Exhibit

We refer to the Registration Statement on Form S-3 (the “Registration Statement”) being filed by Thermon Group Holdings, Inc., a Delaware corporation (the “Company”), with the Securities and Exchange Commission (the “SEC”) under the Securities Act of 1933, as amended (the “Securities Act”), relating to the registration of (i) common stock, par value $0.001 per share, of the Company (“Common Stock”), (ii) preferred stock, par value $0.001 per share, of the Company (the “Preferred Stock”), (iii) debt securities of the Company (the “Debt Securities”), which may be secured or unsecured, senior, subordinated or junior subordinated and issued in one or more series, (iv) warrants to purchase Common Stock, Preferred Stock or Debt Securities (the “Warrants”), (v) stock purchase contracts (the “Stock Purchase Contracts”), entitling or obligating the holders thereof to purchase from or sell to the Company and the Company to sell to or purchase from the holders thereof, Common Stock or Preferred Stock at a future date or dates, and (vi) stock purchase units, each representing ownership of a Stock Purchase Contract and Debt Securities or debt obligations of another issuer securing the holder’s obligation to purchase Common Stock or Preferred Stock, as applicable, under the Stock Purchase Contract (the “Stock Purchase Units” and, together with the Common Stock, Preferred Stock, Debt Securities, Warrants and Stock Purchase Contracts, the “Securities”), such Securities in an aggregate amount not to exceed an initial offering price of $250,000,000, in each case as described in the prospectus which forms a part of the Registration Statement, as amended or supplemented from time to time.

Unless otherwise specified in the applicable prospectus supplement, (i) the Preferred Stock will be issued in one or more series and the relative powers, designations, preferences, privileges, rights and qualifications, limitations or restrictions of such Preferred Stock will be set forth in one or more certificates of designation (each, a “Certificate of Designation”), (ii) the Debt Securities will be issued under one or more indentures (each, an “Indenture”) to be entered into between the Company and one or more trustees (each, a “Trustee”), (iii) the Warrants will be issued under one or more warrant agreements (each, a “Warrant Agreement”) to be entered into between the Company and a warrant agent (the “Warrant Agent”), (iv) the Stock Purchase Contracts will be issued under one or more stock purchase contract agreements (each, a “Stock Purchase Contract Agreement”) to be entered into between the Company and a stock purchase contract agent (the “Stock Purchase Contract Agent”), and (v) the Stock Purchase Units will be issued pursuant to one or more stock purchase unit agreements (each, a “Stock Purchase Unit Agreement”) to be entered into between the Company and the stock purchase unit agent party thereto. Each Indenture (to the extent not already filed as an exhibit to the Registration Statement), Certificate of Designation, Warrant Agreement, Stock Purchase Contract Agreement and Stock Purchase Unit Agreement, as applicable, will be in a form to be filed as an exhibit to a post-effective amendment to the Registration Statement or a document filed under the Securities Exchange Act of 1934, as amended, and incorporated as an exhibit to the Registration Statement by reference. We refer to the Indenture(s), any series of Debt Securities, any supplemental indenture or officers’ certificate establishing the form or terms of the Debt Securities of any series, any Warrant Agreement, any issue of Warrants, any Stock Purchase Contract Agreement and any Stock Purchase Unit Agreement collectively as the “Opinion Documents.”

We have examined the Registration Statement, the exhibits thereto, the Second Amended and Restated Certificate of Incorporation of the Company (the “Charter”) currently in effect, the Second Amended and Restated Bylaws of the Company (the “Bylaws”) currently in effect, and the resolutions (the “Resolutions”) adopted by the board of directors of the Company (the “Board”) on May 18, 2017 relating to the Registration Statement. We have also examined originals, or copies of originals certified to our satisfaction, of such agreements, documents, certificates and statements of the Company and others, and have examined such questions of law, as we have considered relevant and necessary as a basis for this opinion letter. We have assumed the authenticity of all documents submitted to us as originals, the genuineness of all signatures, the legal capacity of all persons and the conformity with the original documents of any copies thereof submitted to us for examination. As to facts relevant to the opinions expressed herein, we have relied without independent investigation or verification upon, and assumed the accuracy and completeness of, certificates, letters and oral and written statements and representations of public officials and officers and other representatives of the Company.

1. With respect to an offering of shares of Common Stock covered by the Registration Statement, such shares of Common Stock will be validly issued, fully paid and non-assessable when: (i) the Registration Statement, as finally amended (including any necessary post-effective amendments), shall have become effective under the Securities Act; (ii) a prospectus supplement with respect to the sale of such shares of Common Stock shall have been filed with the SEC in compliance with the Securities Act and the rules and regulations thereunder; (iii) the Board or a duly authorized committee thereof shall have duly adopted final resolutions in conformity with the Charter, the Bylaws and the Resolutions authorizing the issuance and sale of such shares of Common Stock; and (iv) certificates representing such shares of Common Stock shall have been duly executed, countersigned and registered and duly delivered in accordance with the applicable definitive purchase, underwriting or similar agreement to the purchasers thereof against payment of the agreed consideration therefor in an amount not less than the aggregate par value thereof.

