SECTION HVAC AIR-DISTRIBUTION SYSTEM CLEANING

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1 SECTION HVAC AIR-DISTRIBUTION PART 1 - GENERAL 1.1 SUMMARY A. Section includes cleaning of interior surfaces of HVAC equipment. The HVAC equipment cleaning work includes the following: 1. Air handling units including, but not limited to, preheat, reheat, and cooling coils, bypass dampers, fans, plenums, and zone dampers. B. The HVAC equipment cleaning work includes verification, through inspection and/or testing by the cleaning contractor, as specified herein and as indicated in referenced NADCA standards. C. The HVAC equipment cleaning work does not include cleaning of existing or installed ductwork. 1.2 DEFINITIONS A. ASCS: Air System Cleaning Specialist. B. NADCA: National Air Duct Cleaners Association. C. SMACNA: Sheet Metal and Air Conditioning Contractors' National Association. 1.3 SUBMITTALS A. Manufacturer Certificates: Signed by manufacturer certifying that products comply with requirements. B. Qualifications: For Cleaning Contractor and project supervisor. C. Field Test Reports: Certified copies of field quality-control test reports. 1.4 QUALITY ASSURANCE A. Contractor Qualifications: Subcontract the HVAC cleaning work to a single firm that specializes in the cleaning of HVAC equipment, with a minimum 5 years successful experience in cleaning HVAC equipment comparable to that shown for the project, in not less than 3 projects of similar scope, to the satisfaction of the Architect; that is a certified member of the National Air Duct Cleaners Association (NADCA); that employs not less than one (1) Air System Cleaning Specialist (ASCS), as certified by NADCA, on a full time basis; that will provide an Air System Cleaning Specialist as a project supervisor on a full time basis; that has organized quality control and testing procedures, to properly verify the results of the cleaning work; and that can provide the necessary equipment, materials, and labor to adequately perform the cleaning work without causing any delay in the project. CHICAGO HIGH SCHOOL FOR THE ARTS HVAC AIR-DISTRIBUTION

2 PART 2 - PRODUCTS 2.1 MATERIALS A. Biocidal Agents: Registered with the U.S. Environmental Protection Agency (EPA) for use within HVAC systems. PART 3 - EXECUTION 3.1 EXAMINATION A. Examine existing systems, adjacent construction, and conditions under which work is to be performed to determine appropriate methods, tools, and equipment required for performance of work. 1. Damaged components with the HVAC systems and conditions detrimental to the performance of the work discovered during the examination shall be documented in a written report and submitted to the Board Authorized Representative. B. Record and mark settings of controls, dampers, and other directional devices within the HVAC system, to ensure those components can be returned to those settings at the completion of the HVAC cleaning work. C. Perform Project Evaluation and Recommendation according to NADCA ACR D. Proceed with work only after unsatisfactory conditions have been corrected and after all HVAC equipment renovation has been completed, but prior to the final balancing of the HVAC systems. 3.2 HVAC EQUIPMENT CLEANING A. General: 1. Containment: Debris removed during cleaning shall be collected and precautions must be taken to ensure that debris is not dispersed outside the HVAC system during the cleaning process. 2. Particulate Collection: Where the particulate collection equipment is exhausting inside the building. HEPA filtration with 99.97% collection efficiency for 0.3 micron size (or greater) particles shall be used. Mechanical cleaning operations shall be undertaken only with particulate collection equipment in place including adequate filtration to contain debris removed from the HVAC system. When the particulate collection equipment is exhausting outside the building, precautions shall be taken to locate the equipment down wind and away from all air intakes and other points of entry into the building. 3. Controlling odors: Control offensive odors and/or mist vapors during the cleaning process. Refer to Division 01 Section, "Dust, Fume and Odor Control." 4. Cleaning: Visibly clean all system components as defined in applicable NADCA standards. Upon completion, all components must be returned to those settings recorded prior to cleaning operations. 5. Removal: Remove visible surface contaminants and deposits from within the HVAC system in strict accordance with these specifications and NADCA recommendations. CHICAGO HIGH SCHOOL FOR THE ARTS HVAC AIR-DISTRIBUTION

