Exhibit 10.2

                                 PROMISSORY NOTE


$900,000.00
                                                               December 21, 2006

Thermodynetics, Inc.
651 Day Hill Road
Windsor, Connecticut  06095
(Hereinafter referred to as "Borrower")

Wachovia Bank, National Association
5 Research Drive
Shelton, Connecticut  06904
(Hereinafter referred to as "Bank")

Borrower  promises  to pay to the order of Bank,  in lawful  money of the United
States of  America,  at its office  indicated  above or  wherever  else Bank may
specify,  the sum of Nine Hundred  Thousand and No/100 Dollars  ($900,000.00) or
such sum as may be advanced and outstanding  from time to time, with interest on
the  unpaid  principal  balance  at the rate and on the terms  provided  in this
Promissory Note  (including all renewals,  extensions or  modifications  hereof,
this "Note").

LOAN  AGREEMENT.  This Note is subject to the  provisions  of that  certain Loan
Agreement between Bank and Borrower of even date herewith, as modified from time
to time.

USE OF PROCEEDS.  Borrower  shall use the  proceeds of the loan(s)  evidenced by
this Note for the  commercial  purposes of  Borrower,  as follows:  refinance of
existing debt.

SECURITY.  Borrower  has  granted  Bank a security  interest  in the  collateral
described  in the  Loan  Documents,  including,  but not  limited  to,  real and
personal  property  collateral  described in that certain Open-End  Mortgage and
Security Agreement of even date herewith.

INTEREST  RATE.  Interest shall accrue on the unpaid  principal  balance of this
Note from the date hereof at the LIBOR Market Index Rate plus 1.5%, as that rate
may change from day to day in accordance  with changes in the LIBOR Market Index
Rate ("Interest  Rate").  "LIBOR Market Index Rate", for any day, means the rate
for 1 month U.S.  dollar  deposits as reported on Telerate page 3750 as of 11:00
a.m.,  London time,  on such day, or if such day is not a London  business  day,
then the immediately preceding London business day (or if not so reported,  then
as determined by Bank from another recognized source or interbank quotation).

ELECTION OF FIXED RATE.  Provided  Borrower is not in default under the terms of
this  Note,  Borrower  shall  have the  option  (the  "Fixed  Rate  Option")  of
converting the interest rate payable by Borrower from the floating interest rate
based upon the LIBOR  Market  Index Rate as provided  above to a fixed  interest
rate  determined as set forth herein.  The Fixed Rate Option may be exercised by
Borrower  at any one time  during the term of this Note by written  notice  (the
"Option  Notice")  to the  Bank at  least  forty-five  (45)  days  prior  to the
requested  effective date of the fixed interest rate,  which effective date (the
"Fixed Rate Adjustment Date") must be the first day of a calendar month and must
occur  following  the end of any LIBOR  Interest  Period  then in  effect.  Once
Borrower has exercised the Fixed Rate Option,  Borrower  shall have no option to
return to the floating interest rates provided herein above.

If Borrower  exercises the Fixed Rate Option then effective as of the Fixed Rate
Adjustment  Date, the interest rate payable on the unpaid  principal  balance of
this Note shall be fixed at an annual interest rate equal to the Bank's "Cost of
Funds" (as hereinafter defined) of borrowings, as of the Fixed Rate



<PAGE>

Adjustment  Date,  for a term  co-terminus  with the period  from the Fixed Rate
Adjustment Date to the Maturity Date,  plus 150 basis points.  The interest rate
which goes into effect on the Fixed Rate  Adjustment Date shall remain in effect
until the  Maturity  Date.  The term  "Cost of Funds"  means a per annum rate of
interest  which the Bank  discloses  to the  Borrower  as its  internal  cost of
borrowing funds for the applicable period and is not a published index available
to the general public.

DEFAULT  RATE.  In addition to all other  rights  contained  in this Note,  if a
Default  (as  defined  herein)  occurs and as long as a Default  continues,  all
outstanding  Obligations,  other than Obligations  under any swap agreements (as
defined in 11 U.S.C.  ss. 101, as in effect from time to time) between  Borrower
and Bank or its  affiliates,  shall bear  interest at the Interest  Rate plus 3%
("Default Rate").  The Default Rate shall also apply from acceleration until the
Obligations or any judgment thereon is paid in full.

