Controls — economizers, fan controls, hydronic controls and functional testing

Grounded in the retrieved California Energy Code — click a citation to read the verbatim passage:

• § 805.7.1.1 High relevance — show source text

  E 805.7.1.1 Construction Inspection. Prior to functional testing, verify and document the following:

  (1) Supply fan controls modulate to increase capacity.

  (2) Supply fan maintains discharge static pressure within plus or minus 10 percent of the current operating set point.

  (3) Supply fan controls stabilize within a 5 minute period.

  E 805.7.1.2 Functional Testing. The functional testing shall be in accordance with the following steps:

  Step 1: Simulate demand for design airflow. Verify and document the following:

  (1) Supply fan controls modulate to increase capacity.

  (2) Supply fan maintains discharge static pressure within plus or minus 10 percent of the current operating set point. (3) Supply fan controls stabilize within a 5 minute period. Step 2: Simulate demand for minimum airflow. Verify and document the following: (1) Supply fan controls modulate to decrease capacity. (2) Current operating setpoint has decreased (for systems with DDC to the zone level). (3) Supply fan maintains discharge static pressure within plus or minus 10 percent of the current operating setpoint. (4) Supply fan controls stabilize within a 5 minute period. Step 3: Restore system to correct operating conditions.

  E 805.7.2 Acceptance Criteria. Supply fan variable flow controls acceptance criteria shall be as follows: (1) Static pressure sensor(s) is factory calibrated (with calibration certificate) or field calibrated. (2) For systems without DDC controls to the zone level, the pressure sensor setpoint is less than one-third of the supply fan design static pressure.

  (3) For systems with DDC controls with VAV boxes reporting to the central control panel, the pressure setpoint is reset by zone demand (box damper position or a trim and respond algorithm).

  At full flow:

  (1) Supply fan maintains discharge static pressure within plus or minus 10 percent of the current operating control static pressure setpoint. (2) Supply fan controls stabilizes within a 5 minute period. (3) At minimum flow (not less than 30 percent of total design flow). (4) Supply fan controls modulate to decrease capacity. (5) Current operating setpoint has decreased (for systems with DDC to the zone level). (6) Supply fan maintains discharge static pressure within plus or minus 10 percent of the current operating setpoint. E 805.8 Valve Leakage (Form MECH-8A). The purpose of this test is to ensure that control valves serving variable flow systems are designed to withstand the pump pressure over the full range of operation. Valves with insufficient actuators will lift under certain conditions causing water to leak through and loss of control. This test applies to the variable flow systems, chilled and hot-water variable flow systems, chiller isolation valves, boiler isolation valves, and watercooled air conditioner and hydronic heat pump systems.

  E 805.8.1 Test Procedure. The procedure for performing a functional test for valve leakage shall be in accordance with Section E 805.8.1.1 and Section E

  805.8.1.2.

  E 805.8.1.1 Construction Inspection. Prior to functional testing, verify and document the valve and piping arrangements were installed in accordance with the design drawings. E 805.8.1.2 Functional Testing. The functional testing shall be in accordance with the following steps:

• § 5.1. High relevance — show source text

  (a) Before an occupancy permit is granted, the following equipment and systems shall be certified as meeting the Acceptance Requirements for Code Compliance, as specified by the Reference Nonresidential Appendix NA7. A Certificate of Acceptance shall be submitted to the enforcement agency that certifies that the equipment and systems meet the acceptance requirements:

  1. Outdoor air ventilation systems shall be tested in accordance with NA7.5.1.

  2. Constant volume, single zone unitary air conditioning and heat pump unit controls shall be tested in accordance with NA7.5.2.

  3. Duct systems that are subject to testing under Section 120.4(g)1, Section 141.0(b)2Di or Section 141.0(b)2Dii shall be tested in accordance with NA7.5.3.

  4. Air economizers, DOAS, HRV or ERV systems shall be tested in accordance with NA7.5.4. Exception 1 to Section 120.5(a)4: Air economizers installed by the HVAC system manufacturer and certified to the Commission as being factory calibrated and tested are not required to comply with the Functional Testing section of the air economizer controls acceptance test as described in NA7.5.4.2. Exception 2 to Section 120.5(a)4: The DOAS, HRV, or ERV unit that does not meet the exhaust air heat recovery ratio as specified in Section 140.4(q)1 or does not include bypass or control to disable energy recovery as specified in Section 140.4(q)2.

