1
                                                                  Exhibit 10.1.5

                 FIFTH AMENDMENT AND WAIVER TO CREDIT AGREEMENT

          FIFTH AMENDMENT AND WAIVER TO CREDIT AGREEMENT, dated as of March 30,
2001 (this "Amendment"), among AMTROL HOLDINGS, INC., a Delaware corporation
("Holdings"), AMTROL INC., a Rhode Island corporation (the "Borrower"), the
various financial institutions party to the Credit Agreement referred to below
(the "Banks"), MORGAN STANLEY SENIOR FUNDING, INC., as Documentation Agent (in
such capacity, the "Documentation Agent"), and BANKERS TRUST COMPANY, as
Administrative Agent (in such capacity, the "Administrative Agent"). All
capitalized terms used herein and not otherwise defined shall have the
respective meanings provided such terms in the Credit Agreement referred to
below.

                              W I T N E S S E T H :
                              - - - - - - - - - -

          WHEREAS, Holdings, the Borrower, the Banks, the Documentation Agent
and the Administrative Agent are parties to a Credit Agreement, dated as of
November 13, 1996 (as amended, modified or supplemented to the date hereof, the
"Credit Agreement"); and

          WHEREAS, subject to the terms and conditions of this Amendment, the
parties hereto wish to amend, and the Banks party hereto wish grant a waiver to
certain provisions of, the Credit Agreement, in each case as herein provided;

          NOW, THEREFORE, it is agreed:

I.   AMENDMENTS TO CREDIT AGREEMENT.

          1.   Section 3.03(d) of the Credit Agreement is hereby amended by
deleting the date "November 13, 2001" appearing in the table in said Section and
inserting the date "March 30, 2001" in lieu thereof.

          2.   Section 4.02(A)(e) of the Credit Agreement is hereby amended by
(i) deleting the second parenthetical appearing in said Section and inserting
the text "(other than (x) proceeds from any Capital Call Contribution made
pursuant to the Capital Contribution Agreement, (y) equity issued to management
and other employees of Holdings and its Subsidiaries as provided for in Section
8.09(a)(ii) and (z) in connection with the Equity Financing)" in lieu thereof
and (ii) inserting the text "(excluding any capital contribution received by the
Borrower from Holdings and made by Holdings with the proceeds of any Capital
Call Contribution pursuant to the Capital Contribution Agreement)" immediately
after the text "with any capital contributions" appearing in said Section.

          3.   Section 4.02(A) of the Credit Agreement is hereby amended by
inserting the following new clause (j) at the end of said Section:

          "(j) On the date on which the Borrower receives any cash proceeds
     pursuant to a capital contribution from Holdings made with the proceeds of
     a Capital Call Contribution

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     pursuant to the Capital Contribution Agreement, an amount equal to 100% of
     such cash proceeds shall be applied as a mandatory repayment of principal
     of the then outstanding Loans; PROVIDED that, notwithstanding the
     foregoing, cash proceeds in an amount equal to only 50% of the Capital Call
     Contribution Amount of the respective Capital Call Contribution shall be
     applied as a mandatory repayment of principal of the then outstanding
     Loans, so long as (i) no Default or Event of Default is then in existence
     or would result therefrom and (ii) any cash proceeds not required to be
     applied to repay Loans as a result of the application of this proviso are
     applied to repurchase Senior Subordinated Notes pursuant to, and in
     accordance with the terms of, Section 8.08(a); PROVIDED FURTHER that any
     cash proceeds not so used to repurchase Senior Subordinated Notes as
     contemplated by the preceding proviso within the time period specified in
     Section 8.08(a) shall be applied as a mandatory repayment of principal of
     the then outstanding Loans as provided above (without regard to the
     preceding proviso);".

          4.   Section 4.02(B)(a) of the Credit Agreement is hereby amended by
(i) deleting the text "to clause (b)" appearing in said Section and inserting
the text "to clauses (b) and (for purposes of succeeding subclause (x) only)
(j)" in lieu thereof and (ii) inserting the following sentence at the end of
said Section:

          "Each mandatory repayment of Loans required to be made pursuant to
     Section 4.02(A)(j) shall be applied (I) in the event Revolving Loans are
     outstanding at the time of such repayment, to the A Term Loans in an amount
     equal to the A TF Capital Call Percentage of such prepayment, to the B Term
     Loans in an amount equal to the B TF Capital Call Percentage of such
     prepayment and to the Revolving Loans in an amount equal to the Revolving
     Capital Call Percentage of such prepayment (but subject to clause (II)
     below in the event all Revolving Loans are repaid as a result of the
     application of this clause (I)) and (II) in the event no Revolving Loans
     are outstanding at the time of such repayment (or all outstanding Revolving
     Loans have been repaid in full as a result of the application of preceding
     clause (I), then any excess amount of such mandatory repayment shall be
     applied), to the A Term Loans in an amount equal to the A TF Percentage of
     such prepayment and to the B Term Loans in an amount equal to the B TF
     Percentage of such prepayment.".