INTEREST AND FEE(S) COMPUTATION  (ACTUAL/360).  Interest and fees, if any, shall
be computed on the basis of a 360-day year for the actual  number of days in the
applicable  period  ("Actual/360   Computation").   The  Actual/360  Computation
determines the annual  effective  interest yield by taking the stated  (nominal)
rate for a year's  period and then  dividing  said rate by 360 to determine  the
daily  periodic  rate to be  applied  for  each  day in the  applicable  period.
Application of the Actual/360  Computation produces an annualized effective rate
exceeding the nominal rate.

REPAYMENT  TERMS.  This Note  shall be due and  payable in  consecutive  monthly
payments of principal  equal to $3,750.00 plus accrued  interest,  commencing on
January 21, 2007 and continuing on the same day of each month  thereafter  until
fully paid. In any event,  all principal and accrued  interest  shall be due and
payable on December 21, 2016 (the "Maturity Date").

AUTOMATIC DEBIT OF CHECKING ACCOUNT FOR LOAN PAYMENT.  Borrower  authorizes Bank
to debit demand deposit account number xxxxxxxxxx or any other account with Bank
(routing  number  xxxxxxxxxxx)  designated  in  writing by  Borrower,  beginning
January  21,  2007 for any  payments  due  under  this  Note.  Borrower  further
certifies  that  Borrower  holds  legitimate   ownership  of  this  account  and
preauthorizes this periodic debit as part of its right under said ownership.

APPLICATION OF PAYMENTS. Monies received by Bank from any source for application
toward payment of the Obligations  shall be applied to accrued interest and then
to principal.  If a Default occurs,  monies may be applied to the Obligations in
any manner or order deemed appropriate by Bank.

If any  payment  received  by Bank under this Note or other  Loan  Documents  is
rescinded,  avoided or for any reason  returned  by Bank  because of any adverse
claim or threatened  action,  the returned  payment  shall remain  payable as an
obligation  of all persons  liable  under this Note or other Loan  Documents  as
though such payment had not been made.

DEFINITIONS. LOAN DOCUMENTS. The term "Loan Documents", as used in this Note and
the other Loan Documents, refers to all documents executed in connection with or
related to the loan  evidenced  by this Note and any prior notes which  evidence
all or any portion of the loan evidenced by this Note, and any letters of credit
issued  pursuant  to any loan  agreement  to which  this  Note is  subject,  any
applications  for such  letters of credit and any other  documents  executed  in
connection therewith or related thereto, and may include,  without limitation, a
commitment letter that survives closing, a loan agreement,  this Note,  guaranty
agreements,  security agreements,  security  instruments,  financing statements,
mortgage  instruments,  any  renewals  or  modifications,  whenever  any  of the
foregoing are executed,  but does not include swap  agreements (as defined in 11
U.S.C.  ss.  101,  as in  effect  from  time to  time).  OBLIGATIONS.  The  term
"Obligations",  as used in this Note and the other Loan Documents, refers to any
and  all  indebtedness  and  other   obligations  under  this  Note,  all  other
obligations under any other Loan Document(s), and all obligations under any swap
agreements  (as  defined in 11 U.S.C.  ss.  101, as in effect from time to time)
between Borrower and Bank, or its affiliates,  whenever executed.  CERTAIN OTHER
TERMS.  All terms  that are used but not  otherwise  defined  in any of the Loan
Documents shall have the definitions provided in the Uniform Commercial Code.

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<PAGE>


LATE CHARGE.  If any payments  are not timely made,  Borrower  shall also pay to
Bank a late  charge  equal to 5% of each  payment  past due for 10 or more days.
This late charge shall not apply to payments due at maturity or by  acceleration
hereof,  unless such late  payment is in an amount not greater  than the highest
periodic payment due hereunder.

Acceptance by Bank of any late payment without an accompanying late charge shall
not be deemed a waiver of Bank's right to collect such late charge or to collect
a late charge for any subsequent late payment received.

