direct as a result of
        IA's discretionary authority to buy, sell, and vote shares of such
        Common Stock for its investment advisory clients. Managing Member's
        beneficial ownership of Common Stock is indirect as a result of Managing
        Member's ownership and management of IA. The beneficial ownership of
        Managing Member is reported solely because Rules 13d-1(a) and (c) under
        the Securities Exchange Act of 1934, as amended, require any person who
        is "directly or indirectly" the beneficial owner of more than five
        percent of any equity security of a specified class to file a Schedule
        13G. The answers in blocks 6, 8, 9 and 11 above and the response to item
        4 by Managing Member are given on the basis of the "indirect" beneficial
        ownership referred to in such Rule, based on the direct beneficial
        ownership of Common Stock by IA and the relationship of Managing Member
        to IA referred to above.

        Information with respect to each Reporting Person is given solely by the
        respective Reporting Person, and no Reporting Person undertakes hereby
        any responsibility for the accuracy or completeness or such information
        concerning any other Reporting Person.


    (b) Address of Principal Business office or, if None, Residence

        IA's principal business office is located at:
        150 California Street, Fifth Floor, San Francisco, CA 94111

        Managing Member's principal business office is located at:
        150 California Street, Fifth Floor, San Francisco, CA 94111

        Anegada's principal business office is located at:
        c/o Bank of Butterfield International (Cayman) Ltd., 68
        Fort Street, PO Box 705, George Town, Grand Cayman, Cayman Islands

        Cuttyhunk's principal business office is located at:
        73 Front Street, Hamilton, Bermuda HM 12

        Tonga's principal business office is located at:
        150 California Street, Fifth Floor, San Francisco, CA 94111

        GS Cannell's principal business office is located at:
        701 Mount Lucas Road, CN 850, Princeton, NJ 08542

        Pleiades' principal business office is located at:
        6022 West Chester Pike, Newtown Square, PA 19073


    (c) Citizenship

        Item 4 of each cover page is incorporated by reference

    (d) Title of Class Securities

        Common

    (e) CUSIP Number

        199908104

Item 3. If this statement is filed pursuant to ss 240.13d-1(b), or ss
        240.13d-2(b) or (c), check whether the person filing is a:

        (a)    Broker or dealer registered under section 15 of the Act (15
               U.S.C. 78o).
        (b)    Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).
        (c)    Insurance company as defined in section 3(a)(19) of the Act
               (15 U.S.C. 78c).
        (d)    Investment company registered under section 8 of the
               Investment Company Act (15 U.S.C. 80a-8).
        (e)    An investment adviser in accordance with ss
               240.13d-1(b)(1)(ii)(E).
        (f)    An employee benefit plan or endowment fund in accordance with
               ss 240.13d-1(b)(ii)(F).
        (g)    A parent holding company or control person in accordance with
               ss 240.13d-1(b)(1)(ii)(G).
        (h)    A savings association as defined in Section 3(b) of the
               Federal Deposit Insurance Act (12 U.S.C. 1813).
        (i)    A church plan that is excluded from the definition of an
               investment company under section 3(c)(14) of the Investment
               Company Act of 1940 (15 U.S.C. 80a-3).
        (j)    Group in accordance with ss 240.13d-1(b)(ii)(J).

Item 4. Ownership

        Common Stock:

        Items 5-9 and 11 of each cover sheet are incorporated by reference.


Item 5. Ownership of Five Percent or Less of a Class.

        If this statement is being filed to report the fact that as of the date
        hereof the reporting person has ceased to be the beneficial owner of
        more than five percent of the class securities, check the following | |

Item 6. Ownership of More than Five Percent on Behalf of Another Person.

        IA, a California licensed investment advisor, and Managing Member, the
        majority owner and managing member of IA, have the right or the power to
        direct the receipt of dividends from Common Stock, and to direct the
        receipt of proceeds from the sale of Common Stock to IA's investment
        advisory clients. No single investment advisory client of IA owns more
        than 5% of the Common Stock.

Item 7. Identification and Classification of the Subsidiary Which Acquired the
        Security Being Reported on By the Parent Holding Company.

        Not Applicable

Item 8. Identification of Members of the Group.

        Not Applicable

Item 9. Notice of Dissolution of Group.

