<PAGE>   1


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

                                    FORM 10-Q

                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

For the quarterly period ended: October 3, 1998    
                                ---------------

Commission file number:             0-20328
                                ---------------


                                   AMTROL INC.
             (exact name of registrant as specified in its charter)

         Rhode Island                                      05-0246955
         ------------                                      ----------


                 1400 Division Road, West Warwick, RI 02893-1008
                 -----------------------------------------------
                    (Address of principal executive offices)

Registrant's telephone number, including area code: (401) 884-6300
                                                    --------------


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.


                           Yes [X]           No [ ]


Indicate the number of shares outstanding of each of the issuer's classes of
common stock, as of the latest practicable date.


                    100 Shares of Common Stock $.01 Par Value
                    -----------------------------------------
                              as of October 3, 1998


<PAGE>   2

AMTROL INC. AND SUBSIDIARIES
--------------------------------------------------------------------------------


                 FORM 10-Q FOR THE QUARTER ENDED OCTOBER 3, 1998


                                      INDEX

                                                                            PAGE
                                                                            ----

PART I.         FINANCIAL INFORMATION

     Item 1.    Consolidated Balance Sheets -
                    October 3, 1998 and December 31, 1997                     2

                Consolidated Statements of Operations -
                    For the Quarter and Nine Months Ended 
                    October 3, 1998 and October 4, 1997                       3

                Consolidated Statement of Shareholders' Equity -
                    For the Nine Months Ended October 3, 1998                 4

                Consolidated Statements of Cash Flows -
                    For the Nine Months Ended October 3, 1998
                    and October 4, 1997                                       5

                Notes to Consolidated Financial Statements                    6

     Item 2.    Management's Discussion and Analysis of Results of
                    Operations and Financial Condition                       11

PART II.        OTHER INFORMATION

     Item 6.    Exhibits and Reports  on Form 8-K                            20

                Signatures                                                   21


                                       1
<PAGE>   3



                          AMTROL INC. AND SUBSIDIARIES

                           CONSOLIDATED BALANCE SHEETS
                           (UNAUDITED - IN THOUSANDS)

                                     ASSETS

<TABLE>
<CAPTION>
                                                                          OCTOBER 3,       DECEMBER 31,
                                                                             1998              1997
                                                                          ----------       ------------
<S>                                                                        <C>               <C>     
CURRENT ASSETS:
        Cash and cash equivalents                                          $    506          $    544
        Accounts receivable, less allowance for doubtful accounts            39,425            30,180
        Inventories                                                          28,720            31,285
        Prepaid income taxes                                                  2,455             2,495
        Prepaid expenses and other                                            2,746             1,412
        Assets held for sale                                                    489             1,533
                                                                           --------          --------
           Total current assets                                              74,341            67,449
                                                                           --------          --------

PROPERTY, PLANT AND EQUIPMENT, NET                                           52,156            45,687

OTHER ASSETS:
        Goodwill                                                            174,863           169,784
        Financing costs                                                       7,025             7,762
        Deferred income taxes                                                 3,611               419
        Other                                                                   739             1,899
                                                                           --------          --------
                                                                            186,238           179,864
                                                                           --------          --------
                                                                           $312,735          $293,000
                                                                           ========          ========


                      LIABILITIES AND SHAREHOLDERS' EQUITY

CURRENT LIABILITIES
        Current maturities of long-term debt                               $  1,984          $  3,498
        Notes payable to banks                                                8,401             4,397
        Accounts payable                                                     25,912            15,718
        Accrued expenses                                                     15,489            15,779
        Accrued interest                                                      4,199               608
        Accrued income taxes                                                    879             3,073
                                                                           --------          --------
           Total current liabilities                                         56,864            43,073
                                                                           --------          --------

LONG TERM DEBT, LESS CURRENT MATURITIES                                     177,817           184,164

OTHER NONCURRENT LIABILITIES                                                  9,005             6,659

SHAREHOLDERS' EQUITY
        Capital stock $.01 par value - authorized 1,000 shares,
           100 shares issued                                                      -                 -
        Additional paid-in capital                                           89,823            69,326
        Retained deficit                                                    (21,837)           (9,937)
        Accumulated other comprehensive gain (loss)                           1,063              (285)
                                                                           --------          --------
           Total shareholders' equity                                        69,049            59,104
                                                                           --------          --------
                                                                           $312,735          $293,000
                                                                           ========          ========
</TABLE>



  The accompanying notes are an integral part of these consolidated financial
                                  statements.

                                       2


<PAGE>   4


                          AMTROL INC. AND SUBSIDIARIES

                      CONSOLIDATED STATEMENTS OF OPERATIONS
                           (UNAUDITED - IN THOUSANDS)



<TABLE>
<CAPTION>
                                                       QUARTER ENDED               NINE MONTHS ENDED
                                                 -------------------------     --------------------------
                                                 OCTOBER 3,     OCTOBER 4,     OCTOBER 3,      OCTOBER 4,
                                                   1998           1997           1998             1997
                                                  -------        -------        --------        --------

<S>                                               <C>            <C>            <C>             <C>     
NET SALES                                         $55,573        $48,166        $154,924        $136,711

Cost of goods sold                                 43,820         35,905         120,849         101,788
Provision for abnormal warranty costs                   -              -           4,500               -
                                                  -------        -------        --------        --------
TOTAL COST OF GOODS SOLD                           43,820         35,905         125,349         101,788