  5. Demand control ventilation systems required by Section 120.1(c)3 shall be tested in accordance with NA7.5.5.

  6. Supply fan variable flow controls shall be tested in accordance with NA7.5.6.

  7. Hydronic system variable flow controls shall be tested in accordance with NA7.5.7 and NA7.5.9.

  8. Boiler or chillers that require isolation controls as specified by Section 140.4(k)2 or 140.4(k)3 shall be tested in accordance with NA7.5.7.

  9. Hydronic systems with supply water temperature reset controls shall be tested in accordance with NA7.5.8.

  10. Automatic demand shed controls shall be tested in accordance with NA7.5.10.

  11. Fault Detection and Diagnostics (FDD) for Packaged Direct-Expansion Units shall be tested in accordance with NA7.5.11.

  12. Automatic fault detection and diagnostics (FDD) for air handling units and zone terminal units shall be tested in accordance with NA7.5.12.

  13. Distributed Energy Storage DX AC Systems shall be tested in accordance with NA7.5.13.

  14. Thermal Energy Storage (TES) Systems shall be tested in accordance with NA7.5.14.

  15. Supply air temperature reset controls shall be tested in accordance with NA7.5.15.

  16. Water-cooled chillers served by cooling towers with condenser water reset controls shall be tested in accordance with NA7.5.16.

  17. When an energy management control system is installed, it shall functionally meet all of the applicable requirements of Part 6.

  18. Occupant sensing zone controls shall be tested in accordance with NA7.5.17.

  19. Conductivity controls and overflow alarms for open and closed-circuit cooling towers shall be tested according to NA7.5.18.

• § 803.2.1.3 High relevance — show source text

  The responsible person shall perform the field testing and verification work, and where this is the case, the responsible person shall complete and sign both the field technician’s signature block and the responsible person’s signature block on the certificate of acceptance form. The responsible person assumes responsibility for the acceptance testing work performed by the field technician agent or employee. E 803.2.1.3 Certificate of Acceptance. The certificate of acceptance shall be submitted to the Authority Having Jurisdiction in order to receive the final certificate of occupancy. The Authority Having Jurisdiction shall not release a final certificate of occupancy unless the submitted certificate of acceptance demonstrates that the specified systems and equipment have been shown to be performing in accordance with the applicable acceptance requirements. The Authority Having Jurisdiction has the authority to require the field technician and responsible person to demonstrate competence, to its satisfaction. Certificate of acceptance forms are located in Section E 806.0.

  E 804.0 Commissioning Tests. E 804.1 General. Functional tests shall be performed on new equipment and systems installed in either new construction or retrofit applications in accordance with this section. The appropriate certificate of acceptance form along with each specific test shall be completed and submitted to the Authority Having Jurisdiction before a final occupancy permit can be granted.

  E 804.2 Tests. Functional testing shall be performed on the devices and systems listed in this section. The functional test results are documented using the applicable certificate of acceptance forms shown in parenthesis and located in Section E 806.0. The functional tests shall be performed in accordance with Section E 805.0 using the following forms:

  (1) Minimum ventilation controls for constant and variable air volume systems (Form MECH-2A).

  (2) Zone temperature and scheduling controls for constant volume, single-zone, unitary air conditioner and heat pump systems (Form MECH-3A).

  (3) Duct leakage on a subset of small single-zone systems depending on the ductwork location (Form MECH-4A).

  (4) Air economizer controls for economizers that are not factory installed and tested (Form MECH-5A).

  (5) Demand-controlled ventilation control systems (Form MECH-6A).

  (6) Supply fan variable flow controls (Form MECH-7A).

  (7) Valve leakage for hydronic variable flow systems and isolation valves on chillers and boilers in plants with more than one chiller or boiler being served by the same primary pumps through a common header (Form MECH8A).

  (8) Supply water temperature reset control strategies programmed into the building automation system for water systems (e.g., chilled, hot, or condenser water) (Form MECH-9A).