If this Note is secured by  owner-occupied  residential  real  property  located
outside the state in which the office of Bank first shown above is located,  the
late charge laws of the state where the real  property is located shall apply to
this Note and the late charge shall be the highest amount  allowable  under such
laws.  If no amount is stated  thereunder,  the late charge  shall be 5% of each
payment past due for 10 or more days.

ATTORNEYS'  FEES AND OTHER  COLLECTION  COSTS.  Borrower shall pay all of Bank's
reasonable  expenses  actually  incurred  to  enforce  or  collect  any  of  the
Obligations including, without limitation, reasonable arbitration,  paralegals',
attorneys'  and  experts'  fees  and  expenses,  whether  incurred  without  the
commencement of a suit, in any trial, arbitration, or administrative proceeding,
or in any appellate or bankruptcy proceeding.

USURY. If at any time the effective interest rate under this Note would, but for
this  paragraph,  exceed the maximum  lawful rate,  the effective  interest rate
under this Note shall be the maximum  lawful  rate,  and any amount  received by
Bank in excess of such rate shall be applied to  principal  and then to fees and
expenses, or, if no such amounts are owing, returned to Borrower.

DEFAULT.  If any of the following occurs, a default  ("Default") under this Note
shall  exist:  NONPAYMENT;  NONPERFORMANCE.  The  failure  of timely  payment or
performance  of the  Obligations  or  Default  under this Note or any other Loan
Documents.  FALSE WARRANTY.  A warranty or representation made or deemed made in
the Loan  Documents or furnished  Bank in connection  with the loan evidenced by
this  Note  proves  materially  false,  or if of a  continuing  nature,  becomes
materially  false.  CROSS DEFAULT.  At Bank's option,  any default in payment or
performance of any obligation under any other loans,  contracts or agreements of
Borrower, any Subsidiary or Affiliate of Borrower, any general partner of or the
holder(s)  of the  majority  ownership  interests  of Borrower  with Bank or its
affiliates  ("Affiliate" shall have the meaning as defined in 11 U.S.C. ss. 101,
as in  effect  from  time to time,  except  that the  term  "Borrower"  shall be
substituted for the term "Debtor" therein;  "Subsidiary" shall mean any business
in which  Borrower  holds,  directly or  indirectly,  a  controlling  interest).
CESSATION;  BANKRUPTCY. The death of, appointment of a guardian for, dissolution
of, termination of existence of, loss of good standing status by, appointment of
a receiver for,  assignment for the benefit of creditors of, or  commencement of
any bankruptcy or insolvency proceeding by or against Borrower, its Subsidiaries
or  Affiliates,  if any,  or any  general  partner  of or the  holder(s)  of the
majority  ownership  interests of Borrower,  or any party to the Loan Documents.
MATERIAL CAPITAL STRUCTURE OR BUSINESS ALTERATION. Without prior written consent
of Bank, (i) a material alteration in the kind or type of Borrower's business or
that of  Borrower's  Subsidiaries  or  Affiliates,  if  any;  (ii)  the  sale of
substantially  all of the  business  or assets of  Borrower,  any of  Borrower's
Subsidiaries or Affiliates or any guarantor, or a material portion (10% or more)
of such  business  or assets if such a sale is outside  the  ordinary  course of
business of Borrower,  or any of  Borrower's  Subsidiaries  or Affiliates or any
guarantor,  or more than 50% of the  outstanding  stock or voting power of or in
any such entity in a single  transaction or a series of transactions;  (iii) the
acquisition of  substantially  all of the business or assets or more than 50% of
the  outstanding  stock or voting power of any other entity;  or (iv) should any
Borrower or any of Borrower's  Subsidiaries or Affiliates or any guarantor enter
into any merger or  CONSOLIDATION.  MATERIAL ADVERSE CHANGE.  Bank determines in
good faith, in its sole reasonable discretion, that the prospects for payment or
performance of the Obligations  are materially  impaired or there has occurred a
material  adverse change in the business or prospects of Borrower,  financial or
otherwise.