          GROSS PROFIT                             11,753         12,261          29,575          34,923

OPERATING EXPENSES
Selling, general and
     administrative                                 6,442          6,648          19,806          19,323
Plant closing and
     reorganization costs                               -          2,500           4,450           2,500
Management restructuring                              671              -           4,171               -
Amortization of goodwill                            1,136          1,035           3,348           2,910
                                                  -------        -------        --------        --------
          Income (loss) from operations             3,504          2,078          (2,200)         10,190

OTHER INCOME (EXPENSE):
Interest expense                                   (5,289)        (4,949)        (15,755)        (13,896)
Interest income                                        43             55             117             345
License and distributorship fees                       72             80             170             190
Other, net                                            172            297             696             286
                                                  -------        -------        --------        --------
          Loss before (benefit)
            provision for income taxes             (1,498)        (2,439)        (16,972)         (2,885)

(BENEFIT) PROVISION FOR
     INCOME TAXES                                    (110)           456          (5,072)          1,253
                                                  -------        -------        --------        --------
          NET LOSS                                $(1,388)       $(2,895)       $(11,900)       $ (4,138)
                                                  =======        =======        ========        ========
</TABLE>






   The accompanying notes are an integral part of these consolidated financial
                                  statements.

                                       3


<PAGE>   5
                          AMTROL INC. AND SUBSIDIARIES

                 CONSOLIDATED STATEMENT OF SHAREHOLDERS' EQUITY
                           (UNAUDITED - IN THOUSANDS)


<TABLE>
<CAPTION>
                                                                                         ACCUMULATED
                                                           ADDITIONAL                       OTHER
                                               CAPITAL      PAID - IN      RETAINED     COMPREHENSIVE
                                                STOCK        CAPITAL        DEFICIT      GAIN (LOSS)
                                               -------     ----------      --------     -------------
<S>                                              <C>        <C>            <C>              <C>    
BALANCE, December 31, 1997                         -        $69,326        $ (9,937)        $ (285)
      Capital Contribution                                   20,497
      Net Loss                                     -              -         (11,900)             -
      Currency Translation Adjustment              -              -               -          1,348
                                                 ---        -------        --------         ------
BALANCE, October 3, 1998                           -        $89,823        $(21,837)        $1,063
                                                 ===        =======        ========         ======
</TABLE>













   The accompanying notes are an integral part of these consolidated financial
                                  statements.

                                        4
<PAGE>   6

                          AMTROL INC. AND SUBSIDIARIES

                      CONSOLIDATED STATEMENTS OF CASH FLOWS
                           (UNAUDITED - IN THOUSANDS)

<TABLE>
<CAPTION>
                                                                                 NINE MONTHS ENDED
                                                                             --------------------------
                                                                             OCTOBER 3,      OCTOBER 4,
                                                                                1998            1997
                                                                             ----------      ----------

<S>                                                                           <C>             <C>      
CASH FLOWS FROM OPERATING ACTIVITIES:
    Net Loss                                                                  $(11,900)       $ (4,138)
    Adjustments to reconcile net loss to net cash provided by
    operating activities -
        Depreciation and amortization                                            9,399           8,176
        Provision for losses on accounts receivable                                177             207
        Loss on sale of fixed assets                                                 -               2
        Non-cash charges                                                        11,600               -

    Changes in operating assets and liabilities                                 (9,069)          1,178
                                                                              --------        --------

            Net cash provided by operating activities                              207           5,425

CASH FLOWS FROM INVESTING ACTIVITIES:
    Acquisition of NOVA, net of cash acquired                                   (5,855)              -
    Acquisition of Alfa, net of cash acquired                                        -         (25,500)
    Proceeds from sale of assets held for sale                                   2,025             681
    Capital expenditures                                                        (9,358)         (6,061)
                                                                              --------        --------

            Net cash used in investing activities                              (13,188)        (30,880)

CASH FLOWS FROM FINANCING ACTIVITIES:
    Repayment of debt                                                          (43,048)         (1,292)
    Issuance of debt                                                            35,486          20,000
    Capital Contribution                                                        20,497               -
    Deferred installment finance and acquisition costs                               -           7,000
                                                                              --------        --------

            Net cash provided by financing activities                           12,935          25,708
                                                                              --------        --------

NET (DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS                               (46)            253

Effect of exchange rate changes on cash and cash equivalents                         8               -

CASH AND CASH EQUIVALENTS, beginning of period                                     544           6,383
                                                                              --------        --------

CASH AND CASH EQUIVALENTS, end of period                                      $    506        $  6,636
                                                                              ========        ========
</TABLE>






   The accompanying notes are an integral part of these consolidated financial
                                  statements.

                                       5
<PAGE>   7



AMTROL INC. AND SUBSIDIARIES
--------------------------------------------------------------------------------

                   NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
                                  (UNAUDITED)

1.       BASIS OF PRESENTATION 

         In the opinion of management, the accompanying unaudited consolidated
         financial statements contain all adjustments necessary to present
         fairly, in accordance with generally accepted accounting principles,
         the Company's financial position, results of operations and cash flows
         for the interim periods presented. Such adjustments consisted of only
         normal recurring items. The results of operations for the interim
         periods shown in this report are not necessarily indicative of results
         for any future interim period or for the entire year. These
         consolidated financial statements do not include all disclosures
         associated with annual financial statements and accordingly should be
         read in conjunction with the consolidated financial statements and
         notes thereto included in the Company's Annual Report on Form 10-K.