  (9) Hydronic variable flow controls on a water system where the pumps are controlled by variable frequency drives (e.g., chilled and hot water systems; water-loop heat pump systems) (Form MECH-10A).

  (10)Automatic demand shed control (Form MECH-11A).

  (11)Fault detection and diagnostic for DX units (Form MECH-12A).

  (12)Automatic fault detection and diagnostic systems (AFDD) (Form MECH-13A).

  (13)Distributed energy storage DEC/DX AC systems (Form MECH-14A).

  (14)Thermal energy storage (TES) systems (Form MECH15A). E 804.3 Acceptance Process. The functional testing process shall comply with Section E 804.3.1 through Section E 804.3.4.

• § 120.2 High relevance — show source text

  Exception 3 to Sections 120.2(e) 1 and 2: Systems serving hotel/motel guest rooms, if they have a readily accessible manual shut-off switch.

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  NONRESIDENTIAL, HOTEL/MOTEL OCCUPANCIES, AND COVERED PROCESSES—MANDATORY REQUIREMENTS

  4. Hotel and motel guest rooms shall have captive card key controls, occupancy sensing controls or automatic controls such that, no longer than 30 minutes after the guest room has been vacated, setpoints are set up at least +5°F (+3°C) in cooling mode and set down at least -5°F (-3°C) in heating mode.

  Exception to Section 120.2(e): Systems serving healthcare facilities.

  (f) Dampers for air supply and exhaust equipment. Outdoor air supply and exhaust equipment shall be installed with dampers that automatically close upon fan shutdown.

  Exception 1 to Section 120.2(f): Equipment that serves an area that must operate continuously.

  Exception 2 to Section 120.2(f): Gravity and other nonelectrical equipment that has readily accessible manual damper controls.

  Exception 3 to Section 120.2(f): At combustion air intakes and shaft vents.

  Exception 4 to Section 120.2(f): Where prohibited by other provisions of law.

  (g) Isolation area devices. Each space-conditioning system serving multiple zones with a combined conditioned floor area of more than 25,000 square feet shall be designed, installed and controlled to serve isolation areas.

  1. Each zone, or any combination of zones not exceeding 25,000 square feet, shall be a separate isolation area.
  2. Each isolation area shall be provided with isolation devices, such as valves or dampers, that allow the supply of heating or cooling to be reduced or shut off independently of other isolation areas.
  3. Each isolation area shall be controlled by a device meeting the requirements of Section 120.2(e)1.

  Exception to Section 120.2(g): Zones designed to be conditioned continuously.

  (h) Automatic demand shed controls. See Section 110.12 for requirements for automatic demand shed controls.

  (i) Economizer fault detection and diagnostics (FDD). All newly installed air handlers with a mechanical cooling capacity over 33,000 Btu/hr and an installed air economizer shall include a stand-alone or integrated Fault Detection and Diagnostics (FDD) system in accordance with Subsections 120.2(i)1 through 120.2(i)8.

  1. The following temperature sensors shall be permanently installed to monitor system operation: outside air, supply air, and when required for differential economizer operation a return air sensor, and
  2. Temperature sensors shall have an accuracy of ±2°F over the range of 40°F to 80°F; and
  3. The controller shall have the capability of displaying the value of each sensor; and
  4. The controller shall provide system status by indicating the following conditions: A. Free cooling available; B. Economizer enabled;

  C. Compressor enabled; D. Heating enabled, if the system is capable of heating; and E. Mixed-air low limit cycle active. 5. The unit controller shall allow manual initiation of each operating mode so that the operation of cooling systems, economizers, fans and heating system can be independently tested and verified; and 6. Faults shall be reported in one of the following ways: A. Reported to an Energy Management Control System regularly monitored by facility personnel.

• § 160.3 High relevance — show source text

  (d) Mechanical acceptance testing.