          5.   Section 7 of the Credit Agreement is hereby amended by inserting
the following new Section 7.16 at the end of said Section:

          "7.16 CONTRIBUTIONS. Holdings will contribute as an equity
     contribution to the capital of the Borrower upon its receipt thereof, all
     cash proceeds and Senior Subordinated Notes received by it from the Fund or
     any other Person as a Capital Call Contribution pursuant to the Capital
     Contribution Agreement.".

          6.   Section 8.02(f) of the Credit Agreement is hereby amended by (i)
deleting the word "and" appearing immediately prior to the text "(II) any other"
appearing in said Section and inserting a comma in lieu thereof, (ii) inserting
the text "and (III) any other assets comprising all or a portion of a business
which has negative "EBITDA" for the four fiscal quarters immediately preceding
March 30, 2001 or otherwise identified by the Borrower to the

                                      -2-
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Administrative Agent on March 30, 2001" immediately after the text "$500,000 in
any fiscal year of the Borrower" appearing in said Section and (iii) deleting
the text "and (f)(II)" appearing in said Section and inserting the text
",(f)(II) and (f)(III)" in lieu thereof.

          7.   Section 8.06(g) of the Credit Agreement is hereby amended by
inserting the following text at the end of said Section:

          ", so long as calculations are made by Holdings (and delivered to the
     Administrative Agent) of compliance with the covenants contained in
     Sections 8.11, 8.12 and 8.13 for the period of four consecutive fiscal
     quarters (taken as one accounting period) most recently ended prior to the
     date of such Permitted Acquisition (each, a "Calculation Period"), on a PRO
     FORMA Basis as if the respective Permitted Acquisition (as well as all
     other Permitted Acquisitions theretofore consummated after the first day of
     such Calculation Period) had occurred on the first day of such Calculation
     Period".

          8.   Section 8.08(a) of the Credit Agreement is hereby amended by
inserting the following proviso immediately after the text "of the Senior
Subordinated Notes" appearing in said Section:

          "; PROVIDED that (i) Senior Subordinated Notes may be repurchased on
     the open market with the cash proceeds of any Capital Call Contribution not
     required to be applied as a mandatory repayment of Loans pursuant to
     Section 4.02(A)(j), so long as (x) no Default or Event of Default then
     exists or would result therefrom, (y) such repurchase is made within
     fifteen Business Days following the receipt of such proceeds and (z) any
     such repurchase of Senior Subordinated Notes is made for no more than the
     face amount of such Senior Subordinated Notes and (ii) the Borrower may
     retire and cancel Senior Subordinated Notes contributed to it (through
     Holdings) pursuant to any Capital Call Contribution, so long as no Default
     or Event of Default then exists or would result therefrom".

          9.   Section 8.11 of the Credit Agreement is hereby amended by (i)
deleting the text "the ratio of (i) Consolidated EBITDA to (ii) Consolidated
Cash Interest Expense" appearing in said Section and inserting the text
"Interest Coverage Ratio" in lieu thereof, (ii) deleting the table appearing in
said Section in its entirety and inserting in lieu thereof the following new
table:

          "Fiscal Quarter Ending Closest To:     Ratio
          ----------------------------------     --------

          December 31, 1996                      1.60:1.0

          March 31, 1997                         1.60:1.0
          June 30, 1997                          1.60:1.0
          September 30, 1997                     1.60:1.0
          December 31, 1997                      1.55:1.0

          March 31, 1998                         1.55:1.0
          June 30, 1998                          1.35:1.0

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          September 30, 1998                     1.35:1.0
          December 31, 1998                      1.35:1.0

          March 31, 1999                         1.35:1.0
          June 30, 1999                          1.35:1.0
          September 30, 1999                     1.45:1.0
          December 31, 1999                      1.50:1.0

          March 31, 2000                         1.50:1.0
          June 30, 2000                          1.55:1.0
          September 30, 2000                     1.60:1.0
          December 31, 2000                      1.65:1.0

