<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:       July 3, 1999
                                      ------------

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 July 3, 1999

<PAGE>   2



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




                  FORM 10-Q FOR THE QUARTER ENDED JULY 3, 1999



                                      INDEX



                                                                          PAGE
                                                                          ----
PART I.      FINANCIAL INFORMATION

  Item 1.    Consolidated Balance Sheets -
                 July 3, 1999 and December 31, 1998                        2

             Consolidated Statements of Operations -
                 For the Quarter and Six Months Ended July 3, 1999
                 and July 4, 1998                                          3

             Consolidated Statement of Shareholders' Equity -
                 For the Six Months Ended July 3, 1999                     4

             Consolidated Statements of Cash Flows -
                 For the Six Months Ended July 3, 1999 and July 4, 1998    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                              18

                Signatures                                                 19



                                       1

<PAGE>   3

<TABLE>
<CAPTION>
                                    AMTROL INC. AND SUBSIDIARIES

                                     CONSOLIDATED BALANCE SHEETS
                                     (UNAUDITED - IN THOUSANDS)

                                        ASSETS

                                                                       JULY 3,        DECEMBER 31,
                                                                        1999              1998
                                                                      ---------       ------------
<S>                                                                   <C>              <C>
CURRENT ASSETS:
      Cash and cash equivalents                                       $      53        $   1,088
      Accounts receivable, less allowance for doubtful accounts          36,435           28,938
      Inventories                                                        21,958           24,319
      Prepaid income taxes                                                2,104            2,271
      Prepaid expenses and other                                          2,901            3,241
      Assets held for sale                                                   --              572
                                                                      ---------        ---------
         Total current assets                                            63,451           60,429
                                                                      ---------        ---------

PROPERTY, PLANT AND EQUIPMENT, NET                                       47,369           51,783

OTHER ASSETS:
      Goodwill                                                          168,780          171,166
      Deferred financing costs                                            6,251            6,770
      Deferred income taxes                                               8,208            8,205
      Other                                                               2,389            2,314
                                                                      ---------        ---------
                                                                        185,628          188,455
                                                                      ---------        ---------
                                                                      $ 296,448        $ 300,667
                                                                      =========        =========
                         LIABILITIES AND SHAREHOLDERS' EQUITY

CURRENT LIABILITIES
      Current maturities of long-term debt                            $   3,880        $   4,043
      Notes payable to banks                                              4,203           10,660
      Accounts payable                                                   24,393           21,193
      Accrued expenses                                                   15,089           14,242
      Accrued interest                                                    1,058              777
      Accrued income taxes                                                4,626            2,872
                                                                      ---------        ---------
         Total current liabilities                                       53,249           53,787
                                                                      ---------        ---------

LONG TERM DEBT, LESS CURRENT MATURITIES                                 172,640          173,023

OTHER NONCURRENT LIABILITIES                                              6,843            7,909

SHAREHOLDERS' EQUITY
      Capital stock $.01 par value - authorized 1,000 shares,
         100 shares issued                                                   --               --
      Additional paid-in capital                                         90,073           89,823
      Retained deficit                                                  (24,169)         (24,363)
      Accumulated other comprehensive (loss) income                      (2,188)             488
                                                                      ---------        ---------
         Total shareholders' equity                                      63,716           65,948
                                                                      ---------        ---------
                                                                      $ 296,448        $ 300,667
                                                                      =========        =========
</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                 SIX MONTHS ENDED
                                                   ------------------------        -------------------------
                                                    JULY 3,          JULY 4,         JULY 3,         JULY 4,
                                                     1999            1998             1999            1998
                                                   --------        --------        ---------        --------
<S>                                                <C>             <C>             <C>              <C>
NET SALES                                          $ 55,909        $ 50,935        $ 110,318        $ 99,351

COST OF GOODS SOLD-Note 6                            40,664          44,648           81,150          81,422
                                                   --------        --------        ---------        --------

