**Exhibit10.12**

**FOURTH AMENDMENT TO REVOLVING CREDIT,**

**TERM LOAN AND SECURITY AGREEMENT**

 

This **FOURTH AMENDMENT TO REVOLVING CREDIT, TERM LOAN ANDSECURITY AGREEMENT** (this “Amendment”) is made and entered into this22nd day of April, 2002 and is to be effective as of February 28, 2002, by andamong **AAF-MCQUAY INC**., a Delawarecorporation “Borrower”); the various financial institutions listed on thesignature pages hereof and their respective successors and permitted assignswhich become “Lenders”; and **PNC BANK,NATIONAL ASSOCIATION**, a national association (“PNC”), as collateraland administrative agent for Lenders (PNC, together with its successors in suchcapacity, the “Agent”).

 

**Recitals:**

 

Agent, Lendersand Borrower are parties to a certain Revolving Credit, Term Loan and SecurityAgreement dated September 30, 1999 (as at any time amended, the “CreditAgreement”) pursuant to which Lenders have made certain revolving credit andterm loans to Borrower.

 

The partiesdesire to amend the Credit Agreement as hereinafter set forth.

 

NOW,THEREFORE, for TEN DOLLARS ($10 .00) in hand paid and other good and valuableconsideration, the receipt and sufficiency of which are hereby severallyacknowledged, the parties hereto, intending to be legally bound hereby, agreeas follows:

 

**1.             Definitions**.  All capitalized terms used in thisAmendment, unless otherwise defined herein, shall have the meaning ascribed tosuch terms in the Credit Agreement.

 

**2.             Amendmentsto Credit Agreement**.  The Credit Agreement is hereby amended by deleting the Section6.7 in its entirety and inserting the following in lieu thereof:

 

**6.7  ConsolidatedTotal Assets**. Maintain, at all times, Consolidated Total Assets of at least$560,000,000.

 

**3.             Consentto Prepayment of Indebtedness**.  Notwithstanding the provisions of Section7.17 of the Credit Agreement, the Lenders hereby consent to Borrower prepayingup to $1.045,000 of the Indebtedness evidenced by the $3,300,000 City ofPlymouth, Minnesota Industrial Development Revenue Bonds (McQuay-Perfex Project)Series 1979.

 

----

 

**4.             Ratificationand Reaffirmation**.  Borrower hereby ratifies and reaffirms the Obligations, each ofthe Loan Documents and all of Borrower’s covenants, duties, indebtedness andliabilities under the Loan Documents.

 

**5.             Acknowledgmentsand Stipulations**. Borrower acknowledges and stipulates that the Credit Agreement and theother Loan Documents executed by Borrower are legal, valid and bindingobligations of Borrower that are enforceable against Borrower in accordancewith the terms thereof; all of the Obligations are owing and payable withoutdefense, offset or counterclaim (and to the extent there exists any suchdefense, offset or counterclaim on the date hereof, the same is hereby waivedby Borrower); the security interests and liens granted by Borrower in favor ofLender are duly perfected, first priority security interests and liens; theunpaid principal amount of the Revolving A Advances on and as of the opening ofbusiness on April 17, 2002, totaled $49,151,216.59; the unpaid principal amountof the Revolving B Advances on and as of the opening of business on April 17,2002, totaled $0; and the unpaid principal amount of the Term Loan on and as ofthe opening of business on April 17, 2002, totaled $13,725,000.00.

 

**6.             Representationsand Warranties**. Borrower represents and warrants to Agent and Lenders, to induce Agentand Lenders to enter into this Amendment, that no Default or Event of Defaultexists on the date hereof; the execution, delivery and performance of thisAmendment have been duly authorized by all requisite corporate action on thepart of Borrower and this Amendment has been duly executed and delivered byBorrower; and all of the representations and warranties made by Borrower in theCredit Agreement are true and correct on and as o f the date hereof.

 

**7.             Breachof Amendment**. This Amendment shall be part of the Credit Agreement and a breach of anyof any representation, warranty or covenant here in shall constitute an Eventof Default.

 

**8.             Expensesof Agent and Lenders**.  Borrower agrees to pay, **ondemand**, all reasonable costs and expenses incurred by Agent andLenders in connection with the preparation, negotiation and execution of thisAmendment and any other Loan Documents executed pursuant hereto and any and allamendments, modifications, and supplements thereto, including, withoutlimitation, the costs and fees of Agent’s legal counsel and any taxes orexpenses associated with or incurred in connection with any instrument oragreement referred to herein or contemplated hereby.

 

**9.             Effectiveness;Governing Law**. This Amendment shall be effective upon acceptance by Agent andLenders  (notice of which acceptance ishereby waived), whereupon the same shall be governed by and construed inaccordance with the internal laws of the State of New York.