          June 30, 2001                          1.35:1.0
          September 30, 2001                     1.30:1.0
          December 31, 2001                      1.30:1.0

          March 31, 2002                         1.45:1.0
          June 30, 2002                          1.90:1.0
          September 30, 2002                     1.95:1.0
          December 31, 2002                      2.00:1.0

          March 31, 2003                         2.10:1.0
          June 30, 2003                          2.15:1.0
          September 30, 2003                     2.25:1.0
          December 31, 2003                      2.30:1.0

          March 31, 2004                         2.35:1.0
          June 30, 2004                          2.50:1.0"

and (iii) inserting the following sentence at the end of said Section:

          "Notwithstanding anything to the contrary contained in this Agreement,
     all calculations of compliance with this Section 8.11 shall be made on a
     PRO FORMA Basis.".

          10.  The Banks hereby waive any Default or Event of Default that has
arisen pursuant to Section 9.03 of the Loan Agreement solely as a result of the
failure of the Borrower to comply with the financial covenant contained in
Section 8.11 (as in effect prior to the Fifth Amendment Effective Date) for (and
only for) the fiscal quarter ended March 31, 2001.

          11.  Section 8.12 of the Credit Agreement is hereby amended by (i)
deleting the table appearing in said Section in its entirety and inserting in
lieu thereof the following new table:

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          "Fiscal Quarter Ending Closest To:     Ratio
          ----------------------------------     --------

          December 31, 1996                      6.25:1.0

          March 31, 1997                         6.25:1.0
          June 30, 1997                          6.25:1.0
          September 30, 1997                     6.25:1.0
          December 31, 1997                      6.40:1.0

          March 31, 1998                         6.60:1.0
          June 30, 1998                          7.80:1.0
          September 30, 1998                     7.80:1.0
          December 31, 1998                      7.80:1.0

          March 31, 1999                         7.80:1.0
          June 30, 1999                          7.75:1.0
          September 30, 1999                     7.25:1.0
          December 31, 1999                      6.75:1.0

          March 31, 2000                         6.50:1.0
          June 30, 2000                          6.50:1.0
          September 30, 2000                     6.25:1.0
          December 31, 2000                      5.85:1.0

          June 30, 2001                          6.75:1.0
          September 30, 2001                     6.50:1.0
          December 31, 2001                      6.25:1.0

          March 31, 2002                         6.00:1.0
          June 30, 2002                          5.25:1.0
          September 30, 2002                     4.75:1.0
          December 31, 2002                      4.50:1.0

          March 31, 2003                         4.50:1.0
          June 30, 2003                          4.50:1.0
          September 30, 2003                     4.40:1.0
          December 31, 2003                      4.20:1.0

          March 31, 2004                         3.80:1.0
          June 30, 2004                          3.25:1.0"

and (ii) inserting the following sentence at the end of said Section:

          "Notwithstanding anything to the contrary contained in this Agreement,
     all calculations of compliance with this Section 8.12 shall be made on a
     PRO FORMA Basis.".

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          12.  The Banks hereby waive any Default or Event of Default that has
arisen pursuant to Section 9.03 of the Loan Agreement solely as a result of the
failure of the Borrower to comply with the financial covenant contained in
Section 8.12 (as in effect prior to the Fifth Amendment Effective Date) for (and
only for) the fiscal quarter ended March 31, 2001.

          13.  Section 8.13 of the Credit Agreement is hereby amended by (i)
deleting the table appearing in said Section in its entirety and inserting in
lieu thereof the following new table:

          "Fiscal Quarter Ending Closest To:     Amount
          ----------------------------------     -----------

          December 31, 1996                      $27,800,000

          March 31, 1997                         $26,640,000
          June 30, 1997                          $26,640,000
          September 30, 1997                     $26,640,000
          December 31, 1997                      $26,640,000

          March 31, 1998                         $27,330,000
          June 30, 1998                          $25,000,000
          September 30, 1998                     $25,000,000
          December 31, 1998                      $25,000,000

          March 31, 1999                         $25,000,000
          June 30, 1999                          $25,000,000
          September 30, 1999                     $26,000,000
          December 31, 1999                      $27,000,000

          March 31, 2000                         $27,000,000
          June 30, 2000                          $28,000,000
          September 30, 2000                     $28,500,000
          December 31, 2000                      $29,500,000

