ANSI/RESNET/ACCA 310-2020 Standard for Grading the Installation of HVAC Systems PDF

ANSI/RESNET/ACCA 310-2020 Standard for Grading the Installation of HVAC Systems June 23, 2020 Residential Energy Services Network, Inc. P.O. Box 4561 Oceanside, CA 92052-4561 http://resnet.us/ Air Conditioning Contractors of America 2800 Shirlington Road, Suite 300 Arlington, VA 22203 www.acca.org ©Residential Energy Services Network, 2018. All rights reserved. RESNET Standards Development Committee 300 Gayathri Vijayakumar, Chair* Thiel Butner* Terry Clausing* Charlie Haack* Philip Fairey* Dean Gamble* C.R. Herro* Kelly Parker* Jerry Phelan* Dave Roberts* Amy Schmidt* Brian Shanks* Jason Toves* Ian Finlayson* Josh Spence* * Denotes members of voting status when the document was approved for publication RESNET Standards Management Board Philip Fairey, Chair Wes Davis David B. Goldstein CR Herro David E. Walls Richard W. Dixon, Manager of Standards The 2020 edition of this Standard was first approved for publication on June, 16, 2020, by the RESNET Standards Management Board. SPECIAL NOTE This ANSI/RESNET/ICC Standard is a voluntary consensus standard developed under the auspices of the Residential Energy Services Network (RESNET) in accordance with RESNET’s Standards Development Policy and Procedures Manual, Version 2.1, August 25, 2017. RESNET is an American National Standards Institute (ANSI) Accredited Standards Developer. Consensus is defined by ANSI as “substantial agreement reached by directly and materially affected interest categories.” This signifies the concurrence of more than a simple majority but not necessarily unanimity. Consensus requires that all views and objections be considered, and that an effort be made toward their resolution. Compliance with this standard is voluntary until and unless a legal jurisdiction makes compliance mandatory. RESNET obtains consensus through participation of it national members, associated societies, and public review. This Standard is under continuous maintenance in accordance with Section 10.9 of the RESNET Standard Development Policy and Procedures Manual. Continuous maintenance proposals should be submitted to the Manager of Standards via the online form on the RESNET website. The Manual and online form can be accessed from the RESNET website at https://www.resnet.us/about/standards/resnet-ansi/. The Manager of Standards should be contacted for: a. Interpretation of the contents of this Standard b. Participation in the next review of the Standard c. Offering constructive criticism for improving the Standard d. Permission to reprint portions of the Standard Table of Contents Foreword (Informative) ................................................................................................................1 1. Purpose ................................................................................................................................1 2. Scope ....................................................................................................................................1 3. Definitions............................................................................................................................2 4. Task 1: Evaluation of the Design .........................................................................................7 4.1 Overview ..................................................................................................................7 4.2 Required Design Information ..................................................................................7 4.3 Evaluation of Design Information ........................................................................12 5. Task 2: Evaluation of the Total Duct Leakage ..................................................................15 5.1 Overview ................................................................................................................15 5.2 Prerequisites ...........................................................................................................16 5.3 Procedure to Measure Total Duct Leakage ............................................................16 5.4 Designating the Total Duct Leakage Grade ...........................................................16 6. Task 3: Evaluation of the Blower Fan Volumetric Airflow ..............................................17 6.1 Overview ................................................................................................................17 6.2 Prerequisites ...........................................................................................................18 6.3 Determination of Applicable Test Method ............................................................19 6.4 Procedure to Prepare the Dwelling and Forced Air HVAC System ......................19 6.4.1 Position Dampers .......................................................................................20 6.4.2 Position Registers.......................................................................................20 6.4.3 Ventilation Openings .................................................................................20 6.4.4 Settings for Fans Other than the HVAC System Blower Fan....................20 6.4.5 Settings for HVAC System ........................................................................20 6.5 Pressure Matching Method ....................................................................................21 6.5.1 Equipment Needed .....................................................................................21 6.5.2 Procedure to Conduct Pressure Matching Airflow Test ...........................21 6.6 Flow Grid ...............................................................................................................23 6.6.1 Equipment Needed .....................................................................................23 6.6.2 Procedure to Conduct Flow Grid Airflow Test..........................................23 6.7 Flow Hood .............................................................................................................25 6.7.1 Equipment Needed .....................................................................................25 6.7.2 Procedure to Conduct Flow Hood Airflow Test ........................................25 6.8 OEM Static Pressure Table Method ......................................................................26 6.8.1 Equipment Needed ....................................................................................26 6.8.2 Documentation Needed .............................................................................26 6.8.3 Procedure to Conduct OEM Static Pressure Airflow Test ........................26 6.9 Designating the Blower Fan Volumetric Airflow Grade ......................................29 7. Task 4: Evaluation of the Blower Fan Watt Draw.............................................................29 7.1 Overview ................................................................................................................29 7.2 Prerequisites ...........................................................................................................30 7.3 Procedure to Prepare the Dwelling and Forced-Air HVAC System......................30 7.3.1 Independent Verification Report................................................................30 7.3.2 Settings