2.       USE OF ESTIMATES

         The preparation of financial statements in conformity with generally
         accepted accounting principles requires management to make estimates
         and assumptions that affect the reported amounts of assets and
         liabilities and disclosure of contingent assets and liabilities at the
         date of the financial statements and the reported amounts of revenues
         and expenses during the reporting period. Actual results could differ
         from those estimates.

3.       SIGNIFICANT ACCOUNTING POLICIES

         GOODWILL

         Goodwill represents the excess of purchase price over the fair value of
         net assets acquired in connection with the 1996 acquisition of the
         Company by affiliates of the Cypress Group L.L.C. (approximately $145
         million), the 1997 acquisition of Petroleo Mecanica Alfa, S.A. ("Alfa")
         (approximately $23 million) and the 1998 acquisition of NOVA
         Wassererwarmer GmbH ("NOVA") (approximately $7 million) and is included
         in other assets. Goodwill is being amortized up to 40 years.

         DEFERRED FINANCING COSTS

         Deferred financing costs are stated at cost as a component of other
         assets and are amortized over the life of the related debt using the
         effective interest method. Amortization of deferred financing costs is
         included in interest expense.


                                       6
<PAGE>   8


AMTROL INC. AND SUBSIDIARIES
--------------------------------------------------------------------------------

                NOTES TO CONSOLIDATED FINANCIAL STATEMENTS-CONT.
                                   (UNAUDITED)

4.       INVENTORIES

         Inventories are stated at the lower of cost or market and were as
         follows:

                                            OCTOBER 3, 1998    DECEMBER 31, 1997
                                            ---------------    -----------------
                                                       (in thousands)

         Raw Materials and Work in Process       $18,421            $13,670
         Finished Goods                           10,299             17,615
                                                 -------            -------
                                                 $28,720            $31,285
                                                 =======            =======

         Inventories valued under the last-in, first-out (LIFO) cost method
         comprised approximately 44.0% of the October 3, 1998 totals and 68.2%
         of the December 31, 1997 totals.

5.       LONG-TERM DEBT AND NOTES PAYABLE TO BANKS

         The Bank Credit Agreement (the "Agreement") between the Company and a
         syndicate of lenders provides for secured borrowings consisting of (i)
         a five and one-half year revolving credit facility providing for up to
         $30 million in revolving loans, $5.0 million of which may be used for
         letters of credit (the "Revolving Credit Facility") and (ii) a term
         loan facility consisting of a five and one-half year Tranche A Term
         Loan and a seven and one-half year Tranche B Term Loan (collectively,
         the Term Loans). In addition, the Company has issued $115.0 million of
         Senior Subordinated Notes due in 2006 (the "Notes"). The Notes are
         unsecured obligations of the Company. The Notes bear interest at a rate
         of 10.625% per annum, which is payable semi-annually on each June 30
         and December 31.

         On July 31, 1998, the Company amended the Agreement to allow for an
         early repayment of a portion of the principal outstanding and to modify
         certain loan agreement covenants to be more in line with the Company's
         business plans. In connection with this amendment, the Company repaid
         borrowings of $20.5 million.

         Under the terms of the Agreement, as amended on July 31, AMTROL is
         required to comply, and is in compliance, with certain financial
         covenants and restrictions as of October 3, 1998.

6.       SHAREHOLDERS' EQUITY

         On July 31, 1998, the Cypress Group L.L.C. and members of senior
         management contributed an additional $20.5 million of new equity into
         the Company's parent, AMTROL Holdings Inc. In turn, AMTROL Holdings
         Inc. contributed a like amount to the Company. The additional capital
         contribution primarily was used to pay down Revolving Loans and
         outstanding Term A Loans under the Credit Agreement.



                                       7



<PAGE>   9
AMTROL INC. AND SUBSIDIARIES
--------------------------------------------------------------------------------

                NOTES TO CONSOLIDATED FINANCIAL STATEMENTS-CONT.
                                   (UNAUDITED)


7.       PLANT CLOSINGS, REORGANIZATION AND RESTRUCTURING CHARGES

         The Company closed its Nashville, Tennessee production facility in
         December 1997 and transferred certain production lines to its West
         Warwick, Rhode Island facility. Costs involved in closing the Nashville
         facility and starting production in West Warwick have been higher than
         anticipated due to unexpected retrofitting and reconditioning required
         for the relocated equipment, damage to equipment during shipment, and
         delays in preparing the Nashville building for sale. During the second
         quarter of 1998, the Company recorded charges relating to the
         incremental costs associated with the Nashville closure and production
         relocation approximating $6.0 million (including $1.5 million of
         production inefficiencies included in cost of goods sold). An
         additional $1.1 million of production inefficiencies was included in
         cost of goods sold in the third quarter. In addition, the Company
         recorded management restructuring charges of $4.2 million, including
         $0.7 million recorded in the third quarter, in connection with the
         discontinuation and reduction of certain product lines and a
         reorganization of its management group.

