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                                                                    EXHIBIT 31.2

                                 CERTIFICATIONS

I, Larry T. Guillemette, certify that:

      1.    I have reviewed this quarterly report on Form 10-Q of AMTROL Inc;

      2.    Based on my knowledge, this quarterly report does not contain any
            untrue statement of a material fact or omit to state a material fact
            necessary to make the statements made, in light of the circumstances
            under which such statements were made, not misleading with respect
            to the period covered by this quarterly report;

      3.    Based on my knowledge, the financial statements, and other financial
            information included in this quarterly report, fairly present in all
            material respects the financial condition, results of operations and
            cash flows of the Registrant as of, and for, the periods presented
            in this quarterly report;

      4.    The Registrant's other certifying officers and I are responsible for
            establishing and maintaining disclosure controls and procedures (as
            defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the
            Registrant and have:

              a.    Designed such disclosure controls and procedures, or caused
                    such disclosure controls and procedures to be designed under
                    our supervision, to ensure that material information
                    relating to the Registrant, including its consolidated
                    subsidiaries, is made known to us by others within those
                    entities, particularly during the period in which this
                    quarterly report is being prepared;

              b.    (Paragraph omitted in accordance with SEC transition
                    instructions contained in SEC Release 34-47986)

              c.    Evaluated the effectiveness of the Registrant's disclosure
                    controls and procedures and presented in this report our
                    conclusions about the effectiveness of the disclosure
                    controls and procedures, as of the end of the period covered
                    by this quarterly report based on such evaluation; and

              d.    Disclosed in this quarterly report any change in the
                    Registrant's internal control over financial reporting that
                    occurred during the Registrant's most recent fiscal quarter
                    (the Registrant's fourth fiscal quarter in the case of an
                    annual report) that has materially affected, or is
                    reasonably likely to materially affect, the Registrant's
                    internal control over financial reporting; and

      5.    The Registrant's other certifying officers and I have disclosed,
            based on our most recent evaluation of internal control over
            financial reporting, to the Registrant's auditors and the audit
            committee of the Registrant's Board of Directors (or persons
            performing the equivalent functions):

              a.    All significant deficiencies and material weaknesses in the
                    design or operation of internals control over financial
                    reporting which are reasonably likely to adversely affect
                    the Registrant's ability to record, process, summarize and
                    report financial information; and

              b.    Any fraud, whether or not material, that involves management
                    or other employees who have a significant role in the
                    Registrant's internal control over financial reporting.

Date: November 5, 2004                           By: /s/ LARRY T. GUILLEMETTE
                                                     ---------------------------
                                                     Larry T. Guillemette
                                                     Executive Vice President,
                                                     Chief Financial Officer and
                                                     Treasurer