REMEDIES  UPON  DEFAULT.  If a  Default  occurs  under  this  Note  or any  Loan
Documents,  Bank may at any time thereafter,  take the following  actions:  BANK
LIEN. Foreclose its security interest or lien against


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<PAGE>

Borrower's deposit accounts and investment property without notice. ACCELERATION
UPON DEFAULT. Accelerate the maturity of this Note and, at Bank's option, any or
all other  Obligations,  other than  Obligations  under any swap  agreements (as
defined in 11 U.S.C.  ss. 101, as in effect from time to time) between  Borrower
and Bank, or its affiliates,  which shall be due in accordance with and governed
by the  provisions  of  said  swap  agreements;  whereupon  this  Note  and  the
accelerated Obligations shall be immediately due and payable; provided, however,
if the Default is based upon a bankruptcy or insolvency  proceeding commenced by
or against  Borrower or any guarantor or endorser of this Note, all  Obligations
(other than  Obligations  under any swap  agreement as  referenced  above) shall
automatically  and  immediately  be due and  payable.  CUMULATIVE.  Exercise any
rights and remedies as provided under the Note and other Loan  Documents,  or as
provided by law or equity.

FINANCIAL AND OTHER INFORMATION. Borrower shall deliver to Bank such information
as Bank may reasonably request from time to time,  including without limitation,
financial   statements  and  information   pertaining  to  Borrower's  financial
condition. Such information shall be true, complete, and accurate.

WAIVERS AND AMENDMENTS. No waivers, amendments or modifications of this Note and
other Loan  Documents  shall be valid unless in writing and signed by an officer
of Bank. No waiver by Bank of any Default shall operate as a waiver of any other
Default or the same  Default on a future  occasion.  Neither the failure nor any
delay on the part of Bank in exercising any right,  power,  or remedy under this
Note and other Loan  Documents  shall operate as a waiver  thereof,  nor shall a
single or  partial  exercise  thereof  preclude  any other or  further  exercise
thereof or the exercise of any other right, power or remedy.

Except to the extent  otherwise  provided by the Loan Documents or prohibited by
law,  each  Borrower  and each  other  person  liable  under  this  Note  waives
presentment,  protest,  notice  of  dishonor,  demand  for  payment,  notice  of
intention to accelerate maturity,  notice of acceleration of maturity, notice of
sale and all other notices of any kind.  Further,  each agrees that Bank may (i)
extend,  modify or renew this Note or make a novation of the loan  evidenced  by
this Note,  and/or (ii) grant releases,  compromises or indulgences with respect
to any  collateral  securing this Note, or with respect to any Borrower or other
person liable under this Note or any other Loan Documents, all without notice to
or consent of each  Borrower and other such person,  and without  affecting  the
liability of each Borrower and other such person; provided, Bank may not extend,
modify or renew this Note or make a novation of the loan  evidenced by this Note
without  the  consent of the  Borrower,  or if there is more than one  Borrower,
without the consent of at least one Borrower;  and further provided, if there is
more than one  Borrower,  Bank may not enter  into a  modification  of this Note
which increases the burdens of a Borrower without the consent of that Borrower.

MISCELLANEOUS  PROVISIONS.  ASSIGNMENT.  This Note and the other Loan  Documents
shall  inure to the  benefit  of and be  binding  upon  the  parties  and  their
respective  heirs,  legal  representatives,   successors  and  assigns.   Bank's
interests in and rights under this Note and the other Loan  Documents are freely
assignable,  in whole or in part, by Bank. In addition,  nothing in this Note or
any of the other Loan  Documents  shall prohibit Bank from pledging or assigning
this Note or any of the other  Loan  Documents  or any  interest  therein to any
Federal  Reserve  Bank.  Borrower  shall not  assign  its  rights  and  interest
hereunder without the prior written consent of Bank, and any attempt by Borrower
to assign without Bank's prior written  consent is null and void. Any assignment
shall not  release  Borrower  from the  Obligations.  APPLICABLE  LAW;  CONFLICT
BETWEEN  DOCUMENTS.  This Note and, unless otherwise  provided in any other Loan
Document,  the other Loan Documents shall be governed by and  interpreted  under
the laws of the state named in Bank's  address on the first page hereof  without
regard to that state's  conflict of laws  principles.  If the terms of this Note
should  conflict with the terms of any loan agreement or any  commitment  letter
that  survives  closing,  the  terms  of this  Note  shall  control.  BORROWER'S
ACCOUNTS.  Except as prohibited by law, Borrower grants Bank a security interest
in all of Borrower's  deposit  accounts and marketable  securities with Bank and
any of its affiliates.  SWAP  AGREEMENTS.  All swap agreements (as defined in 11
U.S.C.  ss. 101, as in effect from time to time), if any,  between  Borrower and
Bank or its  affiliates  are  independent  agreements  governed  by the  written
provisions of said swap agreements,  which will remain in full force and effect,
unaffected by any repayment,  prepayment,  acceleration,  reduction, increase or
change in the terms of this Note, except as otherwise expressly provided in said
written swap  agreements,  and any payoff  statement  from Bank relating to this
Note shall not apply to said swap