         The Company has been experiencing an unusually high level of warranty
         claims for a particular product relating to a 1995-1996 manufacturing
         problem which has since been corrected. Actions taken by the Company 
         to mitigate the level of returns for products manufactured during that
         time period have not reduced the return rate to the extent expected.
         Accordingly, the Company recorded an additional loss provision in the
         second quarter of $4.5 million for abnormal warranty costs relating to
         this product.

         In September 1997, the Company ceased operations at its Singapore
         facility. The Company relocated its production of non-returnable
         chemical containers to the Alfa facility in Guimaraes, Portugal. In
         connection with the closure, the Company recorded a pre-tax charge to
         operating expenses of $2.5 million in the third quarter.

8.       PROVISION FOR INCOME TAXES

         The effective income tax rates used in the interim financial statements
         are estimates of the full year's rates. The difference for 1998 between
         the provision computed using the statutory U.S. federal income tax rate
         and the provision for income taxes in the accompanying consolidated
         financial statements is primarily the result of goodwill amortization.



                                       8
<PAGE>   10


AMTROL INC. AND SUBSIDIARIES
--------------------------------------------------------------------------------

                NOTES TO CONSOLIDATED FINANCIAL STATEMENTS-CONT.
                                   (UNAUDITED)

9.       COMPREHENSIVE INCOME

         As of January 1, 1998, the Company adopted Statement of Financial
         Accounting Standards No. 130, Reporting Comprehensive Income. Statement
         130 establishes new rules for the reporting and display of
         comprehensive income and its components. The adoption of this Statement
         had no impact on the Company's net loss or shareholders' equity.
         Statement 130 requires certain items which previously had been reported
         separately in shareholders' equity to be included in other
         comprehensive income. For the Company, the only such item was the
         foreign currency cumulative translation adjustment. Prior year
         financial statements have been reclassified to conform to the
         requirements of Statement 130. The total comprehensive gain (loss),
         which is comprised of the net loss and the foreign currency translation
         adjustment, was as follows: 
  

<TABLE>
<CAPTION>
                                              QUARTER ENDED           NINE MONTHS ENDED
                                           --------------------    -----------------------
                                           OCTOBER 3  OCTOBER 4    OCTOBER 3     OCTOBER 4
                                             1998       1997         1998          1997
                                           ---------  ---------    ---------     ---------
         <S>                                 <C>     <C>           <C>           <C>

         Total Comprehensive Gain (Loss)     $230    $(2,895)      $(10,552)     $(4,138)

</TABLE>
                               
10.      SALE OF ASSETS

         In May 1997, the Company sold all of the assets of its American Granby
         Inc. subsidiary. Accordingly, the results of American Granby are
         included in the accompanying consolidated statements of operations for
         the first five months of 1997. For the nine month period ended October
         4, 1997, American Granby generated net sales of $7.6 million but did
         not generate any operating income. Also in May 1997, the Company sold
         its Peru, Indiana production facility and the related pump business.
         AMTROL transferred certain production activities performed in Peru to
         the Company's West Warwick, RI facility.

11.      ACQUISITIONS

         On June 9, 1998, the Company acquired NOVA Wassererwarmer GmbH ("NOVA")
         located in Donaueschingen, Germany for approximately $6.0 million
         (United States Dollars) plus assumed debt of $2.0 million. NOVA
         manufactures high-end residential and commercial water heaters which
         are marketed primarily in Germany, Switzerland and Austria. This
         acquisition provides AMTROL with expanded manufacturing and
         distribution capabilities in central Europe, in addition to the
         opportunity to offer many of AMTROL's complementary hydronic heating
         and water systems products in the European market. AMTROL assumed
         immediate management control of NOVA and, accordingly, the operating
         results and financial position of NOVA are included in the consolidated
         results of operations and consolidated balance sheets of AMTROL from
         the acquisition date.



                                       9



<PAGE>   11
AMTROL INC. AND SUBSIDIARIES
--------------------------------------------------------------------------------

                NOTES TO CONSOLIDATED FINANCIAL STATEMENTS-CONT.
                                   (UNAUDITED)


         On June 30, 1997, the Company acquired all the outstanding capital
         shares of Petroleo Mecanica Alfa, S.A. ("Alfa"), a corporation
         organized under the laws of Portugal, for $25.5 million (United States
         Dollars) plus assumed debt of $8.7 million (the "Acquisition"). Alfa is
         a leading designer and manufacturer of reusable steel cylinders used
         for the storage and transportation of heating and refrigerant gases and
         maintains a production facility in Guimaraes, Portugal. Alfa provides
         AMTROL with a significant low cost manufacturing base from which to
         serve Europe and the Far East. AMTROL assumed immediate management
         control of Alfa and, accordingly, the operating results and financial
         position of Alfa are included in the consolidated results of operations
         and consolidated balance sheets of AMTROL from July 1, 1997.

         The combined operating results of Alfa and NOVA included in third
         quarter and year-to-date 1998 operating results in the accompanying
         consolidated statement of operations are as follows in millions:

                                                        NET       OPERATING
                                                       SALES        INCOME
                                                       -----      ---------
      
               Quarter ended October 3, 1998           $16.6         $0.9
               Nine months ended October 3, 1998       $42.0         $4.0




                                       10
<PAGE>   12



AMTROL INC. AND SUBSIDIARIES
--------------------------------------------------------------------------------


ITEM 2.