for HVAC System ........................................................................30 7.4 Portable Plug-In Watt Meter ..................................................................................31 7.4.1 Equipment Needed .....................................................................................31 7.4.2 Procedure to Measure Blower Fan Watt Draw ..........................................31 7.5 Clamp-On Watt Meter .................................................................................................32 7.5.1 Equipment Needed .....................................................................................32 7.5.2 Procedure to Measure Blower Fan Watt Draw ..........................................32 7.6 Analog Utility Revenue Meter ...............................................................................33 7.6.1 Equipment Needed .....................................................................................33 7.6.2 Procedure to Measure Blower Fan Watt Draw .........................................34 7.7 Digital Utility Revenue Meter ...............................................................................34 7.7.1 Equipment Needed .....................................................................................34 7.7.2 Procedure to Measure Blower Fan Watt Draw ..........................................34 7.8 Designating the Blower Fan Watt Draw Grade .....................................................35 8. Task 5: Evaluation of the Refrigerant Charge ...................................................................35 8.1 Overview ................................................................................................................35 8.2 Prerequisites ...........................................................................................................36 8.3 Determination of Applicable Test Methods ...........................................................36 8.3.1 Equipment Needed .....................................................................................36 8.3.2 Procedures to Determine Applicable Test Methods ..................................36 8.4 Non-Invasive Method ............................................................................................37 8.4.1 Procedure to Prepare the Dwelling and Forced-Air HVAC System .........37 8.4.2 Equipment Needed .....................................................................................38 8.4.3 Procedure to Evaluate the Refrigerant Charge...........................................38 8.5 Weigh-In Method ...................................................................................................44 8.5.1 Equipment Method....................................................................................44 8.5.2 Documentation Needed ..............................................................................44 8.5.3 Procedure to Evaluate the Refrigerant Charge...........................................45 8.6 Designating the Refrigerant Charge Grade ............................................................46 9. References ..........................................................................................................................47 Appendix A....................................................................................................................................49 Appendix B...................................................................................................................................167 Appendix C...................................................................................................................................169 ANSI/RESNET/ACCA 310-2020 Standard for Grading the Installation of HVAC Systems Foreword (Informative) This Standard provides a methodology for evaluating the installation quality of Unitary HVAC systems. It’s comprised of five tasks - a design review, a total duct leakage test, a Blower Fan volumetric airflow test, a Blower Fan watt draw test, and a non-invasive evaluation of refrigerant charge. The five tasks are designed to be completed in sequence. With the completion of each task, the results are evaluated for compliance with specified thresholds. For Task 1, these thresholds are design tolerances. For Tasks 2 through 5, the thresholds are installation quality grades. Furthermore, for Tasks 1 through 3, specified thresholds must be satisfied or the subsequent tasks cannot be completed. A visual representation of the workflow and the diagnostic test methods is shown in Figure 1. Figure 1: Illustration of Workflow and Diagnostic Test Methods In this standard, the terms Townhouse, Dwelling Unit, and Sleeping Unit are interchangeable with the term Dwelling, except where specifically noted. This Standard contains both normative requirements and informative supporting material. The normative requirements must be complied with to conform to the Standard. Informative materials only provide supportive content and are marked as such. 1. Purpose. This standard establishes the procedures, tolerances, and record keeping practices for evaluating and grading elements of an HVAC System’s design and installation. This standard is intended to support consistency in energy rating and labeling. It is intended for use by home energy raters, energy auditors, or HVAC contractors. 2. Scope. This standard is applicable to Unitary HVAC Systems including air conditioners and heat pumps up to 65 kBtuh and furnaces up to 125 kBtuh in detached one- and two-family Dwellings, Townhouses, as well as in Dwelling Units and Sleeping Units that have their own HVAC system separate from other units. Page 1 of 169 3. Definitions. AHRI Reference Number – The unique identifier assigned by the Air-Conditioning, Heating, & Refrigeration Institute (AHRI) to a specific piece of equipment or combination of equipment that it has certified. Air Conditioner – A vapor-compression refrigeration device that transfers heat from a location being cooled to another location using the physical properties of an evaporating and condensing fluid known as a refrigerant. Architectural Option – A modification to a portion of an Architectural Plan that may be optionally used. Architectural Plan – An architectural drawing defining the room quantity, room type, and dimensions of a Dwelling. Authority Having Jurisdiction – The agency or agent responsible for enforcing this standard. Bedroom – For one- and two-family Dwellings and Townhouses, a room 1 or space 70 square feet of floor area or greater, with Egress Window or skylight, and doorway to the main body of the Dwelling Unit, that can be used for sleeping. For all other Dwelling Units, a room 2 or space that can be used for sleeping. For all Dwelling or Sleeping Units, the number of Bedrooms shall not be less than one. Blower Fan – The fan inside the equipment of a Forced-Air HVAC System that forces the heated and/or cooled air to be distributed within a Dwelling. Boiler – A space-heating appliance with a capacity up to 225 kBtuh in which liquid is heated by burning fuel or converting electrical energy. Climate Condition – The classification of a climate, as defined by ACCA Manual S, into Condition A or B. Condition B represents climates for which the sensible heat ratio is ≥ 0.95 and the ratio of Heating Degree Days to Cooling Degree Days is ≥ 2.0 3. Climates that do not meet Condition B are considered to be Condition A. Condensing Temperature – The refrigerant Saturation Temperature measured at the service valve at the condenser coil entrance. Condensing Temperature Over Ambient (CTOA) – A constant value that represents the difference between the Condensing Temperature and the outdoor air used to cool the refrigerant in the condenser coil. (Informative Note) A "den," "library," "home office" or other similar rooms with a closet, Egress Window, doorway to the main body of the Dwelling Unit, and 70 square feet of floor area or greater are considered a Bedroom, but living rooms, foyers, and other rooms not intended for sleeping, are not. The number of rooms identified as Bedrooms is used to determine the number of occupants. 