  1. Common areas. Before an occupancy permit is granted, the following systems and equipment serving multifamily common areas shall be certified as meeting the Acceptance Requirements for Code Compliance, as specified by Reference Nonresidential Appendix NA7. These systems and equipment shall also comply with the applicable requirements of Section

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  160.3(d)3. A Certificate of Acceptance shall be submitted to the enforcement agency that certifies that the equipment and systems meet the acceptance requirements: A. Outdoor air ventilation systems shall be tested in accordance with NA7.5.1. B. Constant volume, single zone air conditioning and heat pump unit controls shall be tested in accordance with NA7.5.2. C. Duct systems shall be tested in accordance with NA7.5.3 where either: a. They are new duct systems; or b. They are part of an altered system. D. Air economizers, DOAS, HRV or ERV systems shall be tested in accordance with NA7.5.4. Exception to Section 160.3(d)1D: Air economizers installed by the HVAC system manufacturer and certified to the Commission as being factory calibrated and tested are not required to comply with the Functional Testing section of the Air Economizer Controls acceptance test as described in NA7.5.4.2. E. Demand control ventilation systems required by Section 160.2(c)3 shall be tested in accordance with NA7.5.5. F. Supply fan variable flow controls shall be tested in accordance with NA7.5.6. G. Hydronic system variable flow controls shall be tested in accordance with NA7.5.7 and NA7.5.9. H. Boilers or chillers that require isolation controls as specified by Section 170.2(c)4Iii or 170.2(c)4Iiii shall be tested in accordance with NA7.5.7.

  I. Hydronic systems with supply water temperature reset controls shall be tested in accordance with NA7.5.8.

  J. Automatic demand shed controls shall be tested in accordance with NA7.5.10.

  K. Fault detection and diagnostics (FDD) for packaged direct expansion units shall be tested in accordance with NA7.5.11. L. Automatic fault detection and diagnostics (FDD) for air handling units and zone terminal units shall be tested in accordance with NA7.5.12.

  M. Distributed energy storage DX AC systems shall be tested in accordance with NA7.5.13. N. Thermal energy storage (TES) systems shall be tested in accordance with NA7.5.14. O. Supply air temperature reset controls shall be tested in accordance with NA7.5.15. P. Water-cooled chillers served by cooling towers with condenser water reset controls shall be tested in accordance with NA7.5.16.

  Q. When an energy management control system is installed, it shall functionally meet all of the applicable requirements of Part 6.

• § 805.4.2 High relevance — show source text

  E 805.4.2 Acceptance Criteria. Flexible ducts are not compressed or constricted. Duct connections shall comply with the requirements of this appendix and this code (new ducts only). Joints and seams are properly sealed in accordance with the requirements of this appendix and this code (new ducts only). Duct R-values shall comply with the minimum requirements of this appendix (new ducts only). Insulation is protected from damage and suitable for outdoor usage where applicable (new ducts only). The leakage shall not exceed the rate in accordance with Section E 503.4.7.2.1.

  E 805.5 Air Economizer Controls Acceptance (Form MECH-5A). The purpose of functionally testing an air economizer cycle is to verify that an HVAC system uses outdoor air to satisfy space cooling loads where outdoor air conditions are acceptable. There are two types of economizer controls; stand-alone packages and DDC controls. The stand-alone packages are commonly associated with small unitary rooftop HVAC equipment, and DDC controls are typically associated with built-up or large packaged air handling systems. Test procedures for both economizer control types are provided.

  For units with economizers that are factory installed and certified operational by the manufacturer to economizer quality control requirements, the in-field economizer functional tests do not have to be conducted. A copy of the manufacturer’s certificate shall be attached to the Form MECH-5A. However, the construction inspection, including compliance with high-temperature lockout temperature setpoint, shall be completed regardless of whether the economizer is field or factory installed.

  E 805.5.1 Test Procedure. The procedure for performing a functional test for air economizer controls shall comply with Section E 805.5.1.1 and Section E 805.5.1.2.

  E 805.5.1.1 Construction Inspection. Prior to functional testing, verify and document the following:

  (1) Economizer lockout setpoint is in accordance with this appendix.

  (2) Economizer lockout control sensor is located to prevent false readings.

  (3) System is designed to provide up to 100 percent outside air without over-pressurizing the building.

  (4) For systems with DDC controls lockout sensor(s) are either factory calibrated or field calibrated.

  (5) For systems with non-DDC controls, manufacturer’s startup and testing procedures are applied.

  E 805.5.1.2 Functional Testing. The functional testing shall be in accordance with the following steps:

  Step 1: Disable demand control ventilation systems (where applicable).

