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                                                                  EXHIBIT 10.1.6

                     WAIVER AND CONSENT TO CREDIT AGREEMENT
                       AND CAPITAL CONTRIBUTION AGREEMENT



          WAIVER AND CONSENT TO CREDIT AGREEMENT AND CAPITAL CONTRIBUTION
AGREEMENT, dated as of November 5, 2001 (this "Waiver"), 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"),
BANKERS TRUST COMPANY, as Administrative Agent (in such capacity, the
"Administrative Agent"), and CYPRESS MERCHANT BANKING PARTNERS L.P. (the
"Fund"). 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");

          WHEREAS, the Fund, Holdings, the Borrower and the Administrative Agent
are parties to a Capital Contribution Agreement, dated as of March 30, 2001 (as
the same as in effect on the date hereof, "Capital Contribution Agreement"); and

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

          NOW, THEREFORE, it is agreed:


          1.   The Lenders hereby waive, during (and only during) the period
commencing on September 30, 2001 through and including December 26, 2001 (the
"Waiver Period"), compliance by Holdings with Section 8.12 of the Credit
Agreement as of (and only as of) the fiscal quarter of Holdings ended September
30, 2001 (the "Relevant Test Quarter"), it being understood and agreed that upon
the expiration of the Waiver Period, the failure of Holdings to comply with
Section 8.12 of the Credit Agreement as of the Relevant Test Quarter shall give
rise to an immediate Event of Default under Section 9.03 of the Credit
Agreement, subject, however, to any cure thereof resulting from the
recalculation of Holdings' Leverage Ratio as at September 30, 2001 as
contemplated by Section 2(II) of this Waiver below.

          2.   Notwithstanding anything to the contrary contained in the Capital
Contribution Agreement or Section 8.16 of the Credit Agreement, Holdings, the
Borrower, the Fund and the Banks hereby agree that (I) the Fund shall not be
required to make any Capital Contribution (as defined in the Capital
Contribution Agreement) which would (in the absence of

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this Waiver) have otherwise been required to be made by it pursuant to Section
2(a) of the Capital Contribution Agreement on the first Quarterly Financial
Statements Delivery Date (as defined in the Capital Contribution Agreement)
occurring after the fiscal quarter of Holdings ended September 30, 2001 (the
"Original Capital Contribution Date"), so long as (and only so long as) (i)
Holdings and/or the Fund shall have calculated the amount of the Capital
Contribution which would (in the absence of this Waiver) have been required to
have been made pursuant to the Capital Contribution Agreement on the Original
Capital Contribution Date and delivered such calculations (set forth in
reasonable detail) to the Administrative Agent on the Original Capital
Contribution Date and (ii) the Fund shall have made on December 27, 2001 any
Capital Contribution which would (in the absence of this Waiver) have been
required to have been made by it on the Original Capital Contribution Date in
the amount specified pursuant to preceding subclause (i) and otherwise in
accordance with the requirements of the Capital Contribution Agreement, (II)
immediately after giving effect to the Capital Contribution described in
preceding clause (I)(ii), Holdings' Leverage Ratio as of September 30, 2001
shall be recalculated on December 27, 2001 in accordance with the requirements
of Section 8.16 of the Credit Agreement (on the same basis as if such
calculation had been made on the Original Capital Contribution Date in
accordance with the requirements of said Section 8.16), (III) any Capital
Contribution made as required by preceding clause (I)(ii) shall be a "Capital
Contribution" for all purposes of the Capital Contribution Agreement and a
"Capital Call Contribution" for all purposes of the Credit Agreement and (IV)
any failure on the part of the Fund to comply with its obligations described in
preceding clause (I)(ii) shall constitute an Event of Default for all purposes
of the Credit Agreement and the other Credit Documents.

          3.   The Fund, for its part, by its acceptance of this Waiver, agrees
to make any Capital Contribution required to be made by it pursuant to Section
2(I)(ii) above.

