-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 AuvXtcGbSjvVbgqUPcWCp3cOmrOFraPFjypFeDDYmrwspWkkTMW4Detq+y0qU4hL
 hubVJVJ3bOqqjff3KJp9yQ==

<SEC-DOCUMENT>0000930413-06-007368.txt : 20061020
<SEC-HEADER>0000930413-06-007368.hdr.sgml : 20061020
<ACCEPTANCE-DATETIME>20061020123848
ACCESSION NUMBER:		0000930413-06-007368
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20061018
FILED AS OF DATE:		20061020
DATE AS OF CHANGE:		20061020

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			THERMODYNETICS INC
		CENTRAL INDEX KEY:			0000351902
		STANDARD INDUSTRIAL CLASSIFICATION:	MISCELLANEOUS FABRICATED METAL PRODUCTS [3490]
		IRS NUMBER:				061042505
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0331

	BUSINESS ADDRESS:	
		STREET 1:		651 DAY HILL RD
		STREET 2:		.
		CITY:			WINDSOR
		STATE:			CT
		ZIP:			06095
		BUSINESS PHONE:		2036832005

	MAIL ADDRESS:	
		STREET 1:		651 DAY HILL ROAD
		STREET 2:		.
		CITY:			WINDSOR
		STATE:			CT
		ZIP:			06095

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	THERMO KINETICS INC
		DATE OF NAME CHANGE:	19810607

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LERMAN ROBERT A
		CENTRAL INDEX KEY:			0000924119
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-10707
		FILM NUMBER:		061154873

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		8606832005

	MAIL ADDRESS:	
		STREET 1:		C/O THERMODYNETICS INC
		STREET 2:		651 DAY HILL ROAD
		CITY:			WINDSOR
		STATE:			CT
		ZIP:			06095
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>c44831_ex.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-10-18</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000351902</issuerCik>
        <issuerName>THERMODYNETICS INC</issuerName>
        <issuerTradingSymbol>TDYT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000924119</rptOwnerCik>
            <rptOwnerName>LERMAN ROBERT A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O THERMODYNETICS INC</rptOwnerStreet1>
            <rptOwnerStreet2>651 DAY HILL ROAD</rptOwnerStreet2>
            <rptOwnerCity>WINDSOR</rptOwnerCity>
            <rptOwnerState>CT</rptOwnerState>
            <rptOwnerZipCode>06095</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>1</isOther>
            <officerTitle>President</officerTitle>
            <otherText>Trustee of 401k Plan of Issuer</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, $.01 par value</value>
            </securityTitle>
            <transactionDate>
                <value>2006-10-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>8000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>2.80</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>996267</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, $.01 par value</value>
            </securityTitle>
            <transactionDate>
                <value>2006-10-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>7500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>2.90</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>988767</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock, $.01 par value</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>40905</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Wife</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock, $.01 par value</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>45289</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Wife</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Reporting Person sold all of the shares reported on this Form pursuant to that certain Agreement to Establish a Rule 10b5-1
 Selling Plan dated July 5, 2006.</footnote>
        <footnote id="F2">Reporting Person disclaims any beneficial ownership in such shares and this filing is not an admission of any claim of
 ownership or of any pecuniary interest in such shares.</footnote>
        <footnote id="F3">Shares held in trust under the 401(k) Plan for the Reporting Person's personal 401(k) account.  Excludes the aggregate
 401,551 shares held in trust by the trustees of the 401(k) Plan for all of the participating employees of the issuer.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Robert A. Lerman</signatureName>
        <signatureDate>2006-10-18</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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