2 (Informative Note) Informative Annex A of Standard ANSI/RESNET/ICC 380 contains a table that summarizes parts of a Dwelling Unit that are included in Conditioned Floor Area. 3 (Informative Note) ACCA uses a base temperature of 65 °F (18 °C) for heating and 50 °F (10 °C) for cooling. 1 Page 2 of 169 Conditioned Floor Area (CFA) 4 – The floor area of the Conditioned Space Volume within a building or Dwelling Unit, not including the floor area of attics, crawlspaces, and basements below air sealed and insulated floors. The following specific spaces are addressed to ensure consistent application of this definition: • The floor area of a wall assembly that is adjacent to Conditioned Space Volume shall be included. • The floor area of a basement shall be included if the party conducting the evaluation has either: o Obtained an ACCA Manual J, S, and either B or D report and verified that both the heating and cooling equipment and distribution system are designed to offset the entire design load of the volume, or, o Verified through visual inspection that both the heating and cooling equipment and distribution system serve the volume and, in the judgement of the party conducting evaluations, are capable of maintaining the heating and cooling temperatures specified by the Thermostat section in Table 4.2.2(1) in ANSI/RESNET/ICC 301. • The floor area of a garage shall be excluded, even when it is conditioned. • The floor area of a thermally isolated sunroom shall be excluded. • The floor area of an attic shall be excluded, even when it is Conditioned Space Volume. • The floor area of a crawlspace shall be excluded, even when it is Conditioned Space Volume. Conditioned Space Volume 4 – The volume within a Dwelling Unit serviced by a space heating or cooling system designed to maintain space conditions at 78 °F (26 °C) for cooling and 68 °F (20 °C) for heating. The following specific spaces are addressed to ensure consistent application of this definition: • • • If the volume both above and below a floor assembly meets this definition and is part of the Rated Dwelling Unit, then the volume of the floor assembly shall also be included. Otherwise the volume of the floor assembly shall be excluded. o Exception: The wall height shall extend from the finished floor to the bottom side of the floor decking above the Rated Dwelling Unit for non-top floor level Dwelling Units and to the exterior enclosure air barrier for top floor level Dwelling Units. If the volume of at least one of the spaces horizontally adjacent to a wall assembly meets this definition, and that volume is part of the Rated Dwelling Unit, then the volume of the wall assembly shall also be included. Otherwise, the volume of the wall assembly shall be excluded. o Exception: If the volume of one of the spaces horizontally adjacent to a wall assembly is a Dwelling Unit other than the Rated Dwelling Unit, then the volume of that wall assembly shall be evenly divided between both adjacent Dwelling Units. The volume of an attic that is not both air sealed and insulated at the roof deck shall be excluded. (Informative Note) Informative Annex A of Standard ANSI/RESNET/ICC 380 contains a table that summarizes parts of a Dwelling Unit that are included in Conditioned Floor Area. 4 Page 3 of 169 • • • • • The volume of a vented crawlspace shall be excluded. The volume of a garage shall be excluded, even when it is conditioned. The volume of a thermally isolated sunroom shall be excluded. The volume of an attic that is both air sealed and insulated at the roof deck, the volume of an unvented crawlspace, and the volume of a basement shall only be included if the volume is contiguous with the Rated Dwelling Unit and the party conducting evaluations has either: o Obtained an ACCA Manual J, S, and either B or D report and verified that both the heating and cooling equipment and distribution system are designed to offset the entire design load of the volume, or, o Verified through visual inspection that both the heating and cooling equipment and distribution system serve the volume and, in the judgement of the party conducting evaluations, are capable of maintaining the heating and cooling temperatures specified by the Thermostat section in Table 4.2.2(1). The volume of a mechanical closet, regardless of access location, that is contiguous with the Rated Dwelling Unit shall be included if: o it is serviced by a space heating or cooling system designed to maintain space conditions at 78 °F (26 °C) for cooling and 68 °F (20 °C) for heating, and o it only includes equipment serving the Rated Dwelling Unit, and o the mechanical room is not intentionally air sealed from the Rated Dwelling Unit. Design Temperature Difference (DTD) – A constant value that represents the difference between the evaporator coil refrigerant’s Saturation Temperature and the return air dry-bulb temperature within normal operating load conditions. Direct-Vent Appliance – Appliances that are constructed and installed so that all air for combustion is derived from the outdoor atmosphere and all flue gases are discharged to the outdoor atmosphere. Dwelling – Any building that contains one or two Dwelling Units used, intended, or designed to be built, used, rented, leased, let or hired out to be occupied, or that are occupied for living purposes. Dwelling Unit – A single unit providing complete independent living facilities for one or more persons, including permanent provisions for living, sleeping, eating, cooking, and sanitation. Dwelling-Unit Mechanical Ventilation System – A Ventilation system consisting of powered Ventilation equipment such as motor-driven fans and blowers and related mechanical components such as ducts, inlets, dampers, filters and associated control devices that provides Dwelling-Unit Ventilation at a known or measured airflow rate. Egress Window – An operable window that provides for a means of escape and access for rescue in the event of an emergency and with the following attributes: • • • • Has a sill height of not more than 44 inches above the floor; and, Has a minimum net clear opening of 5.7 sq. ft.; and, Has a minimum net clear opening height of 24 in.; and, Has a minimum net clear opening width of 20 in.; and, Page 4 of 169 • Is operational from the inside of the room without the use of keys, tools or special knowledge. Forced-Air HVAC System – A type of HVAC System that incorporates a Blower Fan to move conditioned air. Front Orientation – The direction that the front door of a Dwelling is facing. Furnace – A space-heating appliance in which air is heated by burning fuel or converting electrical energy. Heat Pump – A vapor-compression refrigeration