2. The issuance and sale of each series of Preferred Stock covered by the Registration Statement will be duly authorized, and each share of such series of Preferred Stock will be validly issued, fully paid and non-assessable, when: (i) the Registration Statement, as finally amended (including any necessary post-effective amendments), shall have become effective under the Securities Act; (ii) a prospectus supplement with respect to the sale of such series of Preferred Stock shall have been filed with the SEC in compliance with the Securities Act and the rules and regulations thereunder; (iii) the Board or a duly authorized committee thereof shall have duly adopted final resolutions in conformity with the Charter, the Bylaws and the Resolutions establishing the designations, preferences, rights, qualifications, limitations or restrictions of such series of Preferred Stock and authorizing the issuance and sale of such series of Preferred Stock; (iv) the Company shall have filed with the Secretary of State of the State of Delaware a Certificate of Designation with respect to such series of Preferred Stock in accordance with the General Corporation Law of the State of Delaware (the “DGCL”) and in conformity with the Charter and such final resolutions; and (v) certificates representing such series of Preferred Stock shall have been duly executed, countersigned and registered and duly delivered in accordance with the applicable definitive purchase, underwriting or similar agreement to the purchasers thereof against payment of the agreed consideration therefor in an amount not less than the aggregate par value thereof.

3. The Debt Securities of each series covered by the Registration Statement will constitute valid and binding obligations of the Company when: (i) the Registration Statement, as finally amended (including any necessary post-effective amendments), shall have become effective under the Securities Act and the Indenture under which such series of Debt Securities is being issued (including any necessary supplemental indenture) shall have been qualified under the Trust Indenture Act of 1939, as amended; (ii) a prospectus supplement with respect to such series of Debt Securities shall have been filed with the SEC in compliance with the Securities Act and the rules and regulations thereunder; (iii) the Indenture, substantially in the form filed as an exhibit to the Registration Statement, shall have been duly authorized, executed and delivered by the Company and the Trustee; (iv) all necessary corporate action shall have been taken by the Company to authorize the form, terms, execution, delivery, performance, issuance and sale of such series of Debt Securities as contemplated by the Registration Statement, the prospectus supplement relating to such series of Debt Securities and the Indenture and to authorize the execution, delivery and performance of a supplemental indenture or officers’ certificate establishing the form and terms of such series of Debt Securities as contemplated by the Indenture; (v) a supplemental indenture or officers’ certificate establishing the form and terms of such series of Debt Securities shall have been duly executed and delivered by the Company and the Trustee (in the case of such a supplemental indenture) or by duly authorized officers of the Company (in the case of such an officers’ certificate), in each case in accordance with the provisions of the Charter, Bylaws, final resolutions of the Board or a duly authorized committee thereof and the Indenture; and (vi) the certificates evidencing the Debt Securities of such series shall have been duly executed and delivered by the Company, authenticated by the Trustee and issued, all in accordance with the Charter, the Bylaws, the Resolutions, final resolutions of the Board or a duly authorized committee thereof, the Indenture and

4. Each issue of Warrants covered by the Registration Statement will constitute valid and binding obligations of the Company when: (i) the Registration Statement, as finally amended (including any necessary post-effective amendments), shall have become effective under the Securities Act; (ii) a prospectus supplement with respect to such issue of Warrants and the Common Stock, Debt Securities or Preferred Stock issuable upon exercise of such Warrants shall have been filed with the SEC in compliance with the Securities Act and the rules and regulations thereunder; (iii) a Warrant Agreement relating to such issue of Warrants shall have been duly authorized, executed and delivered by the Company and duly executed and delivered by the warrant agent named in the Warrant Agreement; (iv) the Board or a duly authorized committee thereof shall have duly adopted final resolutions in conformity with the Charter, the Bylaws and the Resolutions authorizing the execution and delivery of the Warrant Agreement and the issuance and sale of such issue of Warrants; (v) if such Warrants are exercisable for Common Stock, the actions described in paragraph 1 above shall have been taken; (vi) if such Warrants are exercisable for Preferred Stock, the actions described in paragraph 2 above shall have been taken; (vii) if such Warrants are exercisable for Debt Securities, the actions described in paragraph 3 above shall have been taken; and (viii) certificates representing such issue of Warrants shall have been duly executed, countersigned and issued in accordance with such Warrant Agreement and shall have been duly delivered in accordance with the applicable definitive purchase, underwriting or similar agreement to the purchasers thereof against payment of the agreed consideration therefor.