        Not Applicable.

Item 10.    Certification:

            By signing below I certify that, to the best of my knowledge and
            belief, the securities referred to above were not acquired and are
            not held for the purpose of or with the effect of changing or
            influencing the control of the issuer of the securities and were not
            acquired and are not held in connection with or as a participant in
            any transaction having that purpose or effect.


                                   SIGNATURE
Date:  February 25, 2005
                               CANNELL CAPITAL LLC

                                     /s/ J. Carlo Cannell
                          ------------------------------------------
                              J. Carlo Cannell, Managing Member

                          J. CARLO CANNELL

                                     /s/ J. Carlo Cannell
                          ------------------------------------------
                                       J. Carlo Cannell

                          THE ANEGADA MASTER FUND LIMITED

                                     /s/ J. Carlo Cannell
                          ------------------------------------------
                              J. Carlo Cannell, Managing Member
                            Cannell Capital LLC, Investment Adviser

                          THE CUTTYHUNK FUND LIMITED

                                     /s/ J. Carlo Cannell
                          ------------------------------------------
                              J. Carlo Cannell, Managing Member
                            Cannell Capital LLC, Investment Adviser

                          TONGA PARTNERS, L.P.

                                     /s/ J. Carlo Cannell
                          ------------------------------------------
                              J. Carlo Cannell, Managing Member
                            Cannell Capital LLC, General Partner

                          GS CANNELL PORTFOLIO, LLC

                                     /s/ J. Carlo Cannell
                          ------------------------------------------
                              J. Carlo Cannell, Managing Member
                            Cannell Capital LLC, Investment Adviser

                          PLEIADES INVESTMENT PARTNERS, LP

                                     /s/ J. Carlo Cannell
                          ------------------------------------------
                              J. Carlo Cannell, Managing Member
                            Cannell Capital LLC, Investment Adviser



EXHIBIT A


           Identification of Members of the Group


Pursuant to Rule 13d-1(c)under the Securities and Exchange Act of 1934, the
members of the group making this joint filing are identified as follows:

Not Applicable

EXHIBIT B

                 Joint Filing Agreement Pursuant to Rule 13d-1

This agreement is made pursuant to Rule 13d-1(b)(ii)(J) and Rule 13d-1(k)(1)
under the Securities and Exchange Act of 1934 (the "Act") by and among the
parties listed below, each referred to herein as a "Joint Filer." The Joint
Filers agree that a statement of beneficial ownership as required by Sections
13(g) or 13(d) of the Act and the Rules thereunder may be filed on each of their
behalf on Schedule 13G or Schedule 13D, as appropriate, and that said joint
filing may thereafter be amended by further joint filings. The Joint Filers
state that they each satisfy the requirements for making a joint filing under
Rule 13d-1.

Dated:  February 25, 2005

                               CANNELL CAPITAL LLC

                                     /s/ J. Carlo Cannell
                          ------------------------------------------
                              J. Carlo Cannell, Managing Member

                          J. CARLO CANNELL

                                     /s/ J. Carlo Cannell
                          ------------------------------------------
                                       J. Carlo Cannell

                          THE ANEGADA MASTER FUND LIMITED

                                     /s/ J. Carlo Cannell
                          ------------------------------------------
                              J. Carlo Cannell, Managing Member
                            Cannell Capital LLC, Investment Adviser

                          THE CUTTYHUNK FUND LIMITED

                                     /s/ J. Carlo Cannell
                          ------------------------------------------
                              J. Carlo Cannell, Managing Member
                            Cannell Capital LLC, Investment Adviser

                          TONGA PARTNERS, L.P.

                                     /s/ J. Carlo Cannell
                          ------------------------------------------
                              J. Carlo Cannell, Managing Member
                            Cannell Capital LLC, General Partner

                          GS CANNELL PORTFOLIO, LLC

                                     /s/ J. Carlo Cannell
                          ------------------------------------------
                              J. Carlo Cannell, Managing Member
                            Cannell Capital LLC, Investment Adviser

                          PLEIADES INVESTMENT PARTNERS, LP

                                     /s/ J. Carlo Cannell
                          ------------------------------------------
                              J. Carlo Cannell, Managing Member
                            Cannell Capital LLC, Investment Adviser