                     MANAGEMENT'S DISCUSSION AND ANALYSIS OF
                  RESULTS OF OPERATIONS AND FINANCIAL CONDITION


OVERVIEW

The following discussion should be read in conjunction with the consolidated
Financial Statements and Notes thereto appearing elsewhere in this report. This
report contains forward-looking statements within the meaning of Section 27A of
the Securities Act of 1933 and Section 21E of the Securities Exchange Act of
1934. Such statements involve risks and uncertainties that could cause actual
results to differ materially from those set forth in such forward-looking
statements. Among other things, expectations for upcoming periods are based on
assumptions which management believes to be reasonable at this time, including
assumptions concerning the volume and product mix of sales. Moreover, there can
be no assurances when initiatives undertaken by the Company to rationalize its
manufacturing operations and improve plant productivity will be successful.
Other significant potential risks and uncertainties include the following: risks
associated with indebtedness; uncertainties of its acquisition strategy,
including the successful integration of the NOVA and Alfa Acquisitions; high
level of competition in the Company's markets; importance and costs of product
innovation; risks associated with international operations; product liability
exposure and the risk of adverse effects of economic and regulatory conditions
on sales; and risks associated with environmental matters.

PLAN OF RESTRUCTURING AND REORGANIZATION

During the second quarter of 1998, the Company adopted a plan of restructuring
and reorganization (the "Plan") to address several adverse developments in its
North American operations. The Plan addresses necessary changes in the Company's
West Warwick, Rhode Island facility to improve the productivity of the
production lines transferred from its Nashville, Tennessee facility in 1997,
discontinuance of certain product lines and recognition of the resulting decline
in inventory value for the products impacted, and replacement of certain senior
executives and others on the management team. The Company also determined that
mitigating actions intended to reduce the level of warranty returns associated
with a 1995/1996 manufacturing problem have not reduced warranty claims relating
to this product to the extent expected and that an additional warranty provision
is required. Costs associated with the Plan, manufacturing inefficiencies
related to the relocated production lines, and the additional warranty provision
aggregate $16.3 million and have been reflected in the accompanying financial
statements, including $1.8 million recorded in the third quarter.





                                       11


<PAGE>   13
AMTROL INC. AND SUBSIDIARIES
--------------------------------------------------------------------------------

                     MANAGEMENT'S DISCUSSION AND ANALYSIS OF
                  RESULTS OF OPERATIONS AND FINANCIAL CONDITION


RESULTS OF OPERATIONS

The following table sets forth, for the periods indicated, the percentages of
the Company's net sales represented by certain income and expense items in the
Company's Consolidated Statements of Operations.


<TABLE>
<CAPTION>
                                                    QUARTER ENDED                NINE MONTHS ENDED
                                              ------------------------       -------------------------
                                              OCTOBER 3,    OCTOBER 4,       OCTOBER 3,     OCTOBER 4, 
                                                1998          1997              1998           1997
                                              ----------    ----------       ----------     ----------
<S>                                              <C>           <C>              <C>            <C>   
Net Sales                                        100.0%        100.0%           100.0%         100.0%
Cost of Goods Sold                               78.9           74.5             78.0           74.5
Provision for Abnormal Warranty Costs               -              -              2.9              -
                                                 -----         ------           ------         ------
Total Cost of Goods Sold                         78.9           74.5             80.9           74.5
Gross Profit                                     21.1           25.5             19.1           25.5
Selling, General and
     Administrative Expenses                     11.6           13.8             12.8           14.1
Plant Closing and Reorganization Costs              -            5.2              2.9            1.8
Management Restructuring                          1.2              -              2.7              -
Amortization of Goodwill                          2.0            2.1              2.1            2.1
                                                 -----         ------           ------         ------
(Loss) Income from Operations                     6.3            4.4             (1.4)           7.5
Interest Expense                                 (9.5)         (10.3)           (10.2)         (10.2)
Interest Income                                   0.1            0.1              0.1            0.3
Other Income, net                                 0.4            0.8              0.5            0.3
                                                 -----         ------           ------         ------
Loss before (Benefit) Provision

     for Income Taxes                            (2.7)          (5.0)           (11.0)          (2.1)
(Benefit) Provision for Income
     Taxes                                       (0.2)           1.0             (3.3)           0.9
                                                 -----         ------           ------         ------
Net Loss                                         (2.5)%         (6.0)%           (7.7)%         (3.0)%
                                                 =====         ======           ======         ======
</TABLE>


Results for the quarter and year-to-date periods were impacted by: (i) the
recognition of various charges (see Plan of Restructuring and Reorganization
above); (ii) the acquisition of Alfa on June 30, 1997 (see Note 11) as operating
results from this subsidiary are included in the nine months ended October 3,
1998, but are only included in 1997 from July 1; (iii) the acquisition of NOVA
on June 9, 1998 (see Note 11) as operating results of this subsidiary are
included in the quarter and nine months ended October 3, 1998, but are not
included in the comparable periods in 1997; and (iv) the divestiture of the
American Granby accessory business in May 1997 (see Note 10) as 1998 does not
include the accessory business operating results which are included in the
comparable nine month period in 1997.