          June 30, 2001                          $23,000,000
          September 30, 2001                     $22,000,000
          December 31, 2001                      $21,000,000

          March 31, 2002                         $22,000,000
          June 30, 2002                          $34,000,000
          September 30, 2002                     $34,500,000
          December 31, 2002                      $35,000,000

          March 31, 2003                         $36,000,000
          June 30, 2003                          $37,000,000
          September 30, 2003                     $37,500,000
          December 31, 2003                      $38,500,000

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          March 31, 2004                         $39,000,000
          June 30, 2004                          $39,500,000"

and (ii) inserting the following sentence at the end of said Section:

          "Notwithstanding anything to the contrary contained in this Agreement,
     all calculations of compliance with this Section 8.13 shall be made on a
     PRO FORMA Basis.".

          14.  The Banks hereby waive any Default or Event of Default that has
arisen pursuant to Section 9.03 of the Loan Agreement solely as a result of the
failure of the Borrower to comply with the financial covenant contained in
Section 8.13 (as in effect prior to the Fifth Amendment Effective Date) for (and
only for) the fiscal quarter ended March 31, 2001.

          15.  Section 8 of the Credit Agreement is hereby amended by inserting
the following new Section 8.16 at the end of said Section:

          "8.16 FINANCIAL COVENANT CURE. Notwithstanding anything to the
     contrary contained in Section 8.11 or 8.12, in the event that (I) (i)
     Holdings' Interest Coverage Ratio for any Test Period ending on the last
     day of any fiscal quarter of Holdings set forth in Section 8.11 is less
     than the ratio set forth opposite such fiscal quarter in Section 8.11 or
     (ii) Holdings' Leverage Ratio on the last day of any fiscal quarter set
     forth in Section 8.12 is greater than the amount set forth opposite such
     fiscal quarter and (II) the Fund shall have made a capital contribution to
     Holdings in such amount and at such times as may be required by Section 2
     of the Capital Contribution Agreement (each such contribution, a "Capital
     Call Contribution"), compliance with the covenants contained in Sections
     8.11 and 8.12 shall be recalculated on a PRO FORMA Basis to give effect to
     the repayment of any Loans which shall have been repaid at such time
     pursuant to Section 4.02(A)(j) and to the repurchase or retirement of any
     Senior Subordinated Notes which shall have been repurchased or retired at
     such time.".

          16.  Section 9.03 of the Credit Agreement is hereby amended by (i)
inserting the text "(other than, at any time prior (and only prior) to March 31,
2002, Sections 8.11 and 8.12)" immediately after the text "or 8" appearing in
clause (a) of said Section, (ii) redesignating clause (b) of said Section as
clause (c) thereof, (iii) inserting the text "or (b)" immediately after the text
"or clause (a)" appearing in clause (c) of said Section (as redesignated
pursuant to clause (ii) above) and (iv) inserting the following new clause (b)
after clause (a) appearing in said Section:

          "(b) at any time prior to March 31, 2002, default in the due
     performance or observance by it of any agreement or covenant contained in
     Section 8.11 or 8.12 and such default shall continue unremedied for period
     of at least 45 days (in the case of any default arising on the last day of
     a fiscal quarter occurring during the first three fiscal quarters of a
     fiscal year of Holdings) or 60 days (in the case of any default arising on
     the last day of the last fiscal quarter of any fiscal year of the
     Borrower)".

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          17.  Section 9 of the Credit Agreement is hereby further amended by
inserting the following new Section 9.10 immediately after Section 9.09
appearing in said Section:

          "9.10 CAPITAL CONTRIBUTION AGREEMENT. (i) The Capital Contribution
     Agreement or any material provision thereof shall cease to be in full force
     and effect except in accordance with the terms thereof, (ii) the Fund or
     any Person acting on behalf of the Fund shall deny or disaffirm its
     obligations under the Capital Contribution Agreement, (iii) the Fund or any
     Person acting on behalf of the Fund shall default in the due performance or
     observance of any term, covenant or agreement on its part to be performed
     or observed pursuant to the Capital Contribution Agreement or (iv) a
     Capital Contribution Event of Default under, and as defined in, the Capital
     Contribution Agreement shall occur;".