          GROSS PROFIT                               15,245           6,287           29,168          17,929

OPERATING EXPENSES
Selling, general and administrative                   7,155           6,933           15,364          13,364
Plant closing and
     reorganization costs-Note 6                         --           4,450               --           4,450
Management restructuring-Note 6                          --           3,500               --           3,500
Amortization of goodwill                              1,115           1,223            2,231           2,319
                                                   --------        --------        ---------        --------
          Income (loss) from operations               6,975          (9,819)          11,573          (5,704)

OTHER INCOME (EXPENSE):
Interest expense                                     (4,871)         (5,267)          (9,922)        (10,466)
Interest income                                          32              42               56              74
License and distributorship fees                         45              68               90              98
Other, net                                               65             323              162             524
                                                   --------        --------        ---------        --------
          Income (loss) before provision for
             (benefit from) income taxes              2,246         (14,653)           1,959         (15,474)

PROVISION FOR (BENEFIT FROM)
     INCOME TAXES                                     1,312          (5,100)           1,765          (4,962)
                                                   ========        ========        =========        ========
          NET INCOME (LOSS)                        $    934        $ (9,553)       $     194        $(10,512)
                                                   ========        ========        =========        ========
</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
                                               COMMON        PAID - IN           RETAINED         COMPREHENSIVE
                                               STOCK          CAPITAL            DEFICIT           INCOME (LOSS)
                                             --------       ----------          ---------         --------------

<S>                                            <C>            <C>                <C>                  <C>
BALANCE, December 31, 1998                       -            $89,823            ($24,363)            $   488
      Capital Contribution                       -                250                  --                  --
      Net Income                                 -                 --                 194                  --
      Currency Translation Adjustment            -                 --                  --              (2,676)
                                               -----          -------            --------             -------
BALANCE, July 3, 1999                            -            $90,073            ($24,169)            ($2,188)
                                               =====          =======            ========             =======
</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>

                                                                                SIX MONTHS ENDED
                                                                           -------------------------
                                                                            JULY 3,          JULY 4,
                                                                             1999             1998
                                                                           --------         --------
<S>                                                                        <C>              <C>
CASH FLOWS FROM OPERATING ACTIVITIES:
     Net income (loss)                                                     $    194         $(10,512)
     Adjustments to reconcile net income (loss) to net cash
          provided by (used in) operating activities -
           Depreciation and amortization                                      7,151            6,408
           Provision for losses on accounts receivable                          123               94
           Non-cash charges                                                      --           11,600
           Gain on sale of fixed assets                                          --             (142)
     Changes in operating assets and liabilities                             (1,608)         (11,872)
                                                                           --------         --------
                Net cash provided by (used in) operating activities           5,860           (4,424)

CASH FLOWS FROM INVESTING ACTIVITIES:
     Acquisition of NOVA, net of cash acquired                                   --           (5,855)
     Proceeds from sale of property, plant and equipment                        961              642
     Capital expenditures                                                    (2,665)          (7,342)
                                                                           --------         --------
                Net cash used in investing activities                        (1,704)         (12,555)

CASH FLOWS FROM FINANCING ACTIVITIES:
     Repayment of debt                                                      (23,039)         (10,689)
     Issuance of debt                                                        17,691           27,829
     Capital contribution                                                       250               --
                                                                           --------         --------
                Net cash (used in) provided by financing activities          (5,098)          17,140
                                                                           --------         --------

NET (DECREASE) INCREASE IN CASH AND CASH
EQUIVALENTS                                                                    (942)             161

Effect of exchange rate changes on cash and cash equivalents                    (93)              (3)

Cash and Cash Equivalents, beginning of period                                1,088              544

                                                                           ========         ========
Cash and Cash Equivalents, end of period                                   $     53         $    702
                                                                           ========         ========
</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., the 1997 acquisition of Petroleo
     Mecanica ALFA, S.A. ("ALFA") and the 1998 acquisition of NOVA
     Wassererwarmer GmbH ("NOVA") and is included in other assets. Goodwill is
     being amortized up to 40 years.


<PAGE>   8

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


                NOTES TO CONSOLIDATED FINANCIAL STATEMENTS-CONT.
                                   (UNAUDITED)

     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.

     RECLASSIFICATIONS

     Certain amounts in prior periods have been reclassified to permit
     comparison to the current year presentation.