device that includes a reversing valve and optimized heat exchangers so that the direction of heat flow is reversed in order to transfer heat from one location to another using the physical properties of an evaporating and condensing fluid known as a refrigerant. HVAC System – Cooling-only, heating-only, or combined cooling-heating equipment, including any supply and/or return distribution systems. Independent Verification Report – A report provided by a party operating under a third-party quality control program. Mechanical Draft System – A venting system designed to remove flue or vent gases by mechanical means, that consists of an induced-draft portion under nonpositive static pressure or a forced-draft portion under positive static pressure. Mini-Split Air Conditioner (MNAC) – An Air Conditioner that has variable refrigerant flow and distributed refrigerant technology with a single outdoor unit serving a single indoor unit. The outdoor unit contains a single compressor or multiple compressors or a variable capacity compressor. The indoor unit has a coil, an air movement device 5 intended for single zone air distribution, and a temperature sensing control. The units are matched with a zone temperature control device. Mini-Split Heat Pump (MNHP) – A Heat Pump that has variable refrigerant flow and distributed refrigerant technology with a single outdoor unit serving a single indoor unit. The outdoor unit contains a single compressor or multiple compressors or a variable capacity compressor. The indoor unit has a coil, an air movement device 5 intended for single zone air distribution, and a temperature sensing control. The units are matched with a zone temperature control device. Multi-Split Air Conditioner (MTAC) – An Air Conditioner that has variable refrigerant flow and distributed refrigerant technology with the capability of serving multiple indoor units with a single outdoor unit. The outdoor unit contains a single compressor or multiple compressors or a variable capacity compressor. Each indoor unit has a coil, an air movement device 5 intended for single zone air distribution, and a temperature sensing control. The units are matched with a zone temperature control device. 5 (Informative Note) The air movement device is typically ductless or supports duct systems ≤ 10 feet in length. Page 5 of 169 Multi-Split Heat Pump (MTHP) – A Heat Pump that has variable refrigerant flow and distributed refrigerant technology with the capability of serving multiple indoor units with a single outdoor unit. The outdoor unit contains a single compressor or multiple compressors or a variable capacity compressor. Each indoor unit has a coil, an air movement device 5 intended for single zone air distribution, and a temperature sensing control. The units are matched with a zone temperature control device. Natural Draft System – A venting system designed to remove flue or vent gases under nonpositive static vent pressure entirely by natural draft. OEM Static Pressure Table – Documentation produced by a Forced-Air HVAC System equipment manufacturer that indicates the Blower Fan airflow at specified fan-speed settings, static pressure values, and in some instances voltage. Other Equipment Type – Any HVAC equipment type that is not an Air Conditioner, Boiler, Furnace, or Heat Pump. Other Motor Type – Any Blower Fan motor type that is not a Permanent Split Capacitor (PSC) or Electronically Commutated Motor (ECM). Other Ventilation Standard – Any ventilation standard that is not ASHRAE 62.2-2010, ASHRAE 62.2-20103, or ASHRAE 62.2-2016. Saturation Temperature – The temperature at which the refrigerant undergoes a phase change in either the condenser or evaporator coils. Sleeping Unit – A room or space in which people sleep, which can also include permanent provisions for living, eating, and either sanitation or kitchen facilities but not both. Such rooms and spaces that are also part of a Dwelling Unit are not Sleeping Units. Target Liquid Line Temperature – The calculated target temperature of the liquid line. Target Subcooling – The manufacturer prescribed subcooling for the equipment being tested. Target Suction Line Temperature – The calculated target temperature of the suction line. Target Superheat – The manufacturer prescribed superheat for the equipment being tested. Townhouse – A single-family Dwelling Unit constructed in a group of three or more attached units in which each unit extends from the foundation to roof and with open space on at least two sides. Unconditioned Space Volume 6 – The volume within a building or Dwelling Unit that is not Conditioned Space Volume but which contains heat sources or sinks that influence the temperature of the area or room. The following specific spaces are addressed to ensure consistent application of this definition: (Informative Note) Informative Annex A of Standard ANSI/RESNET/ICC 380 contains a table that summarizes parts of a Dwelling Unit that are included in Unconditioned Space Volume. 6 Page 6 of 169 If either one or both of the volumes above and below a floor assembly is Unconditioned Space Volume, then the volume of the floor assembly shall be included. If the volume of both of the spaces horizontally adjacent to a wall assembly are Unconditioned Space Volume, then the volume of the wall assembly shall be included. The volume of an attic that is not both air sealed and insulated at the roof deck shall be included. The volume of a vented crawlspace shall be included. The volume of a garage shall be included, even when it is conditioned. The volume of a thermally isolated sunroom shall be included. The volume of an attic that is both air sealed and insulated at the roof deck, the volume of an unvented crawlspace, and the volume of a basement shall be included unless it meets the definition of Conditioned Space Volume. • • • • • • • Unitary – One or more factory-made assemblies which normally may include an evaporator or cooling coil, a compressor and condenser combination, and may include a heating function. The equipment can be ducted or ductless; it can be a split-system or single package. Ventilation – The process of providing outdoor air directly to a Dwelling by natural or mechanical means. Such air may or may not be conditioned. 4. Task 1: Evaluation of the Design. 4.1. Overview. This procedure shall be completed by first collecting the design information specified in Section 4.2, then verifying that all required information has been provided and falls within the tolerances specified in Section 4.3. As an alternative to completing the procedures defined in Section 4.2 and 4.3, if an Independent Verification Report is obtained containing the design information specified in Section 4.2 and confirmation that all required information has been provided and falls within the tolerances specified in Section 4.3, and the report is approved for use by an entity adopting and requiring the use of this Standard, then the reported values shall be permitted to be used. 4.2. Required Design Information. The following design information shall be collected by the person completing the evaluation for the Dwelling. 4.2.1. Architectural design documentation, consisting of the following: 4.2.1.1. The Architectural Plan. 4.2.1.2. Any Architectural Options for the Plan. 4.2.2. HVAC design basis, consisting of the following: 4.2.2.1. The designer name. 4.2.2.2. The designer company. 