          18.  The definition of "Consolidated EBITDA" appearing in Section 10
of the Credit Agreement is hereby amended by inserting the following text
immediately after the second proviso appearing in said definition:

          "provided further that, for purposes of determining compliance with
     Sections 8.11, 8.12 and 8.13 and any determination pursuant to Section
     8.06(g), (x) if one or more Permitted Acquisitions is effected on or after
     the first day of the respective Test Period or Calculation Period and on or
     prior to the date of determination, Consolidated EBITDA shall be calculated
     on a PRO FORMA Basis after giving effect to such Permitted Acquisition and
     (y) if one or more Significant Asset Sales is effected on or after the
     first day of the respective Test Period or Calculation Period and on or
     prior to the date of determination, Consolidated EBITDA shall be calculated
     on a PRO FORMA Basis after giving effect to such Significant Asset Sale".

          19.  The definition of "Consolidated Net Income" appearing in Section
10 of the Credit Agreement is hereby amended by inserting the text "except for
determinations expressly required to be made on a PRO FORMA Basis," immediately
after the text "during such period, (ii)" appearing in said definition.

          20.  The definition of "Credit Document" appearing in Section 10 of
the Credit Agreement is hereby amended by inserting the text ", the Capital
Contribution Agreement" immediately after the text "the Subsidiary Guaranty"
appearing in said definition.

          21.  The definition of "Excess Cash Flow" appearing in Section 10 of
the Credit Agreement is hereby amended by deleting the text "and/or (i)"
appearing in said definition and inserting the text ", (i) and/or (j)" in lieu
thereof.

          22.  Section 10 of the Credit Agreement is hereby amended by (i)
deleting the definitions of "Applicable Base Rate Margin" and "Applicable
Eurodollar Margin" appearing in said Section and (ii) inserting the following
new definitions in appropriate alphabetical order in said Section:

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          "A TF Capital Call Percentage" shall mean, at any time of
     determination, a fraction (expressed as a percentage) the numerator which
     is equal to the aggregate principal amount of A Term Loans outstanding at
     such time and the denominator which is equal to the sum of (x) the
     aggregate principal amount of Term Loans outstanding at such time, (y) the
     aggregate principal amount of Swingline Loans and Revolving Loans
     outstanding at such time and (z) the aggregate amount of Letter of Credit
     Outstandings at such time.

          "Acquired EBITDA" shall mean, for any period, Consolidated EBITDA of
     the Person or business, division or product line being acquired pursuant to
     a Permitted Acquisition for such period (determined in accordance with the
     definition of Consolidated EBITDA contained herein, but treating references
     therein and in any other defined terms used in determining Consolidated
     EBITDA to "Holdings" to instead be references to the Person or business,
     division or product line being acquired pursuant to the respective
     Permitted Acquisition and without giving effect to clause (iv) of, and the
     provisos contained in, the definition of Consolidated EBITDA and to clauses
     (iv), (v), (vi), (vii) and (viii) of the definition of Consolidated Net
     Income used in determining Consolidated EBITDA).

          "Applicable Base Rate Margin" shall mean (i) in the case of A Term
     Loans, Revolving Loans and Swingline Loans, 2.50% LESS the Margin Reduction
     Discount, if any and (ii) in the B Term Loans, 3.00%.

          "Applicable Eurodollar Margin" shall mean (i) in the case of A Term
     Loans, Revolving Loans and Swingline Loans, 3.50% less the Margin Reduction
     Discount, if any and (ii) in the B Term Loans, 4.00%.

          "B TF Capital Call Percentage" shall mean, at any time of
     determination, a fraction (expressed as a percentage) the numerator which
     is equal to the aggregate principal amount of B Term Loans outstanding at
     such time and the denominator which is equal to the sum of (x) the
     aggregate principal amount of Term Loans outstanding at such time, (y) the
     aggregate principal amount of Swingline Loans and Revolving Loans
     outstanding at such time and (z) the aggregate amount of Letter of Credit
     Outstandings at such time.

          "Calculation Period" shall have the meaning provided in Section
     8.06(g).

          "Capital Call Contribution" shall have the meaning provided in Section
     8.16.

          "Capital Call Contribution Amount" shall mean, with respect to any
     Capital Call Contribution, an amount equal to the sum of (i) the aggregate
     amount of all cash contributed to the Borrower (via Holdings) pursuant to
     such Capital Call Contribution and (ii) the aggregate principal amount of
     all Senior Subordinated Notes contributed to the Borrower (via Holdings)
     pursuant to such Capital Call Contribution.

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          "Capital Contribution Agreement" shall mean that certain Capital
     Contribution and Support Agreement, dated as of March 30, 2001, among the
     Administrative Agent, Holdings, the Borrower and Cypress Merchant Banking
     Partners L.P. in the form of Exhibit N hereto, as the same may be amended,
     modified and/or supplemented from time to time in accordance with the terms
     hereof and thereof.

