EXHIBIT 31(B)

                                  CERTIFICATION
   PURSUANT TO RULES 13A-15 AND 15D-15 OF THE SECURITIES EXCHANGE ACT OF 1934


I, ROBERT I. LIEBERMAN, Chief Financial Officer of Thermodynetics, Inc., certify
that:

1. I have reviewed this quarterly report on Form 10-QSB of THERMODYNETICS, INC.;

2. Based on my knowledge, this 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 report;

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

4. The Company's other certifying officer 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)) and internal control over financial reporting (as
defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the Company and have:

         a) designed such disclosure controls and procedures to provide that
         material information relating to the Company, including its
         consolidated subsidiaries, is made known to us by others within those
         entities, particularly during the period in which this report is being
         prepared;

         b) designed such internal control over financial reporting, or caused
         such internal control over financial reporting to be designed under our
         supervision, to provide reasonable assurance regarding the reliability
         of financial reporting and the preparation of financial statements for
         external purposes in accordance with generally accepted accounting
         principles;

         c) evaluated the overall effectiveness of the Company's disclosure
         controls and procedures to provide material information relating to the
         registrant, as of the end of the period covered by this report based on
         such evaluation; and

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

5. The Company's other certifying officer and I have disclosed, based on our
knowledge and our most recent evaluation of internal control over financial
reporting, to the Company's auditors and the audit committee of the Company's
Board of Directors:

         a) all significant deficiencies and material weaknesses in the design
         or operation of internal control over financial reporting which are
         reasonably likely to adversely affect the Company'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 Company's internal
         controls over financial reporting.

         Date: February 13, 2006       BY:   /s/  ROBERT I. LIEBERMAN
                                           -------------------------------------
                                           Robert I. Lieberman
                                           Treasurer and Chief Financial Officer



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