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

               (a)  no Default or Event of Default exists as of the Waiver
     Effective Date, after giving effect to this Waiver; 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 Waiver Effective Date, both before and after
     giving effect to this Waiver, with the same effect as though such
     representations and warranties had been made on and as of the Waiver
     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).

          5.   This Waiver 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.

          6.   This Waiver 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


                                      -2-

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instrument. A complete set of counterparts shall be lodged with the Borrower and
the Administrative Agent.

          7.   THIS WAIVER 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.

          8.   This Waiver shall become effective on the date (the "Waiver
Effective Date") when 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.

          9.   From and after the Waiver 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.

          10.  The Borrower hereby covenants and agrees that, so long as the
Waiver Effective Date occurs, it shall pay (in U.S. Dollars) to each Bank which
executes and delivers to the Administrative Agent (or its designee) a
counterpart hereof by the later to occur of (x) the close of business on the
Waiver Effective Date or (y) 5:00 p.m. (New York City time) on Tuesday, November
13, 2001 (such letter date, the "Outside Date"), a non-refundable cash fee (the
"Consent Fee") in an amount equal to 10 basis points (0.10%) of an amount equal
to the sum of (i) the aggregate principal amount of all Term Loans made by such
Bank and outstanding on the Waiver Effective Date and (ii) the Revolving
Commitment of such Bank as in effect on the Waiver Effective Date, which Consent
Fee shall not be subject to counterclaim or set-off, or be otherwise affected
by, any claim or dispute relating to any other matter and shall be paid by the
Borrower to the Administrative Agent for distribution to the Banks not later
than the second Business Day following the Outside Date.


                                      * * *


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


                                    AMTROL HOLDINGS, INC.



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



                                    AMTROL INC.



                                    By: /s/ Larry T. Guillemette
                                        ----------------------------------------
                                        Name: Larry T. Guillemette
                                        Title: Executive Vice President
                                               Chief Financial Officer



                                    CYPRESS MERCHANT BANKING PARTNERS, L.P.



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



                                    BANKERS TRUST COMPANY, Individually and as
                                        Administrative Agent



                                    By: /s/ Gregory Shemn
                                        ----------------------------------------
                                        Name: Gregory Shemn
                                        Title: Director



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


                                    By: /s/ Stephen Hannan
                                        ----------------------------------------
                                        Name: Stephen Hannan
                                        Title: Vice President



                                      -4-


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                                     THE BANK OF NOVA SCOTIA



                                     By: /s/ M. R. Bradley
                                         ---------------------------------------
                                         Name: M. R. Bradley
                                         Title: Authorized Signatory



                                     CITIZENS FINANCIAL GROUP INC



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



                                     FLEET NATIONAL BANK



                                     By: /s/ Albert J. Buresh
                                         ---------------------------------------
                                         Name: Albert J. Buresh
                                         Title: Vice President



                                     SOCIETE GENERALE



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




                                      -5-

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                                    AMARA-1 FINANCE LTD.



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



                                    CERES FINANCE LTD.
                                    By: INVESCO Senior Secured Management, Inc.,
                                     as Sub-Managing Agent



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



                                    KZH HIGHLAND-2 LLC



                                    By: /s/ Susan Lee
                                        ----------------------------------------
                                        Name: Susan Lee
                                        Title: Authorized Agent



                                    KZH PAMCO LLC



                                    By: /s/ Susan Lee
                                        ----------------------------------------
                                        Name: Susan Lee
                                        Title: Authorized Agent



                                    AVALON CAPITAL LTD. 2
                                    By: INVESCO Senior Secured Management, Inc.,
                                     as Portfolio Advisor



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



                                      -6-


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                                       GENERAL ELECTRIC CAPITAL CORPORATION



                                       By: /s/ Scott Michael Galletti
                                           -------------------------------------
                                           Name: Scott Michael Galletti
                                           Title: Duly Authorized Signatory



                                       KATONAH I, LTD.



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




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