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                                                                   EXHIBIT 10.20


                    EIGHTH AMENDMENT dated as of June 30, 2000 (this
                    "Eighth Amendment"), to the Credit Agreement dated
                     ----------------
                    as of December 13, 1995 (as amended prior to the
                    date hereof, the "Credit Agreement"), among Star Gas
                                      ----------------
                    Propane, L.P., a Delaware limited partnership (the
                    "Borrower"), the lenders party thereto, Fleet
                     --------
                    National Bank (formerly known as BankBoston, N.A.),
                    as Administrative Agent (the "Administrative
                                                  --------------
                    Agent"), and Bank of America, N.A. (formerly known
                    -----
                    as NationsBank, N.A.), as Documentation Agent (the
                    "Documentation Agent", and together with the
                     -------------------
                    Administrative Agent, the "Agents").
                                               ------

     The Borrower has requested the Agents and the Lenders to make certain
changes to the Credit Agreement.  The parties hereto have agreed, subject to the
terms and conditions hereof, to amend the Credit Agreement as provided herein.

     Capitalized terms used and not otherwise defined herein shall have the
meanings assigned to such terms in the Credit Agreement (the Credit Agreement,
as amended by, and together with, this Eighth Amendment, and as hereinafter
amended, modified, extended or restated from time to time, being called the
"Amended Agreement").
 -----------------

     Accordingly, the parties hereto hereby agree as follows:

     SECTION 1.01   Amendment to Section 4.03(a). Section 4.03(a) of the Credit
                    ----------------------------
Agreement is hereby deleted in its entirety and the following is hereby
substituted in lieu thereof:

     "(a)  At the time of and immediately after any Tranche B Revolving Credit
Borrowing made or any Tranche B Letter of Credit issued (i) on or before June
30, 1999, the Leverage Ratio as of the date of such Borrowing or issuance (after
giving effect to the acquisition or Growth-Related Capital Expenditure for which
such Borrowing or Letter of Credit is being used) shall be no greater than
5.00:1.00, (ii) after June 30, 1999 and on or before September 30, 1999, the
Leverage Ratio as of the date of such Borrowing or issuance (after giving effect
to the acquisition or Growth-Related Capital Expenditure for which such
Borrowing or Letter of Credit is being used) shall be no greater than 5.25:1.00,
(iii) after September 30, 1999 and on or before November 29, 1999, the Leverage
Ratio as of the date of such Borrowing or issuance (after giving effect to the
acquisition or Growth-Related Capital Expenditure for which such Borrowing or
Letter of Credit is being used) shall be no greater than 5.25:1.00, (iv) after
November 29, 1999 and on or before December 30, 1999, the Leverage Ratio as of
the date of such Borrowing or issuance (after giving effect to the acquisition
or Growth-Related Capital Expenditure for which such Borrowing or Letter of
Credit is being used) shall be no greater than 4.90:1.00 and (v) (A) after
December 30, 1999 and on or before March 30, 2001, the Leverage Ratio as of the
date of
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such Borrowing or issuance (after giving effect to the acquisition or Growth-
Related Capital Expenditure for which such Borrowing or Letter of Credit is
being used) shall be no greater than 5.25:1.00 and (B) after March 30, 2001, the
Leverage Ratio as of the date of such Borrowing or issuance (after giving effect
to the acquisition or Growth-Related Capital Expenditure for which such
Borrowing or Letter of Credit is being used) shall be no greater than 4.50:1.00;
and, in the case of each such Borrowing or issuance of each such Letter of
Credit, the Borrower shall have prepared and furnished to the Agents prior to
such Borrowing or issuance pro forma financial statements demonstrating the
fulfillment of such condition to the satisfaction of the Agents. For purposes of
calculating the Leverage Ratio as required by this Section 4.03(a), Consolidated
Cash Flow for the Reference Period shall mean the greater of (A) Consolidated
Cash Flow for the most recent period of four consecutive fiscal quarters prior
to the date of determination and (B) 50% of Consolidated Cash Flow for the most
recent period of eight consecutive fiscal quarters prior to the date of
determination."

     SECTION 1.02   Amendment to Section 6.31(a).  Section 6.31(a) of the Credit
                    ----------------------------
Agreement is hereby deleted in its entirety and the following is hereby
substituted in lieu thereof:

     "(a)  The Borrower will not permit the ratio on any day (the "date of
determination") of (i) Total Funded Debt as of the last day of the Reference
Period with respect to such date of determination to (ii) Consolidated Cash Flow
for such Reference Period to be greater than the ratio set forth below opposite
the calendar period during which such date of determination occurs:

     Calendar Period                    Ratio
     ---------------                    -----

     January 1, 1996 through            5.00:1.00
     June 30, 1997

     July 1, 1997 through               4.75:1.00
     September 30, 1997

     October 1, 1997 through            4.95:1.00
     December 31, 1997

     January 1, 1998 through            5.00:1.00
     September 30, 1998

     The period ending                  5.40:1.00
     December 31, 1998

     January 1, 1999 through            5.00:1.00
     June 30, 1999

     July 1, 1999 through               5.25:1.00
     September 30, 1999

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     October 1, 1999 through            5.25:1.00
     November 29, 1999

     November 30, 1999 through          4.90:1.00
     December 30, 1999

     December 31, 1999 through          5.25:1.00
     March 30, 2001

     March 31, 2001 and thereafter      4.50:1.00"

     SECTION 1.03   Representations and Warranties.  The Borrower hereby
                    ------------------------------
represents and warrants to each of the Agents and the Lenders, as follows:

          (a) The representations and warranties set forth in Article III of the
     Amended Agreement, and in each other Loan Document, are true and correct in
     all material respects on and as of the date hereof and on and as of the
     Eighth Amendment Effective Date (as hereinafter defined) with the same
     effect as if made on and as of the date hereof or the Eighth Amendment
     Effective Date, as the case may be, except to the extent such
     representations and warranties expressly relate solely to an earlier date.