          "Fund" shall mean Cypress Merchant Bank Partners, L.P., a Delaware
     limited partnership, and/or Cypress Offshore Partners L.P., a Cayman Island
     limited partnership.

          "Interest Coverage Ratio" shall mean, as to any Person, for any
     period, the ratio of Consolidated EBITDA of such Person to Consolidated
     Cash Interest Expense of such Person for such period.

          "PRO FORMA Basis" shall mean, in connection with any calculation of
     compliance with any financial covenant or financial term, the calculation
     thereof after giving effect on a pro forma basis to (w) the incurrence of
     any Indebtedness (other than revolving Indebtedness, except to the extent
     same is incurred to refinance other outstanding Indebtedness or to finance
     Permitted Acquisitions) after the first day of the relevant Calculation
     Period or Test Period as if such Indebtedness had been incurred or issued
     (and the proceeds thereof applied) on the first day of the relevant
     Calculation Period or Test Period, (x) the permanent repayment or
     retirement of any Indebtedness (other than revolving Indebtedness, except
     to the extent accompanied by a permanent commitment reduction) after the
     first day of the relevant Calculation Period or Test Period as if such
     Indebtedness had been retired or redeemed on the first day of the relevant
     Calculation Period or Test Period, (y) the consummation of any Significant
     Asset Sale after the first day of the relevant Calculation Period or Test
     Period as if such Significant Asset Sale had been consummated on the first
     day of the relevant Calculation Period or Test Period and (z) the Permitted
     Acquisition, if any, then being (or proposed to be) consummated as well as
     any other Permitted Acquisition consummated after the first day of the
     relevant Calculation Period or Test Period and on or prior to the date of
     the respective Permitted Acquisition then being (or proposed to be)
     effected, with the following rules to apply in connection therewith:

          (i)  all Indebtedness (x) (other than revolving Indebtedness, except
     to the extent same is incurred to refinance other outstanding Indebtedness
     or to finance Permitted Acquisitions) incurred or issued after the first
     day of the relevant Calculation Period or Test Period (whether incurred to
     finance a Permitted Acquisition, to refinance Indebtedness or otherwise)
     shall be deemed to have been incurred or issued (and the proceeds thereof
     applied) on the first day of the respective Calculation Period or Test
     Period and remain outstanding through the date of determination and (y)
     (other than revolving Indebtedness, except to the extent accompanied by a
     permanent commitment reduction) permanently retired or redeemed after the
     first day of the relevant Calculation Period or Test Period shall be deemed
     to have been retired or redeemed on the first day of the respective
     Calculation Period or Test Period and remain retired through the date of
     determination;

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          (ii) all Indebtedness assumed to be outstanding pursuant to preceding
     clause (i) shall be deemed to have borne interest at (x) the rate
     applicable thereto, in the case of fixed rate indebtedness or (y) the rates
     which would have been applicable thereto during the respective period when
     same was deemed outstanding, in the case of floating rate Indebtedness
     (although interest expense with respect to any Indebtedness for periods
     while same was actually outstanding during the respective period shall be
     calculated using the actual rates applicable thereto while same was
     actually outstanding);

          (iii) in making any determination of Consolidated EBITDA on a PRO
     FORMA Basis, so long as the Acquired EBITDA of the Person or business,
     division or product line being acquired pursuant to the respective
     Permitted Acquisition has been audited for the entire Calculation Period by
     any of the "big six" accounting firms or another accounting firm acceptable
     to the Agent, PRO FORMA effect shall be given to any Permitted Acquisition
     effected during the respective Calculation Period or Test Period (or
     thereafter for purposes of Section 8.06(g)) (and such Acquired EBITDA shall
     be included in the calculation of Consolidated EBITDA) as if such Permitted
     Acquisition had occurred on the first day of the respective Calculation
     Period or Test Period, as the case may be, and taking into account
     factually supportable and identifiable cost savings and expenses which
     would otherwise be accounted for as an adjustment pursuant to Article 11 of
     Regulation S-X under the Securities Act, as if such cost savings or
     expenses were realized on the first day of the respective period; and

          (iv) in making any determination of Consolidated EBITDA on a PRO FORMA
     Basis, PRO FORMA effect shall be given to any Significant Asset Sale
     effected during the respective Calculation Period or Test Period (or
     thereafter for purposes of Section 8.06(g)) as if same had occurred on the
     first day of the respective Calculation Period or Test Period, as the case
     may be.