4.   INVENTORIES

     Inventories are stated at the lower of cost or market and were as follows
     (in thousands):

<TABLE>
<CAPTION>

                                               JULY 3,             DECEMBER 31,
                                                1999                  1998
                                              ---------           ------------
<S>                                           <C>                   <C>
    Raw materials and work in process         $ 11,906              $ 14,548
    Finished goods                              10,052                 9,771
                                              --------              --------
                                              $ 21,958              $ 24,319
                                              ========              ========
</TABLE>



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, $9.6 million at
     July 3, 1999, and a seven and one-half year Tranche B Term Loan, $44.0
     million at July 3, 1999, (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.

     Under the terms of the Agreement, AMTROL is required to comply, and is in
     compliance, with certain financial covenants and restrictions as of July 3,
     1999.


                                       7
<PAGE>   9

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


                NOTES TO CONSOLIDATED FINANCIAL STATEMENTS-CONT.
                                   (UNAUDITED)


6.   1998 PLANT CLOSING, REORGANIZATION AND RESTRUCTURING CHARGES

     The Company recorded aggregate charges of $14.5 million in the 1998 second
     quarter primarily related to a management restructuring and reorganization,
     abnormal warranty costs associated with a production problem (since
     corrected) and relocating and consolidating certain production lines. The
     abnormal warranty charge and manufacturing inefficiencies associated with
     the relocation of production are included in cost of sales.


7.   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 1999 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.   COMPREHENSIVE INCOME

     The total comprehensive loss, which is comprised of the net income (loss)
     and the foreign currency translation adjustment, was as follows:

<TABLE>
<CAPTION>
                                    QUARTER ENDED         SIX MONTHS ENDED
                                 ------------------      -------------------
                                 JULY 3,    JULY 4,     JULY 3,     JULY 4,
                                  1999        1998        1999        1998
                                 -------    -------     -------     --------
<S>                               <C>        <C>         <C>        <C>
      Total Comprehensive Loss    $226       $9,635      $2,482     $10,782
</TABLE>


9.   ACQUISITION

     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


                                       8
<PAGE>   10
AMTROL INC. AND SUBSIDIARIES
--------------------------------------------------------------------------------

                NOTES TO CONSOLIDATED FINANCIAL STATEMENTS-CONT.
                ------------------------------------------------
                                  (UNAUDITED)
                                  -----------

     acquisition date. The following represents proforma net sales and net loss
     for the second quarter and year-to-date July 4, 1998, respectively, as
     though the acquisition of NOVA occurred as of January 1, 1998 (in
     thousands): Net sales $53,324 and $104,629, net loss $9,487 and $10,778.

10.  BUSINESS SEGMENT INFORMATION

     The Company adopted SFAS No. 131, Disclosure about Segments of an
     Enterprise and Related Information, in 1998. AMTROL's reportable segments
     are delineated geographically. The segments are managed separately because
     of their different product offerings, markets served, manufacturing
     processes and cost structures.

     The Company's North American segment operates manufacturing facilities in
     Rhode Island, Kentucky, Maryland and Ohio, and operates a distribution
     facility in Ontario, Canada. This segment manufactures and markets products
     used principally in flow control, storage, heating, and other treatment of
     fluids in the water system and HVAC markets. These products are marketed
     throughout the world but primarily in North America, Western Europe, Asia
     and Mexico.

     The Company's European segment includes the Company's facilities in
     Guimaraes, Portugal and Donaueschingen, Germany. The Guimaraes facility
     manufactures returnable and non-returnable steel gas cylinders for storing
     cooking, heating and refrigerant gases which are marketed throughout
     Europe, the Middle East and Africa, as well as the Far East. The
     Donaueschingen facility, acquired during the second quarter of 1998,
     manufactures and distributes residential and commercial water heaters which
     are marketed primarily in Switzerland, Austria and Germany.