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<PAGE>

agreements  except as  otherwise  expressly  provided in such payoff  statement.
JURISDICTION. Borrower irrevocably agrees to non-exclusive personal jurisdiction
in  the  state  identified  as  the  Jurisdiction  above.  SEVERABILITY.  If any
provision of this Note or of the other Loan  Documents  shall be  prohibited  or
invalid under  applicable  law, such provision  shall be ineffective but only to
the extent of such prohibition or invalidity, without invalidating the remainder
of such  provision  or the  remaining  provisions  of this  Note or  other  such
document.  NOTICES.  Any notices to Borrower shall be sufficiently  given, if in
writing and mailed or delivered to the  Borrower's  address  shown above or such
other address as provided hereunder,  with a copy to Kenneth B. Lerman, P.C. 651
Day Hill Road, Windsor,  Connecticut 06095 and to Bank, if in writing and mailed
or delivered to Wachovia Bank, National Association, Mail Code VA7628, P. O. Box
13327,  Roanoke,  VA 24040 or Wachovia  Bank,  National  Association,  Mail Code
VA7628,  10 South Jefferson Street,  Roanoke,  VA 24011 or such other address as
Bank may specify in writing from time to time.  Notices to Bank must include the
mail code. In the event that  Borrower  changes  Borrower's  address at any time
prior to the date the Obligations are paid in full,  Borrower agrees to promptly
give written  notice of said change of address by registered or certified  mail,
return receipt requested,  all charges prepaid. PLURAL; CAPTIONS. All references
in the Loan Documents to Borrower, guarantor, person, document or other nouns of
reference  mean both the singular  and plural form,  as the case may be, and the
term  "person"  shall  mean any  individual,  person  or  entity.  The  captions
contained in the Loan Documents are inserted for convenience  only and shall not
affect the meaning or interpretation of the Loan Documents.  ADVANCES. Bank may,
in its sole discretion, make other advances which shall be deemed to be advances
under this Note,  even  though the stated  principal  amount of this Note may be
exceeded as a result thereof.  POSTING OF PAYMENTS. All payments received during
normal  banking  hours  after  2:00 p.m.  local time at the office of Bank first
shown above shall be deemed  received  at the opening of the next  banking  day.
JOINT  AND  SEVERAL  OBLIGATIONS.  If there is more than one  Borrower,  each is
jointly and severally  obligated  together with all other parties  obligated for
the  Obligations.  FEES AND TAXES.  Borrower shall promptly pay all documentary,
intangible recordation and/or similar taxes on this transaction whether assessed
at closing or arising  from time to time.  LIMITATION  ON  LIABILITY;  WAIVER OF
PUNITIVE  DAMAGES.  EACH OF THE PARTIES  HERETO,  INCLUDING  BANK BY  ACCEPTANCE
HEREOF, AGREES THAT IN ANY JUDICIAL,  MEDIATION OR ARBITRATION PROCEEDING OR ANY
CLAIM OR  CONTROVERSY  BETWEEN  OR AMONG THEM THAT MAY ARISE OUT OF OR BE IN ANY
WAY CONNECTED WITH THIS AGREEMENT,  THE LOAN DOCUMENTS OR ANY OTHER AGREEMENT OR
DOCUMENT  BETWEEN OR AMONG THEM OR THE OBLIGATIONS  EVIDENCED  HEREBY OR RELATED
HERETO,  IN NO EVENT SHALL ANY PARTY HAVE A REMEDY OF, OR BE LIABLE TO THE OTHER
FOR, (1) INDIRECT, SPECIAL OR CONSEQUENTIAL DAMAGES OR (2) PUNITIVE OR EXEMPLARY
DAMAGES.  EACH OF THE  PARTIES  HEREBY  EXPRESSLY  WAIVES  ANY RIGHT OR CLAIM TO
PUNITIVE OR EXEMPLARY  DAMAGES THEY MAY HAVE OR WHICH MAY ARISE IN THE FUTURE IN
CONNECTION WITH ANY SUCH PROCEEDING,  CLAIM OR CONTROVERSY,  WHETHER THE SAME IS
RESOLVED BY ARBITRATION, MEDIATION, JUDICIALLY OR OTHERWISE. PATRIOT ACT NOTICE.
To help fight the funding of terrorism and money laundering activities,  Federal
law  requires  all  financial   institutions  to  obtain,   verify,  and  record
information  that identifies  each person who opens an account.  For purposes of
this  section,  account  shall be  understood  to include loan  accounts.  FINAL
AGREEMENT.  This Note and the other Loan Documents represent the final agreement
between  the  parties  and  may  not  be  contradicted  by  evidence  of  prior,
contemporaneous  or  subsequent  oral  agreements  of the parties.  There are no
unwritten oral agreements between the parties.