     Notwithstanding anything to the contrary contained above, (x) for purposes
     of Sections 8.11, 8.12 and 8.13 PRO FORMA effect (as otherwise provided
     above) shall only be given for events or occurrences which occurred during
     the respective Test Period but not thereafter and (y) for purposes of
     Section 8.02 PRO FORMA effect (as otherwise provided above) shall be given
     for events or occurrences which occurred during the respective Calculation
     Period and thereafter but on or prior to the respective date of
     determination.

          "Revolving Capital Call Percentage" shall mean, at any time of
     determination, a fraction (expressed as a percentage) the numerator which
     is equal to the sum of (i) the aggregate principal amount of Swingline
     Loans and Revolving Loans outstanding at such time plus (ii) the aggregate
     amount of Letter of Credit Outstandings at such time and the denominator
     which is equal to the sum of (x) the aggregate principal amount of Term
     Loans outstanding at such time, (y) the aggregate principal amount of
     Swingline Loans and Revolving Loans outstanding at such time and (z) the
     aggregate amount of Letter of Credit Outstandings at such time.

          "Significant Asset Sale" shall mean and include (i) any sale or
     disposition of any business or asset constituting an Asset Sale, the
     "enterprise value" of which business or

                                      -11-
   12

     asset (I.E., the aggregate of (x) the Net Cash Proceeds received by the
     Borrower and its Subsidiaries from the sale or disposition of such business
     or asset and (y) the aggregate amount of Indebtedness assigned to the buyer
     in connection with such sale or disposition) equals or exceeds $500,000 and
     (ii) that certain sale of assets of the Borrower and its Subsidiaries
     identified to the Administrative Agent on March 30, 2001.

          23.  Section 12.07(a) of the Credit Agreement is hereby amended by
inserting the following proviso immediately after the proviso appearing in said
Section:

          "PROVIDED FURTHER, that to the extent expressly required pursuant to
     the provisions of this Agreement, certain calculations shall be made on a
     PRO FORMA Basis".

          24.  The Credit Agreement is hereby amended by adding Exhibit N
thereto in the form attached hereto as Exhibit N.


II.  MISCELLANEOUS PROVISIONS.

          1.   In order to induce the Banks to enter into this Amendment, each
of Holdings and the Borrower hereby represents and warrants that:

               (a)  no Default or Event of Default exists as of the Fifth
     Amendment Effective Date, after giving effect to this Amendment; and

               (b)  all of the representations and warranties contained in the
     Credit Agreement or the other Credit Documents are true and correct in all
     material respects on the Fifth Amendment Effective Date, both before and
     after giving effect to this Amendment, with the same effect as though such
     representations and warranties had been made on and as of the Fifth
     Amendment Effective Date (it being understood that any representation or
     warranty made as of a specific date shall be true and correct in all
     material respects as of such specific date).

          2.   This Amendment is limited as specified and shall not constitute a
modification, acceptance or waiver of any other provision of the Credit
Agreement or any other Credit Document.

          3.   This Amendment may be executed in any number of counterparts and
by the different parties hereto on separate counterparts, each of which
counterparts when executed and delivered shall be an original, but all of which
shall together constitute one and the same instrument. A complete set of
counterparts shall be lodged with the Borrower and the Administrative Agent.

          4.   THIS AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES
HEREUNDER SHALL BE CONSTRUED IN ACCORDANCE WITH AND GOVERNED BY THE LAW OF THE
STATE OF NEW YORK.

                                      -12-
   13

          5.   This Amendment shall become effective on the date (the "Fifth
Amendment Effective Date") when each of the following conditions shall have been
satisfied:

          (i)  Holdings, the Borrower and the Required Banks shall have signed a
     counterpart hereof (whether the same or different counterparts) and shall
     have delivered (including by way of facsimile transmission) the same to the
     Administrative Agent at its Notice Office;

          (ii) Cypress Merchant Banking Partners L.P., Holdings and the Borrower
     shall have duly authorized, executed and delivered the Capital Contribution
     Agreement in the form of Exhibit N to the Credit Agreement and the Capital
     Contribution Agreement shall be in full force and effect;