     The primary criteria by which financial performance is evaluated and
     resources are allocated include revenues and operating income. The
     following is a summary of key financial data by segment:



                                       9
<PAGE>   11

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


                NOTES TO CONSOLIDATED FINANCIAL STATEMENTS-CONT.
                                   (UNAUDITED)

<TABLE>
<CAPTION>
                                          QUARTER ENDED                  SIX MONTHS ENDED
                                     -----------------------         ------------------------
                                     JULY 3,         JULY 4,          JULY 3,         JULY 4,
                                      1999            1998             1999            1998
                                     -------        --------         --------        --------
<S>                                  <C>            <C>              <C>             <C>
SALES TO EXTERNAL CUSTOMERS
   North America                     $38,443        $ 36,804         $ 75,092        $ 73,971
   Europe                             17,466          14,131           35,226          25,380
                                     -------        --------         --------        --------
   Consolidated                      $55,909        $ 50,935         $110,318        $ 99,351
                                     =======        ========         ========        ========

INCOME (LOSS) FROM OPERATIONS
   North America                     $ 5,056        $(11,135)        $  8,531        $ (8,383)
   Europe                              1,919           1,316            3,042           2,679
                                     -------        --------         --------        --------
   Consolidated                      $ 6,975        $ (9,819)        $ 11,573        $ (5,704)
                                     =======        ========         ========        ========
</TABLE>


                                       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; 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.





<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                   SIX MONTHS ENDED
                                               ----------------------           -----------------------
                                               JULY 3,        JULY 4,           JULY 3,         JULY 4,
                                                1999           1998              1999            1998
                                               -------        -------           -------         -------
<S>                                            <C>            <C>               <C>             <C>
Net Sales                                      100.0%         100.0%            100.0%          100.0%
Cost of Goods Sold                              72.7           87.7              73.6            81.9
                                               -----          -----             -----           -----
Gross Profit                                    27.3           12.3              26.4            18.1
Selling, General and
     Administrative Expenses                    12.8           13.6              13.9            13.5
Plant Closing and Reorganization Costs             -            8.7                 -             4.5
Management Restructuring                           -            6.9                 -             3.5
Amortization of Goodwill                         2.0            2.4               2.0             2.3
                                               -----          -----             -----           -----
Income (Loss) from Operations                   12.5          (19.3)             10.5            (5.7)
Interest Expense                                (8.7)         (10.3)             (9.0)          (10.6)
Interest Income                                  0.1            0.1               0.1             0.1
Other Income, net                                0.2            0.7               0.2             0.6
                                               -----          -----             -----           -----
Income (loss) before Provision for
     (Benefit from) Income Taxes                 4.1          (28.8)              1.8           (15.6)
Provision for (Benefit from) Income
     Taxes                                       2.4          (10.0)              1.6            (5.0)
                                               =====          =====             =====           =====
Net Income (Loss)                                1.7%         (18.8)%             0.2%          (10.6)%
                                               =====          =====             =====           =====
</TABLE>


Results for the quarter and year-to-date periods are impacted by the acquisition
of NOVA Wassererwarmer GmbH ("NOVA") on June 9, 1998 (see Note 9) as operating
results of this subsidiary are included in the quarter and six months ended July
3, 1999, but are only included in 1998 from the acquisition date.

SECOND QUARTER ENDED JULY 3, 1999

Net sales for the second quarter increased $5.0 million or 9.8% compared to the
same period in 1998. Second quarter 1999 sales were the highest in the Company's
history. The quarter-to-quarter comparison is favorably impacted by the
acquisition of NOVA. Excluding the impact of this acquisition, second quarter
1999 net sales would have increased approximately 6.8%. Sales in North America,
adjusted for certain markets which were transferred to ALFA from North America
starting in May 1998, increased by 8.1% in the 1999 second quarter compared to
1998. European sales, excluding the impact of NOVA and markets transferred from
North

                                       12
<PAGE>   14

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


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


America, increased 2.1% in the second quarter of 1999 compared to the same
quarter in 1998. Including NOVA, second quarter 1999 sales in Europe increased
23.6% compared to 1998.

The gross profit for the second quarter of 1999 increased from the second
quarter of 1998, excluding the 1998 provision for abnormal warranty costs, by
$4.5 million or 41.3% with the margin percentage increasing to 27.3% from 21.1%.
Excluding the results of NOVA, the margin percentage for the second quarter
would have been 28.4%. The higher margins in 1999 are mainly attributable to
productivity improvements at the Company's West Warwick, Rhode Island
manufacturing facility and to favorable product mix.