  Step 2: Enable the economizer, and simulate a cooling demand large enough to drive the economizer fully open. Verify and document the following:

  (1) Economizer damper is 100 percent opened and return air damper is 100 percent closed.

  (2) Where applicable, verify that the economizer remains 100 percent open where the cooling demand can no longer be met by the economizer alone.

  (3) Applicable fans and dampers operate as intended to maintain building pressure.

  (4) The unit heating is disabled.

  Step 3: Disable the economizer and simulate a cooling demand. Verify and document the following:

  (1) Economizer damper shall close to its minimum position.

  (2) Applicable fans and dampers shall operate as intended to maintain building pressure.

  (3) The unit heating is disabled.

• § 110.12 High relevance — show source text

  ** See Section 110.12 for requirements for automatic demand shed controls. H. Economizer fault detection and diagnostics (FDD). All newly installed air handlers with a mechanical cooling capacity over 33,000 Btu/hr and an installed air economizer shall include a stand-alone or integrated fault detection and diagnostics (FDD) system in accordance with Subsections 160.3(a)2Hi through 160.3(a)2Hviii. i. The following temperature sensors shall be permanently installed to monitor system operation: outside air, supply air and, when required for differential economizer operation, a return air sensor; and ii. Temperature sensors shall have an accuracy of ±2°F over the range of 40°F to 80°F; and iii. The controller shall have the capability of displaying the value of each sensor; and iv. The controller shall provide system status by indicating the following conditions: a. Free cooling available; b. Economizer enabled;

  c. Compressor enabled; d. Heating enabled, if the system is capable of heating; and e. Mixed air low limit cycle active. v. The unit controller shall allow manual initiation of each operating mode so that the operation of cooling systems, economizers, fans and heating systems can be independently tested and verified; and vi. Faults shall be reported in one of the following ways: a. Reported to an energy management control system regularly monitored by facility personnel. b. Annunciated locally on one or more zone thermostats, or a device within 5 feet of zone thermostat(s), clearly visible, at eye level and meeting the following requirements:

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  I. On the thermostat, the device or an adjacent written sign, display instructions to contact appropriate building personnel or an HVAC technician; and II. In buildings with multiple tenants, the annunciation shall either be within property management offices or in a common space accessible by the property or building manager. c. Reported to a fault management application that automatically provides notification of the fault to remote HVAC service provider. vii. The FDD system shall detect the following faults: a. Air temperature sensor failure/fault; b. Not economizing when it should; c. Economizing when it should not; d. Damper not modulating; and

  e. Excess outdoor air.

  viii. The FDD system shall be certified to the Energy Commission as meeting the requirements of Sections 160.3(a)2Hi through 160.3(a)2Hvii in accordance with Section 110.0 and JA6.3. Exception to Section 160.3(a)2Hviii: FDD algorithms based in direct digital control systems are not required to be certified to the Energy Commission. I. Direct digital controls (DDC). Direct digital controls to the zone shall be provided as specified by Table 160.3-C. i. The provided DDC system shall meet the control logic requirements of Sections 160.3(a)2E and 160.3(a)2G, and be capable of the following: ii. Monitoring zone and system demand for fan pressure, pump pressure, heating and cooling; iii. Transferring zone and system demand information from zones to air distribution system controllers and from air distribution systems to heating and cooling plant controllers; iv. Automatically detecting the zones and systems that may be excessively driving the reset logic and generate an alarm or other indication to the system operator; v. Readily allow operator removal of zone(s) from the reset algorithm; vi.

• § 120.2 Medium relevance — show source text

  Exception to Section 120.2(g): Zones designed to be conditioned continuously.

  (h) Automatic demand shed controls. See Section 110.12 for requirements for automatic demand shed controls.

  (i) Economizer fault detection and diagnostics (FDD). All newly installed air handlers with a mechanical cooling capacity over 33,000 Btu/hr and an installed air economizer shall include a stand-alone or integrated Fault Detection and Diagnostics (FDD) system in accordance with Subsections 120.2(i)1 through 120.2(i)8.