4.2.2.3. The date of design. Page 7 of 169 4.2.2.4. The architectural scope of the HVAC design, consisting of the following: 4.2.2.4.1. If a Dwelling or Townhouse, or a Dwelling Unit or Sleeping Unit within: 4.2.2.4.1.1. The name of the Architectural Plan that the HVAC design is based on or the unique address of the building. 4.2.2.4.1.2. Any Architectural Option(s) used in the HVAC design, and a list of other Architectural Option(s), if any, that the design can be used with. 4.2.2.4.2. If a Dwelling Unit or Sleeping Unit not within a Dwelling or Townhouse: 4.2.2.4.2.1. A unique identifier for the building that the unit is within 7. 4.2.2.4.2.2. The name of the Architectural Plan that the HVAC design is based on, and a list of other Architectural Plan(s), if any, that the design can be used with. 4.2.2.4.2.3. Any Architectural Option(s) used in the HVAC design, and a list of other Architectural Option(s), if any, that the design can be used with. 4.2.2.5. If a software program was used to complete the design, the software program name and version that was used. 4.2.3. Dwelling-Unit Mechanical Ventilation System design for each system that serves the Dwelling, consisting of the following: 4.2.3.1. A unique name or identifier for the system 8. 4.2.3.2. The specified system type: supply, exhaust, balanced without recovery, ERV, HRV, ventilation dehumidifier, or other. 4.2.3.3. The specified control location for the system 9. 4.2.3.4. For systems serving Dwelling Units or Sleeping Units not within a Dwelling or Townhouse: 4.2.3.4.1. The specified system manufacturer and model number. 4.2.3.4.2. The unit(s) served by the system. 4.2.3.5. The name of the Ventilation zone(s) 10 served by the system. 4.2.3.6. An overview of each Ventilation zone that the system serves, consisting of the following information. 4.2.3.6.1. The design basis for the Ventilation airflow rate and run-time for the Ventilation zone: ASHRAE 62.2-2010, ASHRAE 62.2-2013, or ASHRAE 62.22016, or Other Ventilation Standard. 4.2.3.6.2. The number of Bedrooms within the Ventilation zone. 4.2.3.6.3. The floor area of the Ventilation zone. (Informative Note) For example, the name of the development or the building’s address. (Informative Note) For example, “Bath Fan 1”, “ERV 1”. 9 (Informative Note) Examples of common locations include bathroom or utility room. 10 (Informative Note) Examples of Ventilation zones include Whole Dwelling, Upper Level, Lower Level, Basement. 7 8 Page 8 of 169 4.2.3.6.4. The design’s Ventilation airflow rate, runtime per cycle, and cycle time for the Ventilation zone. 4.2.3.6.5. The design’s time-averaged Ventilation airflow rate for the Ventilation zone, calculated using Equation 1. 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇_𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴 𝑉𝑉𝑉𝑉𝑉𝑉𝑉𝑉 𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅 = 𝑉𝑉𝑉𝑉𝑉𝑉𝑉𝑉 𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅 × Where: 𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅 𝑃𝑃𝑃𝑃𝑃𝑃 𝐶𝐶𝐶𝐶𝐶𝐶𝐶𝐶𝐶𝐶 𝐶𝐶𝐶𝐶𝐶𝐶𝐶𝐶𝐶𝐶 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇 (1) Time_Averaged Vent Rate = The average Ventilation airflow rate. Vent Rate = The design’s Ventilation airflow rate reported in Section 4.2.3.6.4. Runtime Per Cycle = The runtime per cycle reported in Section 4.2.3.6.4. Cycle Time = The cycle time reported in Section 4.2.3.6.4. 4.2.4. Heat gain and heat loss loads for each heated or cooled zone in the Dwelling, consisting of the following: 4.2.4.1. The name of the heated or cooled zone 11. 4.2.4.2. For Dwelling Units and Sleeping Units not within a Dwelling or Townhouse, the unit’s location: 4.2.4.2.1. The top floor, mid-level floor, or bottom floor of the building, and, 4.2.4.2.2. Either a corner unit or middle unit that is between two other units. 4.2.4.3. The design basis for the heat gain and heat loss loads: ACCA Manual J v8, 2013; ACCA Manual J v8, 2016; 2017 ASHRAE Fundamentals; or per the Authority Having Jurisdiction. 4.2.4.4. Confirmation that the loads were calculated room-by-room. Exception: For Dwelling Units and Sleeping Units not within a Dwelling or Townhouse, the loads shall be permitted to be calculated as a single block. 4.2.4.5. The indoor heating design temperature and indoor cooling design temperature used. 4.2.4.6. The outdoor heating design temperature, outdoor cooling design temperature, and the location and source of the outdoor conditions used 12. 4.2.4.7. The number of occupants. 4.2.4.8. The total occupant internal gains. 4.2.4.9. The total non-occupant internal gains. 4.2.4.10. The Conditioned Floor Area. 4.2.4.11. The window area. (Informative Note) Examples of heated or cooled zones include Upper Level, Master Suite, Basement. (Normative Note) The location shall include the city or weather station and the state. The source shall be ACCA Manual J, ASHRAE Handbook of Fundamentals, or the Authority Having Jurisdiction. 11 12 Page 9 of 169 4.2.4.12. The solar heat gain coefficient value used in the greatest amount of window area. 4.2.4.13. The nominal R-value of the insulation 13 used in the greatest amount of abovegrade wall area. 4.2.4.14. The nominal R-value of the insulation used in the greatest amount of ceiling area. 4.2.4.15. The infiltration rate. 4.2.4.16. The time-averaged mechanical Ventilation airflow rate. 4.2.4.17. The calculated sensible, latent, and total heat gain at design conditions for one or more orientations. 4.2.4.18. If the heat gain has been provided for more than one orientation in Section 4.2.4.17, then the difference between the maximum and minimum total heat gain across the orientations specified. 4.2.4.19. The calculated total heat loss at design conditions. 4.2.5. Specifications for all HVAC Systems serving the Dwelling, consisting of the following for each HVAC System: 4.2.5.1. A unique name or identifier for the HVAC system. 4.2.5.2. The name of the heated or cooled zone(s) 14 that the HVAC system serves. 4.2.5.3. An equipment overview, consisting of the following for each piece of equipment: 4.2.5.3.1. The equipment type: Air Conditioner, Boiler, Furnace, Heat Pump, or Other Equipment Type. 4.2.5.3.2. The equipment manufacturer(s) and model number(s) 15. 4.2.5.3.3. The AHRI Reference Number of the equipment. Exception: If an AHRI Reference Number is not available, OEM-provided documentation shall be collected with the rated efficiency of the equipment. If the equipment contains multiple components, the rated efficiency shall reflect the specific combination of indoor and outdoor components, along with confirmation from the OEM that the two components are designed to be used together. 4.2.5.3.4. If the equipment type is an Air Conditioner, Furnace, or Heat Pump, then the Blower Fan motor type: Permanent Split Capacitor (PSC), Electronically Commutated Motor (ECM), or Other Motor Type. (Informative Note) If both cavity and continuous insulation are used, the nominal R-value equals the sum of nominal R-value of the cavity and continuous insulation. 14 (Informative Note) Examples of zones include Whole Dwelling, Upper Level, Lower Level, Basement. 15 (Informative Note) For equipment types that include both an evaporator/fan-coil and a condenser, include the manufacturer and model number for both components. 13 Page 10 of 169 4.2.5.3.5. If the equipment type is an Air Conditioner, Furnace, or Heat Pump, then the Blower Fan speed type: single-speed, two-speed, or variable-speed 16. 