Selling, General and Administrative expenses for the 1999 second quarter
increased approximately $0.2 million from 1998, and as a percentage of sales,
decreased to 12.8% in 1999 from 13.6% in 1998.

Earnings before interest expense, taxes, depreciation and amortization (EBITDA)
in the second quarter of 1999 increased $16.8 million to $10.4 million, compared
to $(6.4) million in the 1998 second quarter. The second quarter of 1998
included restructuring and reorganization costs, costs related to a plant
relocation and abnormal warranty costs aggregating $14.5 million. Second
quarter, 1999 EBITDA was the highest in the Company's history.

Goodwill amortization expense of $1.1 million for the second quarter of 1999 was
relatively unchanged from the second quarter of 1998, and interest expense of
$4.9 million for the second quarter decreased $0.4 million over the comparable
1998 period. The decrease in interest expense primarily relates to the reduction
of debt offset by the acquisition and financing of NOVA.

Pretax income for the second quarter was $2.2 million, an increase of
approximately $16.9 million over the second quarter 1998 pretax loss.


SIX MONTHS ENDED JULY 3, 1999

Net sales for the six months ended July 3, 1999 increased $11.0 million or 11.0%
compared to the same period in 1998. The year-to-year comparison is favorably
impacted by the acquisition of NOVA. Excluding the impact of this acquisition,
year-to-date second quarter 1999 net sales would have increased approximately
6.5%. Sales in North America, adjusted for certain markets which were
transferred to ALFA from North America starting in May 1998, increased by 7.3%
for the six months ended July 3, 1999 compared to the same period in 1998.
European sales, excluding the impact of NOVA and markets transferred from North
America, increased 3.8% in 1999 compared to the same period in 1998. Including
NOVA, year-to-date 1999 sales in Europe increased 38.8% compared to the
comparable 1998 period.

The gross profit and margin percentage for the six months ended July 3, 1999
were impacted

                                       13

<PAGE>   15


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


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


by the same factors as those affecting the second quarter. Gross profit
increased by $6.7 million or 30.1% in comparison to the same period in 1998
(excluding the provision for abnormal warranty costs). The gross profit
percentage increased to 26.4% in 1999 from 22.6% in 1998, primarily due to
productivity improvements at the Company's West Warwick, Rhode Island
manufacturing facility and to favorable product mix. Excluding the results of
NOVA, the margin percentage for the first six months of 1999 would have been
27.5%.

Selling, General and Administrative expenses for the six months ended July 3,
1999 increased approximately $2.0 million from 1998. The increase is mainly
attributable to the inclusion of NOVA in all of 1999 but for only one month
in 1998. As a percentage of net sales, selling, general and administrative
expenses were approximately the same in 1999 as in 1998.

Earnings before interest expense, taxes, depreciation and amortization (EBITDA)
for the six months ended July 3, 1999 increased $17.8 million to $18.5 million,
compared to $0.7 million for the six months ended July 4, 1998. The six months
ended July 4, 1998 included restructuring and reorganization costs, costs
related to a plant relocation and abnormal warranty costs aggregating $14.5
million.

For the six months ended July 3, 1999, goodwill amortization expense of $2.2
million was relatively unchanged from the comparable period in 1998 and interest
expense decreased $0.5 million from 1998 to $9.9 million. The decrease in
interest expense primarily relates to the reduction of debt offset by the
acquisition and financing of NOVA.

Year-to-date net income was $0.2 million, an increase of approximately $10.7
million over the year-to-date 1998 net loss.

LIQUIDITY AND CAPITAL RESOURCES

Working Capital at July 3, 1999 was $10.2 million and the ratio of current
assets to current liabilities was 1.19 to 1.0. This compares with working
capital of $6.6 million and a current ratio of 1.12 to 1.0 at December 31, 1998.
The increase in working capital resulted, in part, from an increase in accounts
receivable of $7.5 million, offset by an inventory decline of approximately $2.4
million. The increase in receivables and the decrease in inventory are primarily
the result of higher sales. Accounts payable and accrued expenses combined
increased from the previous year-end by approximately $4.0 million, largely due
to the timing of payments.