3 6. Verification: Verification of HVAC system cleanliness shall be determined after mechanical cleaning, but before the application of any treatment or introduction of any treatment-related substance, including biocidal agents and coatings. B. Air-Volume Control Devices: Existing dampers and any-directional mechanical devices inside the HVAC system to remain must have their position marked prior to cleaning and upon completion must be restored to their marked position. C. Service Openings: Utilize service openings, at various points of the HVAC system for physical and mechanical entry and inspection. 1. Utilize the existing openings already installed in the HVAC system where possible. 2. Other access points shall be provided, where required, and shall be sealed in accordance with industry codes and standards. Refer to Division 23 Sections "Metal Ducts" and "Ductwork Accessories." 3. Closures must not significantly hinder, restrict, or alter the air-flow within the system. 4. Closures must be properly insulated to prevent heat loss/gain or condensation on surfaces within insulated systems. 5. Openings must not compromise the structural integrity of the system. 6. Construction techniques used in the creation of openings shall conform to requirements of the authority having jurisdiction and applicable NFPA, SMACNA and NADCA standards. 7. Cutting service openings into flexible duct is not permitted. 8. All service openings capable of being re-opened for future inspection or remediation shall be clearly marked and shall have their location recorded in project record documents. D. Air Distribution Devices (registers, grilles & diffusers): Clean all existing air distribution devices to remain. E. Air Handling Units, Terminal Units (VAV, FPB, dual duct boxes, etc.) Blowers and Exhaust Fans: Clean supply, return and exhaust fans, including blowers, fan housings, air chambers and plenums, heaters/cooling coils, scrolls, blades, vanes, shafts, baffles, dampers and drive assemblies. All visible surface contamination shall be removed. 1. Clean all AHU internal surfaces, components, condensate collectors and drains. 2. Assure that a suitable operative drainage system is in place prior to beginning wash down procedures. 3. Clean all coils and related components, including evaporator fins. 4. Clean all mixing box internal surfaces, components, condensate collectors and drains. F. Debris disposal: All debris removed from the HVAC System shall become property of the Contractor and shall be removed from the Site and disposed of legally. G. Source Removal Cleaning Methods: The HVAC system shall be cleaned using Source Removal mechanical cleaning methods noted in NADCA ACR The cleaning method(s) selected shall render the HVAC system visibly clean and capable of passing cleaning verification methods and other specified tests. No cleaning method, or combination of methods, should be used which could potentially damage components, or alter the integrity, of the HVAC system. CHICAGO HIGH SCHOOL FOR THE ARTS HVAC AIR-DISTRIBUTION

4 1. All methods shall incorporate the use of vacuum collection devices that are operated continuously during cleaning. A vacuum device shall be connected to the downstream end of the section being cleaned through a predetermined opening. The vacuum collection device must be of sufficient power to render all areas being cleaned under negative pressure. 2. All vacuum devices, including hand-held and wet vacuums, exhausting air inside the building shall be equipped with HEPA filters (99.97 % efficiency). 3. All vacuum devices exhausting air outside the facility shall be equipped with particulate collection including adequate filtration to contain debris removed from the HVAC system. Such devices shall exhaust in a manner that will not allow contaminants to reenter the facility. Release of debris outdoors shall be done in accordance with requirements of authority having jurisdiction. H. Biocidal Agents and Coatings: 1. Biocidal agents shall only be applied if active fungal growth is found, or where unacceptable levels of fungal contamination have been verified through the testing. 2. Application of any biocidal agents used to control the growth of fungal or bacteriological contaminants shall be performed after the removal of surface deposits and debris. 3. Only biocidal agents registered by the U. S. Environmental Protection Agency (EPA) specifically for use within HVAC system shall be used. 4. Biocidal agents shall be applied in strict accordance with manufacturer's instructions. 5. Biocidal coating products for both porous and non-porous surfaces shall be EPA registered, water soluble solutions. I. Cleaning Mineral-Fiber Insulation Components: 1. Fibrous-glass or acoustical insulation elements present in equipment shall be thoroughly cleaned with HEPA vacuuming equipment, with the HVAC system under constant negative pressure. Care shall be taken to ensure that insulation remains dry during cleaning. 2. Cleaning methods used shall not cause damage to fibrous-glass components and will render the system capable of passing the HVAC System Cleanliness Tests noted and outlined in NADCA ACR J. Visual Inspection: The HVAC equipment and systems shall be visually inspected to ensure that no visible contaminants remain following cleaning. Visual inspection shall take place after mechanical cleaning and before the HVAC systems are returned to normal operation. 1. Where contaminants are found, those portions of the HVAC systems shall be re-cleaned and reinspected visually, with this process repeated until all areas of the HVAC systems are found to be free of contaminants. 2. The Owner may engage an independent agent to verify cleanliness through gravimetric or rope testing analysis testing, in accordance with NADCA standards and recommendations. a. Any items found shall be documented in a written report, which is to be submitted to the Board Authorized Representative, and those areas of the HVAC systems are to be re-cleaned by the Contractor at no additional cost to the Owner. CHICAGO HIGH SCHOOL FOR THE ARTS HVAC AIR-DISTRIBUTION

5 K. Adjustment: At the conclusion of the HVAC cleaning work, but before the HVAC systems are returned to normal operation, the Contractor is to return all controls, dampers, and other directional devices within the HVAC system to the settings recorded prior to the start of cleaning. L. Reporting: Where areas of the HVAC systems have been found to be damaged and/or in need of repair, the Contractor shall prepare a written report indicating the nature and locations of these items. A copy of this report shall be submitted to the Board Authorized Representative. END OF SECTION CHICAGO HIGH SCHOOL FOR THE ARTS HVAC AIR-DISTRIBUTION