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                                                                    EXHIBIT 10.4


                               FIRST AMENDMENT TO
                       LIMITED LIABILITY COMPANY AGREEMENT

      THIS FIRST AMENDMENT TO LIMITED LIABILITY COMPANY AGREEMENT (this
"Amendment") of R4 Technical Center - North Carolina, LLC, a Delaware limited
liability company (the "Company"), is entered into as of September 30, 2001 (the
"Effective Date"), by and among Blue Rhino Corporation, a Delaware corporation
("BRC"), Manchester Tank & Equipment Co., a Delaware corporation ("Manchester"),
and Platinum Propane, L.L.C., a Delaware limited liability company ("Platinum").

                                    RECITALS

      A. Each of BRC, Manchester and Platinum previously entered into that
certain Limited Liability Company Agreement dated April 28, 2000 (the
"Agreement") in order to organize and provide for the operation and management
of the Company.

      B. The parties wish to amend the Agreement in accordance with the terms
and conditions hereof.

                                    AGREEMENT

      NOW, THEREFORE, in consideration of the mutual promises and covenants
contained herein, the parties hereto agree that the Agreement is amended as
follows:

      1. Definitions. Unless otherwise defined herein, capitalized terms shall
have the meanings accorded to them in the Agreement.

      2. Amendment to Section 7.12 of the Agreement. Section 7.12 of the
Agreement is hereby replaced in its entirety with the following:

            Section 7.12 Default Repurchase Rights.

            (a) If a Member commits a material default (a "Defaulting Member")
      under the provisions of this Agreement or any other material agreement or
      arrangement with another Member (other than the Master Lease Agreement
      described in subsection (b) below), and such default is not cured within
      30 days after written notice of such default, the remaining Members who
      choose to purchase, on a basis proportionate to the ratio that their Units
      bear to all outstanding Units owned by those Members that choose to
      purchase (other than the Units of the Defaulting Member) shall have the
      right to purchase all (but not less than all) of the Units of the
      Defaulting Member for the lesser of the Defaulting Member's Capital
      Account or the value obtained pursuant to the procedures set forth in
      Section 7.8 (for purposes of this Section 7.12(a), the Defaulting Member
      shall be deemed to have incurred a "Change in Control"). The
      non-Defaulting Member shall give the Defaulting Member notice of its
      intention to exercise its repurchase right in this Section 7.12 within
      thirty (30) days after the Defaulting Member failed to cure any such
      default.
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      In determining the purchase price pursuant to this Section, the
      purchasing Members shall have the right to set-off against the purchase
      price all amounts owed to them (or the Company) by the Defaulting Member.
      Notwithstanding anything to the contrary contained herein, in the event of
      a default by the Distributor Member Section 7.5(d) shall control.

            (b) In the event that BRC exercises one of its remedies (each, a
      "Lease Remedy") under Section 20.2 of that certain Master Lease Agreement
      effective September 30, 2001 by and between the Company, as lessee, and
      BRC, as lessor, as may be amended from time to time (the "Master Lease"),
      following an "Event of Default" (as defined thereunder), then at the
      election of Manchester, in its sole discretion, BRC shall have the
      obligation to purchase all (but not less than all) of the Units of
      Manchester for the value determined pursuant to Section 7.8 (in which
      case, for purposes of this Section 7.12(b), Manchester shall be deemed to
      have incurred a "Change in Control"); provided, however, in determining
      the value of Manchester's Units in the Company under Section 7.8, such
      value shall be determined as though such Event of Default had not
      occurred. Manchester shall give BRC notice of its election to compel BRC's
      purchase of Manchester's Units under this Section 7.12(b) within ten (10)
      days after BRC provides Manchester with written notice of BRC's intent to
      exercise a Lease Remedy and, in such event, BRC shall purchase
      Manchester's Units not more than sixty (60) days following the date value
      is determined pursuant to Section 7.8.

      3. Full Force and Effect. Except as hereby expressly amended and modified,
the Agreement shall remain in full force and effect.
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      IN WITNESS WHEREOF, the parties hereto have executed this Amendment as of
the Effective Date.


                                    BLUE RHINO CORPORATION, a Delaware
                                    corporation


                                    By: /s/ Billy Prim
                                        --------------------------------------
                                          Its: President
                                               -------------------------------


                                    MANCHESTER TANK & EQUIPMENT CO., a
                                    Delaware corporation


                                    By:  /s/ Charles F. Nowlin
                                         -------------------------------------
                                          Its: Vice President
                                               -------------------------------


                                    PLATINUM PROPANE, L.L.C., a Delaware
                                    limited liability company


                                    By:      /s/ Daryl F. McClendon
                                         -------------------------------------
                                          Its: General Manager
                                               -------------------------------