The Company's cash balance declined $1.0 million as compared to the end of 1998.
During this same period, the Company invested approximately $2.7 million in
plant and equipment and decreased net borrowings by $7.0 million.

The Company's total capital expenditures for 1999 are projected to approximate
$8.5 million. The projection reflects planned capital investments at the
Guimaraes, Portugal and West Warwick, Rhode Island facilities to improve
productivity and additional investments in


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


information systems at all of the Company's locations.

The Company is a party to a Bank Credit Facility (the "Facility") which consists
of $53.6 million of senior term loans (the "Term Loans") and a $30.0 million
revolving credit facility (the "Revolving Credit Facility"). A portion ($9.6
million) of the Term Loans (the "Tranche A Term Loans") will mature on May 13,
2002, with quarterly amortization payments during the term of such loans. The
remainder ($44.0 million) of the Term Loans (the "Tranche B Term Loans") will
mature on May 13, 2004, 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 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 each reduce by $5.0 million on November 13, 2000 and
$10.0 million on November 13, 2001. The Revolving Credit Facility will mature on
May 13, 2002. At July 3, 1999, amounts available under the revolver approximated
$25.4 million. The Bank Credit Facility 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 Bank Credit Facility and the Indenture contain various affirmative and
negative covenants and restrictions. The Company was in compliance with all such
covenants at July 3, 1999.

In the second quarter, members of the Company's management contributed an
additional $0.3 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
Company's management agreed to make additional capital contributions of $0.6
million to AMTROL Holdings Inc. over the next two years.

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


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


needs, including the issuance of additional debt and equity securities.

INFLATION

The Company believes that inflation does not have a material effect on its
results of operations or financial condition. To insulate against fluctuating
prices, the Company has negotiated annual contracts with suppliers of certain
key raw materials (primarily steel) for a significant percentage of its expected
usage through 1999.

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 has recently
completed the implementation of a new Enterprise Resource Planning System
("ERP") in its West Warwick, Rhode Island corporate headquarters. The ERP, in
addition to providing the Company with a wide-range of operational and
administrative efficiencies, supports most of the Company's North American
operations and ensures that virtually all of the Company's core business systems
are Year 2000 compliant. All remaining business software programs are expected
to be made Year 2000 compliant by the end of 1999, including those supplied by
vendors, or they will be retired. The cost to remediate possible exposures
resulting from the Year 2000 problem cannot be distinguished from the overall
cost of the ERP which approximated $3.0 million as of the end of 1998. Costs to
remediate Year 2000 exposures other than costs incurred in connection with the
ERP are not material.

The Company communicated 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 has also
communicated with its large customers 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 believes it has no exposure to
contingencies related to the Year 2000 issue for the products it has sold.




The Company has also communicated with the vendors supplying manufacturing
equipment utilizing hardware, software and associated embedded computer chips
and has determined that the majority of its equipment is Year 2000 compliant.
The remaining equipment not currently Year 2000 compliant will be compliant by
January 1 or retired.

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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. The Company believes
that the successful implementation of the ERP supporting the Company's North
American operations in 1998 has substantially mitigated the most pervasive risks
to the Company resulting from Year 2000 related computer failures. 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 has developed a contingency plan to address exposures to its
business resulting from possible Year 2000 problems. Because its core systems
have been made Year 2000 compliant already, the Company's contingency plan
primarily addresses identifying alternate sources for key materials and supplies
in the event that the Company's primary vendors are not able to supply the
Company in a timely fashion. For most such materials and supplies, alternate
sources have already been identified. The Company believes that, with the recent
implementation of the 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

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




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AMTROL INC. AND SUBSIDIARIES
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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:    August 13, 1999                  By: /s/ Albert D. Indelicato
    ------------------------------           ----------------------------------
                                               Albert D. Indelicato
                                               President,
                                               Chief Executive Officer and
                                               Director



Date:    August 13, 1999                  By: /s/ Donald W. Reilly
    ------------------------------           ----------------------------------
                                               Donald W. Reilly,
                                               Vice President,
                                               Chief Financial Officer and
                                               Treasurer






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