          (b) Each of the Borrower and the Subsidiaries is in compliance with
     all the terms and conditions of the Amended Agreement and the other Loan
     Documents on its part to be observed or performed and no Default or Event
     of Default has occurred or is continuing.

          (c) The execution, delivery and performance by the Borrower of this
     Eighth Amendment have been duly authorized by the Borrower.

          (d) This Eighth Amendment constitutes the legal, valid and binding
     obligation of the Borrower, enforceable against it in accordance with its
     terms.

          (e) The execution, delivery and performance by the Borrower of this
     Eighth Amendment (i) will not violate (A) any provision of law, statute,
     rule or regulation, or of the agreement of limited partnership of the
     Borrower, (B) any order of any Governmental Authority or (C) any provision
     of any indenture, agreement or other instrument to which the Borrower is a
     party or by which it or any of its property may be bound and (ii) do not
     require any consents under, result in a breach of or constitute (with
     notice or lapse of time or both) a default or give rise to increased,
     additional, accelerated or guaranteed rights of any Person under any such
     indenture, agreement or other instrument.

     SECTION 1.04   Effectiveness.  This Eighth Amendment shall become effective
                    -------------
only upon satisfaction of the following conditions precedent (the first date
upon which each such condition has been satisfied being herein called the
"Eighth Amendment Effective Date"):

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          (a) the Administrative Agent shall have received duly executed
     counterparts of this Eighth Amendment which, when taken together, bear the
     authorized signatures of the Borrower and the Required Lenders.

          (b) The Agents shall be satisfied that the representations and
     warranties set forth in Section 1.06 are true and correct on and as of the
     Eighth Amendment Effective Date.

          (c) There shall not be any action pending or any judgment, order or
     decree in effect which, in the judgment of the Agents or the Lenders, is
     likely to restrain, prevent or impose materially adverse conditions upon
     performance by the Borrower of its obligations under the Amended Agreement.

          (d) The Agents shall have received such other documents, legal
     opinions, instruments and certificates relating to this Eighth Amendment as
     they shall reasonably request and such other documents, legal opinions,
     instruments and certificates shall be satisfactory in form and substance to
     the Agents and the Lenders.  All corporate and other proceedings taken or
     to be taken in connection with this Eighth Amendment and all documents
     incidental thereto, whether or not referred to herein, shall be
     satisfactory in form and substance to the Agents and the Lenders.

          (e) The Borrower shall have paid all fees and expenses referred to in
     Section 1.06 of this Eighth Amendment.

     SECTION 1.05   APPLICABLE LAW.  THIS EIGHTH AMENDMENT SHALL BE GOVERNED BY,
                    --------------
AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK, EXCEPT TO
THE EXTENT THAT THE FEDERAL LAWS OF THE UNITED STATES OF AMERICA MAY APPLY.

     SECTION 1.06   Expenses.  The Borrower shall pay (i) all reasonable out-of-
                    --------
pocket expenses incurred by the Agents and the Lenders in connection with the
preparation, negotiations execution, delivery and enforcement of this Eighth
Amendment, including, but not limited to, the reasonable fees and disbursements
of counsel and (ii) an amendment fee in the aggregate amount of $75,000, payable
pro rata to the Lenders based on their respective Commitments.

     SECTION 1.07   Counterparts.  This Eighth Amendment may be executed in any
                    ------------
number of counterparts, each of which shall constitute an original but all of
which when taken together shall constitute but one agreement.

     SECTION 1.08   Loan Documents.  Except as expressly set forth herein, the
                    --------------
amendments provided herein shall not by implication or otherwise limit,
constitute a waiver of, or otherwise affect the rights and remedies of the
Lenders, the Agents, the Trustee or the other Secured Parties under the Amended
Agreement or any other Loan Document, nor shall they constitute a waiver of any
Default or Event of Default, nor shall they alter, modify, amend or in any way
affect any of the terms, conditions, obligations, covenants or agreements
contained in the Amended Agreement or any other Loan Document. Each of the
amendments provided herein

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shall apply and be effective only with respect to the provisions of the Amended
Agreement specifically referred to by such amendments. Except as expressly
amended herein, the Amended Agreement and the other Loan Documents shall
continue in full force and effect in accordance with the provisions thereof. As
used in the Amended Agreement, the terms "Agreement", "herein", "hereinafter",
"hereunder", "hereto" and words of similar import shall mean, from and after the
date hereof, the Amended Agreement.

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     IN WITNESS WHEREOF, the parties hereto have caused this Eighth Amendment to
be duly executed by duly authorized officers, all as of the date first above
written.


                              STAR GAS PROPANE, L.P., as Borrower

                                   By:  Star Gas LLC, its General Partner


                                        By______________________________________
                                          Name:
                                          Title:


                              FLEET NATIONAL BANK (formerly known as BankBoston,
                              N.A.), as Administrative Agent and as a Lender


                              By________________________________________________
                                Name:
                                Title:


                              BANK OF AMERICA, N.A., as Documentation Agent
                              and as a Lender


                              By________________________________________________
                                Name:
                                Title:

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