                                       12

<PAGE>   14
AMTROL INC. AND SUBSIDIARIES
--------------------------------------------------------------------------------

                     MANAGEMENT'S DISCUSSION AND ANALYSIS OF
                  RESULTS OF OPERATIONS AND FINANCIAL CONDITION


THIRD QUARTER ENDED OCTOBER 3, 1998

Net sales for the third quarter increased $7.4 million or 15.4% compared to the
same period in 1997. The quarter-to-quarter comparison is favorably impacted by
the acquisition of NOVA in 1998. Excluding NOVA, third quarter 1998 net sales
would have increased approximately $3.4 million or 7.0%. Net sales in North
America, adjusted for certain markets transferred to Alfa in 1998, increased
2.3% in the 1998 third quarter compared to 1997, while Alfa sales increased
31.5% in 1998 compared to 1997.

The gross margin percentage for the third quarter of 1998 declined to 21.1% from
25.5% in the third quarter of 1997. The decline in the gross margin percentage
is mainly attributable to increased production costs of approximately $1.1
million resulting from difficulties in achieving efficient production levels on
the production lines relocated to West Warwick from Nashville. Increased
production costs include higher labor, maintenance and scrap, as well as factory
overhead. Significant efforts are underway to increase productivity and decrease
costs on the relocated lines; however, the Company does not expect to completely
eliminate these inefficiencies until the second quarter of 1999.

Selling, General and Administrative expenses for the 1998 third quarter declined
approximately $0.2 million from 1997 mainly due to cost reductions initiated in
the quarter, off-set by the inclusion of NOVA in 1998 but not 1997. As a
percentage of net sales, excluding the NOVA acquisition, third quarter 1998
selling, general and administrative expenses declined to 12.0% from 13.8% in
1997.

Earnings before interest expense, taxes, depreciation and amortization (EBITDA)
in the third quarter of 1998, adjusted for costs associated with the
restructuring and reorganization plan and incremental production inefficiencies,
amounted to $8.4 million, compared to $7.7 million in the 1997 third quarter, an
increase of $0.7 million or 9.1%.

Goodwill amortization expense of $1.1 million for the third quarter of 1998
increased from $1.0 million in 1997 due to the acquisition of Nova in 1998.

The pretax loss for the third quarter was $1.5 million, a decrease of
approximately $0.9 million from the third quarter 1997 pretax loss. The decrease
was largely the result of the inclusion in 1997 of the $2.5 million pre-tax
charge relating to the closure of the Singapore facility, off-set in 1998 by the
lower gross profit and management restructuring charges as discussed above.




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                     MANAGEMENT'S DISCUSSION AND ANALYSIS OF
                  RESULTS OF OPERATIONS AND FINANCIAL CONDITION


NINE MONTHS ENDED OCTOBER 3, 1998

Net sales for the nine months ended October 3, 1998 increased $18.2 million or
13.3% compared to the same period in 1997. The year-to-year comparison is
favorably impacted by the acquisition of NOVA and the full year inclusion of
Alfa. Excluding the impact of Alfa, NOVA, and American Granby (sold in May 1997)
and the impact of certain markets transferred to Alfa from North America in
1998, net sales would have decreased approximately 3.6%. The unseasonably warm
winter negatively impacted sales of products to the plumbing and heating
industry while the wet weather delayed the installation of new water wells. In
addition, sales of certain products were adversely impacted by a manufacturing
process problem, which has since been corrected, and by a supply problem
resulting from the relocation of certain production lines from the Company's
Nashville, Tennessee production facility to its West Warwick, R.I. facility.

During the second quarter of 1998, the Company recorded a provision for abnormal
warranty costs of $4.5 million to reflect the incremental warranty costs
associated with a 1995/1996 production problem. The problem has since been
corrected but the Company is still experiencing higher than normal warranty
claims for some products manufactured during the 1995/1996 production period.
Accordingly, the Company reassessed its potential future liability associated
with this product and determined that an additional warranty provision of $4.5
million was required.

Excluding the provision for abnormal warranty costs, gross profit for the nine
months ended October 3, 1998 declined by $0.8 million or 2.4% in comparison to
the same period in 1997. The decline in the gross margin is mainly attributable
to increased production costs of approximately $2.8 million resulting from
difficulties in achieving efficient production levels on the production lines
relocated to West Warwick from Nashville. Increased production costs include
higher labor, maintenance and scrap, as well as factory overhead. The gross
profit percentage decreased to 22.0% in 1998 from 25.5% in 1997 primarily due to
the inclusion of sales by Alfa and NOVA which generate lower average margins
than other Company products and the production inefficiencies associated with
the relocated production lines.

As previously noted, the Company transferred certain production lines from its
Nashville facility to its West Warwick, Rhode Island facility in December 1997.
In connection with the relocation, the Company incurred incremental plant
closing costs in the 1998 second quarter of $4.5 million resulting from
unexpected retrofitting and reconditioning required for the relocated equipment,
damage to equipment during shipment, and delays in preparing the Nashville
building for sale. This amount has been reflected in the accompanying financial
statements.




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                     MANAGEMENT'S DISCUSSION AND ANALYSIS OF
                  RESULTS OF OPERATIONS AND FINANCIAL CONDITION


Also as noted above, the Company, in connection with its Plan of Restructuring
and Reorganization, has discontinued certain product lines and has taken actions
to reduce the number of variations offered on many of its products, thereby
reducing inventory levels. Certain members of senior management have left the
Company in connection with the Plan. The unrecoverable cost of discontinued
inventory and the cost of programs to reduce the number of product offerings,
combined with the cost of post employment benefits for departing executives,
aggregates approximately $4.6 million and has been reflected in the accompanying
financial statements.