WAIVER OF JURY  TRIAL.  TO THE  EXTENT  PERMITTED  BY  APPLICABLE  LAW,  EACH OF
BORROWER  BY  EXECUTION  HEREOF  AND  BANK  BY  ACCEPTANCE  HEREOF,   KNOWINGLY,
VOLUNTARILY AND INTENTIONALLY  WAIVES ANY RIGHT EACH MAY HAVE TO A TRIAL BY JURY
IN RESPECT OF ANY LITIGATION BASED ON, OR ARISING OUT OF, UNDER OR IN CONNECTION
WITH THIS NOTE, THE LOAN DOCUMENTS OR ANY AGREEMENT  CONTEMPLATED TO BE EXECUTED
IN  CONNECTION  WITH THIS NOTE,  OR ANY COURSE OF  CONDUCT,  COURSE OF  DEALING,
STATEMENTS  (WHETHER  VERBAL OR  WRITTEN)  OR ACTIONS OF ANY PARTY WITH  RESPECT
HERETO.  THIS  PROVISION IS A MATERIAL  INDUCEMENT  TO BANK TO ACCEPT THIS NOTE.
EACH OF THE PARTIES AGREES THAT THE TERMS HEREOF SHALL SUPERSEDE AND REPLACE ANY
PRIOR AGREEMENT RELATED TO ARBITRATION OF DISPUTES BETWEEN THE PARTIES CONTAINED
IN ANY LOAN DOCUMENT OR ANY OTHER DOCUMENT OR AGREEMENT


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<PAGE>

HERETOFORE   EXECUTED  IN  CONNECTION  WITH,   RELATED  TO  OR  BEING  REPLACED,
SUPPLEMENTED, EXTENDED OR MODIFIED BY, THIS NOTE.

CONNECTICUT  PREJUDGMENT  REMEDY  WAIVER.  EACH BORROWER  ACKNOWLEDGES  THAT THE
TRANSACTIONS  REPRESENTED  BY THIS NOTE ARE COMMERCIAL  TRANSACTIONS  AND HEREBY
VOLUNTARILY  AND  KNOWINGLY  WAIVES  ANY  RIGHTS  TO NOTICE  OF AND  HEARING  ON
PREJUDGMENT  REMEDIES UNDER CHAPTER 903A OF THE CONNECTICUT  GENERAL STATUTES OR
OTHER  STATUTES  AFFECTING  PREJUDGMENT  REMEDIES,  AND  AUTHORIZES  THE  BANK'S
ATTORNEY TO ISSUE A WRIT FOR A PREJUDGMENT REMEDY WITHOUT COURT ORDER,  PROVIDED
THE COMPLAINT SHALL SET FORTH A COPY OF THIS WAIVER.

IN WITNESS  WHEREOF,  Borrower,  on the day and year first  above  written,  has
caused this Note to be duly executed under seal.

                                    Thermodynetics, Inc.


                                    By: /s/ JOHN F. FERRARO            (SEAL)
                                        -----------------------------
                                            John F. Ferraro, Chairman


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