 

**10.          Successorsand Assigns**. This Amendment shall be binding upon and inure to the benefit of theparties hereto and their respective successors and assigns.

 

**11.          NoNovation, etc**. Except as otherwise expressly provided in this Amendment, nothing hereinshall be deemed to amend or modify any provision of the Credit Agreement or anyof the other Loan Documents, each of which shall remain in full force andeffect.  This Amendment is not intendedto be, nor shall it be construed to create, a novation or accord andsatisfaction, and the Credit Agreement as herein modified shall continue infull force and effect.

 

2

----

 

**12.          Counterparts;Telecopied Signatures**.  This Amendment may be executed in any number of counterparts andby different parties to this Amendment on separate counterparts, each of which,when so executed, shall be deemed an original, but all such counterparts shallconstitute one and the same agreement. Any signature delivered by a party by facsimile transmission shall bedeemed to be an original signature hereto.

 

**13.          FurtherAssurances**. Borrower agrees to take such further actions as Agent and Lenders shallreasonably request from time to time in connection herewith to evidence or giveeffect to the amendments set forth herein or any of the transactionscontemplated hereby.

 

**14.          SectionTitles**. Section titles and references used in this Amendment shall be withoutsubstantive meaning or content of any kind whatsoever and are not a part of theagreements among the parties hereto.

 

**15.          Releaseof Claims.  To induce Agent andLenders to enter into this Amendment, Borrower hereby releases, acquits andforever discharges Agent and each Lender, and all their respective officers, directors,agents, employees, successors and assigns of Lender, from any and allliabilities, claims, demands, actions or causes of action of any kind or nature(if there be any), whether absolute or contingent, disputed or undisputed, atlaw or in equity, or known or unknown, that Borrower now has or ever hadagainst Agent and each Lender arising under or in connection with any of theLoan Documents or otherwise.  Borrowerrepresents and warrants to Agent and Lenders that Borrower has not transferredor assigned to any Person any claim that Borrower ever had or claimed to haveagainst Agent or any Lender.**

 

[Amendment continues on the following page]

 

3

----

 

**16.          Waiverof Jury Trial.  To the fullestextent permitted by Applicable Law, the parties hereto each hereby waives theright to trial by jury in any action, suit, counterclaim or proceeding arisingout of or related to this Amendment.**

 

IN WITNESSWHEREOF, the parties hereto have caused this Amendment to be duly executedunder seal, and delivered by their respective duly authorized officers on thedate first written above.

 
| ATTEST:          | **AAF-MCQUAY INC.**                                           |
|------------------|---------------------------------------------------------------|
|             | (“Borrower”)                                        |
|             |                                                          |
|             |                                                          |
|             |                                                          | By: |   |   |
|             | Name:                                                         |   |   |   | Name: |   |   |
|             | Title:                                                        |   |   |   | Title: |   |   |
|             |                                                          |   |
| [CORPORATE SEAL] |                                                          |   |   |
|             |                                                          |   |
|             | **PNC BANK, NATIONAL ASSOCIATION**, as a Lender  and as Agent |
|             |                                                          |   |
|             |                                                          |   |
|             | By:                                                           |   |   |
|             |                                                          | Name: |   |   |
|             |                                                          | Title: |   |   |
|             |                                                          |   |
|             |                                                          |   |
|             | **BANK OF AMERICA, N.A**., as a Lender                        |
|             |                                                          |   |
|             |                                                          |   |
|             | By:                                                           |   |   |
|             |                                                          | Name: |   |   |
|             |                                                          | Title: |   |   |
|             |                                                          |   |
|             |                                                          |   |
|             | **US BANK N.A.** (f/k/a Firstar Bank, N.A.), as  a Lender     |
|             |                                                          |   |
|             |                                                          |   |
|             | By:                                                           |   |   |
|             |                                                          | Name: |   |   |
|             |                                                          | Title: |   |   |
|             |                                                          |   |
|                  |                                                               |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

 

4

----

 
|   | **FLEET CAPITAL CORPORATION,** as a Lender |
|--------|--------------------------------------------|
|   |                                       |   |
|   |                                       |   |
|   | By:                                        |   |   |
|   |                                       | Name: |   |   |
|   |                                       | Title: |   |   |
|   |                                       |   |
|   |                                       |   |
|   | **BANK ONE, MICHIGAN,** as a Lender        |
|   |                                       |   |
|   |                                       |   |
|   | By:                                        |   |   |
|   |                                       | Name: |   |   |
|   |                                       | Title: |   |   |
|        |                                            |  |  |  |  |  |  |  |

 

5

----