Selling, General and Administrative expenses for the nine months ended October
3, 1998 increased approximately $0.5 million from 1997 mainly due to $0.4
million of expenses incurred in 1998 relating to an acquisition which was not
completed; and the inclusion of NOVA in 1998 but not 1997. As a percentage of
net sales (excluding the cost of the abandoned acquisition), selling, general
and administrative expenses declined to 12.5% in 1998 from 14.1% for the same
period in 1997.

Earnings before interest expense, taxes, depreciation and amortization (EBITDA)
for the nine months ended October 3, 1998, before costs associated with the
restructuring and reorganization plan, incremental production inefficiencies and
the abnormal warranty provision, amounted to $23.6 million, compared to $20.8
million for the nine months ended October 4, 1997, an increase of $2.8 million
or 13.6%.

For the nine months ended October 3, 1998, goodwill amortization expense
increased $0.4 million over the comparable period in 1997 to $3.3 million and
interest expense increased $1.9 million over 1997 to $15.8 million. The increase
in both amortization and interest expense primarily relates to the acquisition
and financing of Alfa and NOVA and short-term working capital needs earlier in
1998.

The year-to-date pretax loss is $17.0 million, an increase of approximately
$14.1 million over the year-to-date 1997 pretax loss. The increase was largely
the result of the costs of the restructuring and reorganization plan, abnormal
warranty provision and manufacturing inefficiencies associated with the
relocated production lines.

LIQUIDITY AND CAPITAL RESOURCES

Working Capital at October 3, 1998 was $17.5 million and the ratio of current
assets to current liabilities was 1.31 to 1.0. This compares with working
capital of $24.4 million and a current ratio of 1.57 to 1.0 at December 31,
1997.



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                     MANAGEMENT'S DISCUSSION AND ANALYSIS OF
                  RESULTS OF OPERATIONS AND FINANCIAL CONDITION


The Company's accounts receivable increased $9.2 million since December 31,
1997, reflecting seasonal demand, the inclusion of Nova, and increases at Alfa
due to higher sales and the weaker dollar compared to the Portuguese Escudo.
Inventory declined approximately $2.6 million. North American inventories
decreased $10.9 million, offset by combined Alfa and Nova inventory increases of
$8.3 million. Inventory levels in North America, particularly water systems,
were temporarily increased at the end of 1997 in order to assure uninterrupted
supply to customers during the relocation of the Company's Nashville production
lines to its West Warwick, R.I. facility. In addition, inventory in North
America decreased in connection with an inventory reduction program initiated in
the third quarter. The inventory increase at Alfa relates to the higher level of
production at that facility. Accounts payable and accrued expenses combined
increased from the previous year-end by approximately $9.9 million primarily due
to the addition of NOVA, increases at Alfa associated with higher inventory at
that location, and the weaker dollar compared to the Portuguese Escudo.

The Company's cash balance remained unchanged at $0.5 million as compared to the
end of 1997. During this same period, the Company invested approximately $9.4
million in capital assets and decreased net borrowings by $3.9 million.

The Company's total capital expenditures for 1998 are projected to approximate
$10.5 million. The projection reflects planned capital investments at the Alfa
facility intended to improve productivity at that location and expenditures at
the Company's West Warwick, Rhode Island facility to improve productivity on
relocated production lines.

On July 31, 1998, the Cypress Group L.L.C. and members of senior management
contributed an additional $20.5 million of new equity into the Company's parent,
AMTROL Holdings Inc. In turn, AMTROL Holdings Inc. contributed a like amount to
the Company. The additional capital contribution primarily was used to repay
borrowings under the Company's Bank Credit Agreement.



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                     MANAGEMENT'S DISCUSSION AND ANALYSIS OF
                  RESULTS OF OPERATIONS AND FINANCIAL CONDITION


The Bank Credit Agreement (the "Agreement") between the Company and a syndicate
of lenders was amended on July 31, 1998 to allow for the early repayment of a
portion of the principal outstanding and to modify certain loan agreement
covenants to be more in line with the Company's business plans. The Agreement,
as amended, provides for senior term loans (the "Term Loans") and a Revolving
Credit Facility. In connection with the amendment to the Agreement, the company
repaid $20.5 million on August 3, 1998. A portion ($10.2 million) of the Term
Loans (the "Tranche A Term Loans") will mature five and one-half years after the
effective date, November 13, 1996, with quarterly amortization payments during
the term of such loans. As a result of the August 3, 1998 repayment, no further
amortization payments on Tranche A term loans will be required in 1998. The
remainder ($44.5 million) of the Term Loans (the "Tranche B Term Loans") will
mature seven and one-half years after the effective date, with nominal quarterly
amortization prior to the maturity of the Tranche A Term Loans and with the
remaining amounts amortizing on a quarterly basis thereafter. The Revolving
Credit Facility of $30.0 million includes a sublimit providing for up to $20.0
million of availability on a revolving credit basis to finance permitted
acquisitions. The commitments under the Revolving Credit Facility and the
acquisition sublimit will reduce by $5.0 million in the fourth year and $10.0
million in the fifth year after the effective date. The Revolving Credit
Facility will mature five and one-half years after the effective date. The Bank
Credit Agreement is secured by substantially all assets of the Company and its
domestic subsidiaries.