5. The Stock Purchase Contracts will constitute valid and binding obligations of the Company when: (i) the Registration Statement, as finally amended (including any necessary post-effective amendments), shall have become effective under the Securities Act; (ii) a prospectus supplement with respect to such Stock Purchase Contracts shall have been filed with the SEC in compliance with the Securities Act and the rules and regulations thereunder; (iii) a Stock Purchase Contract Agreement relating to such Stock Purchase Contracts shall have been duly authorized, executed and delivered by the Company and duly executed and delivered by the Stock Purchase Contract Agent named in the Stock Purchase Contract Agreement; (iv) the Board or a duly authorized committee thereof shall have duly adopted final resolutions in conformity with the Charter, the Bylaws and the Resolutions authorizing the execution, delivery, issuance and sale of such Stock Purchase Contracts; (v) if such Stock Purchase Contracts relate to the issuance and sale of Common Stock, the actions described in paragraph 1 above shall have been taken; (vi) if such Stock Purchase Contracts relate to the issuance and sale of Preferred Stock, the actions described in paragraph 2 above shall have been taken; and (vii) certificates representing such Stock Purchase Contracts shall have been duly executed, countersigned and registered in accordance with the Stock Purchase Contract Agreement and shall have been duly delivered to the purchasers thereof in accordance with the Stock Purchase Contract Agreement against payment of the agreed consideration therefor.

6. The Stock Purchase Units will constitute valid and binding obligations of the Company when: (i) the Registration Statement, as finally amended (including any necessary post-effective amendments), shall have become effective under the Securities Act; (ii) a prospectus supplement with respect to such Stock Purchase Units shall have been filed with the SEC in compliance with the Securities Act and the rules and regulations thereunder; (iii) the Board or a duly authorized committee thereof shall have duly adopted final resolutions in conformity with the Charter, the Bylaws and the Resolutions authorizing the execution, delivery, issuance and sale of such Stock Purchase Units; (iv) the actions described in paragraphs 3 and 5 above shall have been taken; and (v) certificates representing such Stock Purchase Units shall have been duly executed, countersigned and registered and shall have been duly delivered to the purchasers thereof in accordance with the applicable definitive purchase, underwriting or similar agreement against payment of the agreed consideration therefor.

Our opinions are subject to bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance, fraudulent transfer and other similar laws relating to or affecting creditors’ rights generally and to general equitable principles (regardless of whether considered in a proceeding in equity or at law), including concepts of commercial reasonableness, good faith and fair dealing and the possible unavailability of specific performance or injunctive relief. Our opinions are also subject to (i) provisions of law which may require that a judgment for money damages rendered by a court in the United States of America be expressed only in United States dollars, (ii) requirements that a claim with respect to any Debt Securities or other obligations that are denominated or payable other than in United States dollars (or a judgment denominated or payable other than in United States dollars in respect of such claim) be converted into United States dollars at a rate of exchange prevailing on a date determined pursuant to applicable law and (iii) governmental authority to limit, delay or prohibit the making of payments outside of the United States of America or in a foreign currency.

Documents and all actions necessary for the issuance, sale and delivery of the applicable Securities will not (A) contravene or violate the Charter, Bylaws, the Resolutions or any other applicable final resolutions adopted by the Board or any duly authorized committee thereof, (B) violate any law, rule or regulation applicable to the Company, (C) result in a default under or breach of any agreement or instrument binding upon the Company or any order, judgment or decree of any court or governmental authority applicable to the Company, or (D) require any authorization, approval or other action by, or notice to or filing with, any court or governmental authority (other than such authorizations, approvals, actions, notices or filings which shall have been obtained or made, as the case may be, and which shall be in full force and effect); (iii) the authorization thereof by the Company, as the case may be, will not have been modified or rescinded, and there will not have occurred any change in law affecting the validity, legally binding character or enforceability thereof; (iv) the Charter and the Bylaws, each as currently in effect, will not have been modified or amended and will be in full force and effect; and (v) in the case of the issue of Warrants, Stock Purchase Contracts or Stock Purchase Units, the terms and conditions of such Security, the underlying Security, if any, and any related Warrant Agreement, Stock Purchase Contract Agreement and/or Stock Purchase Unit Agreement will be as expressly contemplated in the prospectus supplement relating thereto.

With respect to each Opinion Document and other instrument or agreement referred to in or otherwise relevant to the opinions set forth herein (each, an “Instrument”), we have assumed, to the extent relevant to the opinions set forth herein, that (i) each party to such Instrument (if not a natural person) was duly organized or formed, as the case may be, and was at all relevant times and is validly existing and in good standing under the laws of its jurisdiction of organization or formation, as the case may be, and had at all relevant times and has full right, power and authority to execute, deliver and perform its obligations under such Instrument; (ii) such Instrument has been duly authorized, executed and delivered by each party thereto; and (iii) such Instrument was at all relevant times and is a valid, binding and enforceable agreement or obligation, as the case may be, of, each party thereto.



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