4.2.5.3.6. If the equipment type is an Air Conditioner or Heat Pump, then the compressor speed type: single-speed, two-speed, or variable-speed. 4.2.5.3.7. If the equipment type is an Air Conditioner or Heat Pump, then whether it is also a Mini-Split Air Conditioner, Mini-Split Heat Pump, Multi-Split Air Conditioner, or Multi-Split Heat Pump. 4.2.5.3.8. If the equipment type is a Heat Pump, then the ratio of its maximum rated capacity relative to its minimum rated capacity. 4.2.5.3.9. If the equipment type is an Air Conditioner or Heat Pump, then: 4.2.5.3.9.1. The metering device type: piston or capillary tube, Thermal Expansion Value (TXV), or Electronic Expansion Valve (EEV). 4.2.5.3.9.2. If the metering device type in Section 4.2.5.3.9.1 is TXV or EEV, then the OEM-specified subcooling target at the service valve. 4.2.5.3.10. If the equipment type is an Air Conditioner or Heat Pump, then the equipment’s rated cooling efficiency 17. 4.2.5.3.11. If the equipment type is a Boiler, Furnace, or Heat Pump, then the equipment’s rated heating efficiency. 4.2.5.3.12. If the equipment type is a Boiler or Furnace, then the heating capacity type: single-stage, two-stage, or modulating. 4.2.5.3.13. If the equipment type is a Boiler or Furnace, then the venting type, either Natural Draft System, Mechanical Draft System, or Direct-Vent Appliance. 4.2.5.4. The specified performance rating and metric 18 of each filter to be installed. 4.2.5.5. Duct system design elements, if a duct system will be installed, consisting of the following: 4.2.5.5.1. The design Blower Fan airflow, expressed in cubic feet per minute or cubic meters per second of air with a density of 0.075 pounds per cubic feet (1.201 kg per cubic meter) 19: (Informative Note) While equipment typically has multiple speed settings to select from during installation, this parameter is related to the number of operational speeds that the system is capable of. Single-speed indicates a system that operates at no more than one speed setting each for heating mode and cooling mode. Two-speed indicates a system that can operate at no more than two speeds each for heating mode and cooling mode. Variable-speed indicates a system that can operate at more than two speeds. 17 (Informative Note) For example, if the metric for the rated efficiency of the equipment is SEER, then its SEER rating shall be reported; if the metric is EER, then its EER rating shall be reported; if both SEER and EEER, then both rated values shall be reported. 18 (Informative Note) For example, MERV or FPR. 19 (Informative Note) Airflow at this air density is often referred to as Standard CFM (SCFM) or Standard CMS (SCMS) and represents air at 68 °F, 50% relative humidity, and at a barometric pressure of 29.92" Hg. 16 Page 11 of 169 4.2.5.5.1.1. In cooling mode if the equipment type is an Air Conditioner or Heat Pump. 4.2.5.5.1.2. In heating mode if the equipment type is a Furnace or Heat Pump. 4.2.5.5.2. The design Blower Fan speed setting 20: 4.2.5.5.2.1. In cooling mode if the equipment type is an Air Conditioner or Heat Pump. 4.2.5.5.2.2. In heating mode if the equipment type is a Furnace or Heat Pump. 4.2.5.5.3. The design external static pressure 21. 4.2.5.5.4. The individual room-by-room names and design airflows and the sum of the design airflows across all rooms. 4.3. Evaluation of Design Information. The design documentation collected in Section 4.2 shall be reviewed to verify that all required information has been provided. In addition, the Dwelling 22 shall be compared to the design documentation to verify that the following criteria have been met. 4.3.1. If a Dwelling or Townhouse, or Dwelling Unit or Sleeping Unit within, is to be rated, then the following criteria shall be met in addition to the criteria in Section 4.3.4: 4.3.1.1. The name of the Architectural Plan or unique address of the Dwelling matches that used in the HVAC design, as documented in Section 4.2.2.4.1.1. 4.3.1.2. Any Architectural Option(s) used in the Dwelling match those used in the HVAC design or are in the list of option(s) that the design can be used with, as documented in Section 4.2.2.4.1.2. 4.3.1.3. The Conditioned Floor Area of each zone in the Dwelling is between 300 square feet smaller and 100 square feet larger than the area in the HVAC design, as documented in Section 4.2.4.10. 4.3.1.4. The window area of each zone in the Dwelling is between 60 square feet smaller and 15 square feet larger than the area in the HVAC Design, as documented in Section 4.2.4.11, or for zones with > 500 square feet of window area, between 12% smaller and 3% larger. 4.3.1.5. The Front Orientation of the Dwelling matches one of the orientations included in the orientation-specific heat gains documented in Section 4.2.4.17. 4.3.1.6. The difference between the maximum and minimum total heat gain for each zone, as documented in Section 4.2.4.18, is ≤ 6 kBtuh. (Informative Note) This is the OEM setting that corresponds with the design Blower Fan airflow. Common examples include low, medium-low, medium, medium-high, and high, but also may be defined in terms of dipswitch settings or other classifications. 21 (Informative Note) This is the sum of the supply-side and return-side static pressure, corresponding to the mode with the higher design Blower Fan airflow. 22 (Normative Note) While an initial review may be completed prior to construction, ultimately the Dwelling as constructed shall be compared to the design documentation to verify that the criteria have been met. 20 Page 12 of 169 4.3.1.7. The heating and cooling loads have been calculated room-by-room, as documented in Section 4.2.4.4. 4.3.2. If a Dwelling Unit or Sleeping Unit not within a Dwelling or Townhouse is to be rated, and the maximum total heat gain across orientations documented in Section 4.2.4.17 is ≤18 kBtuh and the total heat loss documented in Section 4.2.4.19 is ≤35 kBtuh, then the following criteria shall be met in addition to the criteria in Section 4.3.4: 4.3.2.1. The name of the unique identifier for the building that the unit is within matches that used in the HVAC design, as documented in Section 4.2.2.4.2.1. 4.3.2.2. The name of the Architectural Plan of the unit meets one of the following conditions: 4.3.2.2.1. Matches that used in the HVAC design, as documented in Section 4.2.2.4.2.2. 4.3.2.2.2. Is included in the list of Architectural Plans that the HVAC design can be used with, as documented in Section 4.2.2.4.2.2, and the Architectural Plan used in the HVAC design has the largest Conditioned Floor Area among the plans listed. 4.3.2.3. Any Architectural Option(s) used in the unit meets one of the following conditions: 4.3.2.3.1. Match those used in the HVAC design, as documented in Section 4.2.2.4.2.3. 4.3.2.3.2. Are included in the list of Architectural Options that the HVAC design can be used with, as documented in Section 4.2.2.4.2.3, and the Architectural Options used in the HVAC design have the largest Conditioned Floor Area among the options listed. 4.3.2.4. The window area of each zone in the Dwelling Unit or Sleeping Unit is less than or equal to the area in the HVAC Design, as documented in Section 4.2.4.11. 4.3.2.5. The location of the unit meets one of the following conditions: 4.3.2.5.1. Matches that used in the HVAC design, as documented in Section 4.2.4.2 23 . 