The Company issued $115.0 million of Senior Subordinated Notes due 2006 (the
"Notes") under an Indenture dated as of November 13, 1996. The Notes are
unsecured obligations of AMTROL. The Notes bear interest at a rate of 10.625%
per annum which is payable semi-annually on each June 30 and December 31
commencing on June 30, 1997. In addition, on or prior to December 31, 1999, the
Company may use the net cash proceeds of one or more public equity offerings to
redeem up to 35% of the aggregate principal amount of the Notes originally
issued at a redemption price of 110.625% of the principal amount thereof plus
accrued interest to the date of redemption. Upon a "Change of Control" (as
defined in the Indenture), each Note holder has the right to require the Company
to repurchase such holder's Notes at a purchase price of 101% of the principal
amount plus accrued interest.

The Company intends to fund its future working capital expenditures and debt
service requirements through cash flows generated from operations, borrowings
under the revolving credit facility (the "Revolving Credit Facility") provided
under the Bank Credit Agreement and through the use of available cash balances
($0.5 million at October 3, 1998).

Management believes that cash generated from operations, together with
borrowings available under the Revolving Credit Facility, will be sufficient to
meet the Company's working capital and capital expenditure needs in the
foreseeable future. The Company may consider other options available to it in
connection with funding future working capital and capital expenditure needs,
including the issuance of additional debt and equity securities.







                                       17




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                     MANAGEMENT'S DISCUSSION AND ANALYSIS OF
                  RESULTS OF OPERATIONS AND FINANCIAL CONDITION

INFLATION

In recent years, inflation has been modest and has not had a material impact
upon the results of the Company's operations.

YEAR 2000 COMPLIANCE

The Year 2000 issue is the result of computer programs being written using two
digits rather than four to define the applicable year. Any of the Company's
computer programs that have time-sensitive software may recognize a date using
"00" as the Year 1900 rather than the Year 2000. The Company is in the process
of implementing a new Enterprise Resource Planning System ("ERP") which, in
addition to providing the Company with a wide-range of operational and
administrative efficiencies, should ensure that virtually all of the Company's
core business systems are year 2000 compliant. A portion of this system was
implemented during the third quarter of 1998. The Company anticipates completion
of the project before the end of the 1999 first quarter. The date on which the
Company believes it will complete the ERP Project is based on management's best
estimate. However, there can be no guarantee that this estimate will be achieved
and actual results could differ materially from those anticipated. The Company
will develop a contingency plan in the first quarter of 1999 if it appears that
the ERP will not be completed as planned. The cost of Year 2000 compliance
cannot be separated from the overall cost of the ERP, but the company believes
that such incremental costs are not material. All remaining business software
programs are expected to be made Year 2000 compliant by mid-1999, including
those supplied by vendors, or they will be retired.

The Company has begun to initiate formal communications with its most
significant suppliers to determine the extent to which the Company's interface
systems are vulnerable to those third parties' failure to remediate their own
Year 2000 issues. The Company will initiate formal communications with its large
customers by the end of 1998 to assess the same issue. While there can be no
guarantee that the systems of other companies on which the Company's system rely
will be timely converted and will not have an adverse effect on the Company's
systems, the Company does not believe that its operations are materially
vulnerable to the failure of any vendor or customer to properly address the Year
2000 issue. The Company has determined it has no exposure to contingencies
related to the Year 2000 issue for the products it has sold.

The Company has also begun to initiate formal communications with the vendors
supplying manufacturing equipment utilizing hardware, software and associated
embedded computer chips. It estimates that this portion of its Year 2000
compliance program will be completed by the end of 1998.



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                     MANAGEMENT'S DISCUSSION AND ANALYSIS OF
                  RESULTS OF OPERATIONS AND FINANCIAL CONDITION


The failure to correct a material Year 2000 problem could result in an
interruption in, or failure of, certain normal business activities or
operations. Such failures could materially and adversely affect the Company's
results of operations, liquidity and financial condition. Due to the general
uncertainty inherent in the Year 2000 problem, resulting in part from the
uncertainty of the Year 2000 readiness of third-party suppliers and customers,
the Company is unable to determine at this time whether the consequences of Year
2000 failures will have a material impact on the Company's results of
operations, liquidity or financial condition. The aforementioned steps being
undertaken by the Company are expected to significantly reduce the Company's
level of uncertainty about the Year 2000 problem and, in particular, about the
Year 2000 compliance and readiness of its material suppliers and customers. The
Company believes that, with the implementation of ERP and the other steps being
taken, the possibility of significant interruptions of normal operations should
be reduced.







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AMTROL INC. AND SUBSIDIARIES
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                                     PART II



ITEM 6.     EXHIBITS AND REPORTS ON FORM 8-K

            EXHIBITS

            10.1.4 Fourth Amendment to the Credit Agreement dated July 13, 1998.

            REPORTS ON FORM 8-K

            No reports on form 8-K were filed during the period covered by this 
            report.






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


SIGNATURES


Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.



                                    AMTROL INC.


Date: November 16, 1998             By: /s/ Albert D. Indelicato
      -----------------                 ----------------------------------------
                                        Albert D. Indelicato
                                        President,
                                        Chief Executive Officer and Director



Date: NOVEMBER 16, 1998             By: /s/ Donald W. Reilly
      -----------------                 ----------------------------------------
                                        Donald W. Reilly,
                                        Vice President,
                                        Chief Financial Officer and Treasurer





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