          (iii) the Borrower shall have paid to the Administrative Agent for
     distribution to each Bank that has executed a counterpart hereof on or
     prior to 5:00 P.M. (New York time) on March 30, 2001 an amendment fee equal
     to 0.25% of the sum of (x) its Revolving Commitment, if any, as in effect
     on the Fifth Amendment Effective Date (immediately after giving effect
     thereto and to the reduction of the Total Revolving Loan Commitment
     required pursuant to Section 3.03(d) of the Credit Agreement (as amended
     hereby) PLUS (y) the aggregate outstanding principal amount of its Term
     Loans, if any, immediately prior to the Fifth Amendment Effective Date;

          (iv) the Administrative Agent shall have received from Cypress
     Merchant Banking Partners L.P. certified copies of resolutions of its
     Management Committee with respect to the Capital Contribution Agreement and
     such resolutions shall be reasonably satisfactory to the Administrative
     Agent; and

          (v)  the Administrative Agent shall have received from Simpson,
     Thacher & Bartlett, special New York counsel to the Credit Parties and
     Cypress Merchant Banking Partners L.P., an opinion addressed to the
     Administrative Agent and each of the Lenders and dated the Fifth Amendment
     Effective Date in form and substance reasonably satisfactory to the
     Administrative Agent, and covering such matters incident to this Amendment
     as the Administrative Agent may reasonably request.

          6.   From and after the Fifth Amendment Effective Date, all references
in the Credit Agreement and each of the other Credit Documents to the Credit
Agreement shall be deemed to be references to the Credit Agreement as modified
hereby.

                                      * * *



                                      -13-
   14

     IN WITNESS WHEREOF, the parties hereto have caused their duly authorized
officers to execute and deliver this Amendment as of the date first above
written.


                                   AMTROL HOLDINGS, INC.


                                   By: /s/ David P. Spalding
                                      ------------------------------------------
                                      Name:
                                      Title:


                                   AMTROL INC.


                                   By: /s/ Larry T. Guillemette
                                      ------------------------------------------
                                      Name:
                                      Title:


                                   BANKERS TRUST COMPANY, Individually and as
                                        Administrative Agent


                                   By: /s/ Susan L. LeFevre
                                      ------------------------------------------
                                      Name:
                                      Title:


                                   MORGAN STANLEY SENIOR FUNDING, INC.,
                                        Individually and as Documentation Agent


                                   By: /s/ T. Morgan Edwards II
                                      ------------------------------------------
                                      Name:
                                      Title:



                                      -14-
   15

                                   BANKBOSTON, N.A.


                                   By:
                                      ------------------------------------------
                                      Name:
                                      Title:


                                   THE BANK OF NEW YORK


                                   By:
                                      ------------------------------------------
                                      Name:
                                      Title:


                                   THE BANK OF NOVA SCOTIA


                                   By:
                                      ------------------------------------------
                                      Name:
                                      Title:


                                   CITIZENS FINANCIAL GROUP INC


                                   By:
                                      ------------------------------------------
                                      Name:
                                      Title:


                                   FIRST SOURCE FINANCIAL LLP
                                        By First Source Financial Inc.,
                                        Its manager


                                   By:
                                      ------------------------------------------
                                      Name:
                                      Title:


                                      -15-
   16

                                   FLEET NATIONAL BANK


                                   By:
                                      ------------------------------------------
                                      Name:
                                      Title:


                                   SOCIETE GENERALE


                                   By: /s/ Cynthia A. Jay
                                      ------------------------------------------
                                      Name:
                                      Title:


                                   AMARA-1 FINANCE LTD.


                                   By: /s/ Gregory Stoeckle
                                      ------------------------------------------
                                      Name:
                                      Title:


                                      -16-
   17

                                   CERES FINANCE LTD.


                                   By: /s/ Gregory Stoeckle
                                      ------------------------------------------
                                      Name:
                                      Title:


                                   KZH PAMCO LLC


                                   By: /s/ Kimberly Rowe
                                      ------------------------------------------
                                      Name:
                                      Title:


                                   KATONAH I, LTD.


                                   By: /s/ Ralph Della Rocca
                                      ------------------------------------------
                                      Name:
                                      Title:


                                   KZH HIGHLAND - 2 LLC


                                   By: /s/ Kimberly Rowe
                                      ------------------------------------------
                                      Name:
                                      Title:


                                   AVALON CAPITAL LTD - 2

                                   By: Invesco Senior Secured Management, Inc.
                                       As Portfolio Advisor


                                   By: /s/ Gregory Stoeckle
                                      ------------------------------------------
                                      Name:
                                      Title:




                                      -17-