4.3.2.5.2. The unit location, as documented in Section 4.2.4.2, is the top floor and a corner unit. 4.3.2.6. Orientation-specific total heat gains have been documented for all eight orientations in Section 4.2.4.17. 4.3.3. If a Dwelling Unit or Sleeping Unit not within a Dwelling or Townhouse is to be rated, and the maximum total heat gain across orientations documented in Section 4.2.4.17 is >18 kBtuh or the total heat loss documented in Section 4.2.4.19 is >35 (Normative Note) The top floor, middle floor, or bottom floor and whether the unit is a corner unit or middle unit. 23 Page 13 of 169 kBtuh, then the following criteria shall be met in addition to the criteria in Section 4.3.4: 4.3.3.1. The name of the unique identifier for the building that the unit is within matches that used in the HVAC design, as documented in Section 4.2.2.4.2.1. 4.3.3.2. The name of the Architectural Plan of the unit matches that used in the HVAC design, as documented in Section 4.2.2.4.2.2. 4.3.3.3. Any Architectural Option(s) used in the unit match those used in the HVAC design or are included in the list of Architectural Option(s) that the design can be used with, as documented in Section 4.2.2.4.2.3. 4.3.3.4. The Conditioned Floor Area of each zone in the Dwelling Unit or Sleeping Unit is between 300 square feet smaller and 100 square feet larger than the area in the HVAC design, as documented in Section 4.2.4.10. 4.3.3.5. The window area of each zone in the Dwelling Unit or Sleeping Unit is between 60 square feet smaller and 15 square feet larger than the area in the HVAC Design, as documented in Section 4.2.4.11, or for zones with > 500 square feet of window area, between 12% smaller and 3% larger. 4.3.3.6. The Front Orientation of the Dwelling Unit or Sleeping Unit matches one of the orientations included in the orientation-specific heat gains documented in Section 4.2.4.17. 4.3.3.7. The difference between the maximum and minimum total heat gain for each zone, as documented in Section 4.2.4.18, is ≤ 6 kBtuh. 4.3.4. For all Dwellings, Townhouses, Dwelling Units, and Sleeping Units, the following criteria shall be met: 4.3.5. The indoor design temperatures used in the loads, as documented in Section 4.2.4.5, equals 70 °F (21 °C) for the heating season and 75 °F (24 °C) for the cooling season. 4.3.6. If the Dwelling is located in the U.S., then the cooling season and heating season outdoor design temperatures used in the loads, as documented in Section 4.2.4.6, shall not exceed the limits defined in Appendix A. 4.3.7. The number of occupants in the Dwelling, which shall be calculated using Equation 2, are within ± 2 of the sum of the occupants used in the loads across all zones, as documented in Section 4.2.4.7. 𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂 = 𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑜𝑜𝑜𝑜 𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵 + 1 (2) 4.3.8. The solar heat gain coefficient value used in the greatest amount of window area for each zone in the Dwelling is within ± 0.1 of the value used in the loads, as documented in Section 4.2.4.12. Page 14 of 169 4.3.9. The nominal R-value of the insulation 24 used in the greatest amount of abovegrade wall area for each zone in the Dwelling is within ± R-2 of the value used in the loads, as documented in Section 4.2.4.13. 4.3.10. The nominal R-value of the insulation used in the greatest amount of ceiling area for each zone in the Dwelling is within ± R-4 of the value used in the loads, as documented in Section 4.2.4.14. 4.3.11. If the infiltration design value is quantitative, then the infiltration rate of the Dwelling is within ± 2.0 ACH50 of the value used in the loads for each zone, as documented in Section 4.2.4.15. If the infiltration design value is qualitative, then the infiltration rate of the Dwelling is within the tolerance specified in Table 1 for the qualitative cooling infiltration input used in the design. Table 1 – Infiltration Tolerance of Dwelling Qualitative Cooling Infiltration Input Used in Design Infiltration Tolerance of Dwelling (ACH50) Tight Semi-Tight Average Semi-Leaky Leaky 0-4.0 1.0-5.0 3.0-7.0 7.0-11.0 >11.0 4.3.12. The sum of the design’s time-averaged mechanical Ventilation airflow rates across all Ventilation zones, as documented in Section 4.2.3.6.5, equals the sum used in the loads across all heated and cooled zones, as documented in Section 4.2.4.16. 4.3.13. Each HVAC System in the Dwelling serves the heated or cooled zone(s) documented in Section 4.2.5.2 25. 4.3.14. Each HVAC System in the Dwelling matches the equipment type specified in Section 4.2.5.3.1. 4.3.15. The sum of the design airflows across all rooms reported in Section 4.2.5.5.4 equals the mode with the higher design Blower Fan airflow, as reported in Section 4.2.5.5.1. 5. Task 2: Evaluation of the Total Duct Leakage. 5.1. Overview. This procedure shall be completed by first meeting the prerequisites in Section 5.2, then measuring the total duct leakage per Section 5.3, and finally designating the total duct leakage grade per Section 5.4. (Informative Note) If both cavity and continuous insulation are used, the nominal R-value equals the sum of nominal R-value of the cavity and continuous insulation. 25 (Informative Note) For example, if the design indicates that System A is intended to serve the “Upper Level” zone, then it shall be verified that System A does serve this zone. 24 Page 15 of 169 As an alternative to measuring the total duct leakage per Section 5.3, if an Independent Verification Report is obtained containing the measured total duct leakage of the ForcedAir HVAC System under test, and the report is approved for use by an entity adopting and requiring the use of this Standard, then the reported value shall be permitted to be used. If an Independent Verification Report is obtained, the reported value shall be used to designate the total duct leakage grade per Section 5.4. All procedures shall be performed by parties with proper training and using appropriate safety equipment. Equipment manufacturers’ operating instructions and safety instructions shall be followed. 5.2. Prerequisites. The HVAC design of the Dwelling shall have been evaluated in accordance with Section 4: all the required design documentation defined in Section 4.2 shall have been collected, and shall have been reviewed and verified to be in accordance with Section 4.3, or an Independent Verification Report obtained. If the design has not been evaluated, then the Forced-air HVAC System shall not be further evaluated using this standard, and Grade III shall be designated for total duct leakage, Blower Fan volumetric airflow, Blower Fan watt draw, and refrigerant charge. 5.3. Procedure to Measure Total Duct Leakage. The total duct leakage of the Forced-Air HVAC system under test shall be measured in accordance with ANSI/RESNET/ICC 380. The total duct leakage; time of test, either rough-in or final; and number of returns shall be recorded. Exception: If the total amount of supply ductwork or distribution building cavities does not exceed 10 ft. in length and is entirely in Conditioned Space Volume, then measurement of total duct leakage is not required 26. 5.4. Designating the Total Duct Leakage Grade 5.4.1. Grade I shall be designated and recorded for total duct leakage if the Forced-Air HVAC System has a total amount of supply ductwork or distribution building cavities that does not exceed 10 ft. in length and is entirely in Conditioned Space Volume, or if the total leakage does not exceed the limits in Table 2a or Table 2b. As an alternative, if the total duct leakage does not exceed the limits specified within ANSI/ACCA 5 QI Section 5.1.1a, then Grade I shall also be designated. Table 2a – Duct Leakage Limits for Grade I (IP) 26 Leakage Limit Time of Test # of Returns Rough-In <3 The greater of ≤ 4 per 100 ft2 of CFA or ≤ 40 Rough-In ≥3 The greater of ≤ 6 per 100 ft2 of CFA or ≤ 60 Final <3 The greater of ≤ 8 per 100 ft2 of CFA or ≤ 80 Final ≥3 The greater of ≤ 12 per 100 ft2 of CFA or ≤ 120 (CFM at 25 Pa) (Informative Note) Systems that fall under this exception receive a Grade I designation per Section 5.4. Page 16 of 169 Table 2b – Duct Leakage Limits for Grade I (SI) Time of Test Leakage Limit # of Returns (CMS at 0.001 IWC) Rough-In <3 The greater of ≤ 0.0019 per 9.29 m2 of CFA or ≤ 0.019 Rough-In ≥3 The greater of ≤ 0.0028 per 9.29 m2 of CFA or ≤ 0.028 Final <3 The greater of ≤ 0.0038 per 9.29 m2 of CFA or ≤ 0.038 Final ≥3 The greater of ≤ 0.0057 per 9.29 m2 of CFA or ≤ 0.057 5.4.2. Grade II shall be designated, and recorded, if the total leakage does not exceed the limits in Table 3a or Table 3b. Table 3a – Duct Leakage Limits for Grade II (IP) Leakage Limit # of Returns (CFM at 25 Pa) Time of Test Rough-In <3 The greater of ≤ 6 per 100 ft2 of CFA or ≤ 60 Rough-In ≥3 The greater of ≤ 8 per 100 ft2 of CFA or ≤ 80 Final <3 The greater of ≤ 10 per 100 ft2 of CFA or ≤ 100 Final ≥3 The greater of ≤ 14 per 100 ft2 of CFA or ≤ 140 Table 3b – Duct Leakage Limits for Grade II (SI) Time of Test Leakage Limit # of Returns (CMS at 0.001 IWC) Rough-In <3 The greater of ≤ 0.0028 per 9.29 m2 of CFA or ≤ 0.028 Rough-In ≥3 The greater of ≤ 0.0038 per 9.29 m2 of CFA or ≤ 0.038 Final <3 The greater of ≤ 0.0047 per 9.29 m2 of CFA or ≤ 0.047 Final ≥3 The greater of ≤ 0.0066 per 9.29 m2 of CFA or ≤ 0.066 5.4.3. Unless the exception in Section 5.3 has been met, Grade III shall be designated and recorded if the total duct leakage has been measured and exceeds the limits in Section 5.4.2. 6. Task 3: Evaluation of the Blower Fan Volumetric Airflow. 6.1. Overview. This procedure shall be completed by first meeting the prerequisites in Section 6.2, then determining the applicable test method per Section 6.3, then preparing the Dwelling and Forced-Air HVAC System for testing per Section 6.4, then measuring the Page 17 of 169 Blower Fan volumetric airflow using Section 6.5, 6.6, 6.7, or 6.8, and finally designating the Blower Fan Volumetric Airflow grade per Section 6.9. As an alternative to completing the procedures defined in Sections 6.5 through 6.8, if the installed equipment contains an on-board diagnostic system that is capable of reporting 27 the Blower Fan volumetric airflow and that is approved for use by an entity adopting and requiring the use of this Standard, then the reported value shall be permitted to be used. As an alternative to completing the procedures defined in Sections 6.3 through 6.8, if an Independent Verification Report is obtained containing the measured Blower Fan volumetric airflow of the Forced-Air HVAC System under test, and the report is approved for use by an entity adopting and requiring the use of this Standard, then the reported value shall be permitted to be used. If an on-board diagnostic system is used or Independent Verification Report is obtained, the reported value shall be used to designate the Blower Fan Volumetric Airflow grade per Section 6.9. As an alternative to completing the procedures defined in Sections 6.5 through 6.8, the following are approved for use: • Section 4.1.2 from ANSI/ACCA 5 QI, • Section 8.6 from ASTM E1554-13, • Normative Appendix A from ANSI/ASHRAE Standard 152-2004, • Section RA3.3 from the 2016 Reference Appendices for the 2016 Building Energy Efficiency Standards of the California Energy Commission. All procedures shall be performed by parties with proper training and using appropriate safety equipment. Equipment manufacturers’ operating instructions and safety instructions shall be followed. 6.2. Prerequisites. Prior to evaluating the Blower Fan volumetric airflow, all the following requirements shall have been met. 6.2.1. The total duct leakage shall have been evaluated in accordance with Section 5, including all prerequisites in Section 5.2. If the total duct leakage has been designated Grade III, then the Forced-air HVAC System shall not be further evaluated using this standard, and Grade III shall be designated for Blower Fan volumetric airflow, Blower Fan watt draw, and refrigerant charge. 6.2.2. Verification of HVAC Components. If the following components are included in the required design documentation for the Forced-Air HVAC System under test, they shall be verified to be present. If these components are not operational at the time of inspection, then the Forced-air HVAC System shall not be further evaluated using this standard, and Grade III shall be designated for Blower Fan volumetric airflow, Blower Fan watt draw, and refrigerant charge. The additional requirements defined in Section 6.2.2.1 shall also be met. (Informative Note) That is to say, capable of transmitting the relevant parameter to the user (e.g., on a thermostat screen, mobile phone). 27 Page 18 of 169 6.2.2.1. HVAC equipment. The specified manufacturer(s) and model number(s) of the equipment in the Forced-Air HVAC System under test matches the installed equipment or supplemental documentation has been collected as defined in Section 4.2.5 and verified in accordance with Section 4.3. If the installed equipment does not match the specified equipment in the original or supplemental documentation, then the Forced-air HVAC System shall not be further evaluated using this standard, and Grade III shall be designated for Blower Fan volumetric airflow, Blower Fan watt draw, and refrigerant charge. 6.2.2.2. Dwelling-Unit Mechanical Ventilation Systems integrated with the HVAC System. 6.2.2.3. Distribution systems, including supply registers and return grilles. 6.2.2.4. An air filter with the same performance rating and metric 28 as reported in Section 4.2.5.4. 29 6.3. Determination of Applicable Test Method. The test procedure used to evaluate the airflow shall be selected according to Sections 6.3.1.1 through 6.3.1.3. 6.3.1.1. If the Forced-Air HVAC System has a total amount of supply ductwork or distribution building cavities that does not exceed 10 ft. in length and is entirely in Conditioned Space Volume, then measurement of the airflow shall be exempted and the volumetric airflow grade shall be designated in accordance with Section 6.9. 6.3.1.2. If the Forced-Air HVAC System does not meet the conditions in Section 6.3.1.1 and the total duct leakage has been designated Grade I, the airflow is permitted to be measured using either the Pressure Matching Method (Section 6.5), a Flow Grid (Section 6.6), a Flow Hood (Section 6.7), or the OEM Static Pressure Table Method (Section 6.8) 30. 6.3.1.3. If the total duct leakage has been designated Grade II, the airflow is permitted to be measured using the Pressure Matching Method with Method 1 Installation (Section 6.5), a Flow Grid (Section 6.6), or the OEM Static Pressure Table Method (Section 6.8). 6.4. Procedure to Prepare the Dwelling and Forced-Air HVAC System 6.4

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