  1. The following temperature sensors shall be permanently installed to monitor system operation: outside air, supply air, and when required for differential economizer operation a return air sensor, and
  2. Temperature sensors shall have an accuracy of ±2°F over the range of 40°F to 80°F; and
  3. The controller shall have the capability of displaying the value of each sensor; and
  4. The controller shall provide system status by indicating the following conditions: A. Free cooling available; B. Economizer enabled;

  C. Compressor enabled; D. Heating enabled, if the system is capable of heating; and E. Mixed-air low limit cycle active. 5. The unit controller shall allow manual initiation of each operating mode so that the operation of cooling systems, economizers, fans and heating system can be independently tested and verified; and 6. Faults shall be reported in one of the following ways: A. Reported to an Energy Management Control System regularly monitored by facility personnel. B. Annunciated locally on one or more zone thermostats, or a device within five (5) feet of zone thermostat(s), clearly visible, at eye level, and meeting the following requirements: i. On the thermostat, device, or an adjacent written sign, display instructions to contact appropriate building personnel or an HVAC technician; and ii. In buildings with multiple tenants, the annunciation shall either be within property management offices or in a common space accessible by the property or building manager. C. Reported to a fault management application which automatically provides notification of the fault to a remote HVAC service provider. 7. The FDD system shall detect the following faults: A. Air temperature sensor failure/fault; B. Not economizing when it should; C. Economizing when it should not; D. Damper not modulating; and

  E. Excess outdoor air.

  8. The FDD System shall be certified to the Energy Commission as meeting requirements of Subsections 120.2(i)1 through 120.2(i)7 in accordance with Section 110.0 and JA6.3. Exception to Section 120.2(i)8: FDD algorithms based in direct digital control systems are not required to be certified to the Energy Commission.

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  NONRESIDENTIAL, HOTEL/MOTEL OCCUPANCIES, AND COVERED PROCESSES—MANDATORY REQUIREMENTS

  (j) Direct Digital Controls (DDC) . Direct Digital Controls to the zone shall be provided as specified by Table 120.2-A. The provided DDC system shall meet the control logic requirements of Sections 120.1(d), 110.12(a) and 110.12(b), and be capable of the following:

  The provided DDC system shall meet the control logic requirements of Sections 110.12(a), 110.12(b) and 120.1(d) and be capable of the following:

  1. Monitoring zone and system demand for fan pressure, pump pressure, heating and cooling;
• § 804.3 Medium relevance — show source text

  (3) Duct leakage on a subset of small single-zone systems depending on the ductwork location (Form MECH-4A).

  (4) Air economizer controls for economizers that are not factory installed and tested (Form MECH-5A).

  (5) Demand-controlled ventilation control systems (Form MECH-6A).

  (6) Supply fan variable flow controls (Form MECH-7A).

  (7) Valve leakage for hydronic variable flow systems and isolation valves on chillers and boilers in plants with more than one chiller or boiler being served by the same primary pumps through a common header (Form MECH8A).

  (8) Supply water temperature reset control strategies programmed into the building automation system for water systems (e.g., chilled, hot, or condenser water) (Form MECH-9A).

  (9) Hydronic variable flow controls on a water system where the pumps are controlled by variable frequency drives (e.g., chilled and hot water systems; water-loop heat pump systems) (Form MECH-10A).

  (10)Automatic demand shed control (Form MECH-11A).

  (11)Fault detection and diagnostic for DX units (Form MECH-12A).

  (12)Automatic fault detection and diagnostic systems (AFDD) (Form MECH-13A).

  (13)Distributed energy storage DEC/DX AC systems (Form MECH-14A).

  (14)Thermal energy storage (TES) systems (Form MECH15A). E 804.3 Acceptance Process. The functional testing process shall comply with Section E 804.3.1 through Section E 804.3.4.

  E 804.3.1 Plan Review. The installing contractor, registered design professional of record, owner’s agent, or the person responsible for certification of the acceptance testing on the certificate of acceptance (responsible person) shall review the plans and specifications to ensure that they are in accordance with the acceptance requirements. This is typically done prior to signing a certificate of compliance. E 804.3.2 Construction Inspection. The installing contractor, registered design professional of record, owner’s agent, or the person responsible for certification of the acceptance testing on the certificate of acceptance (responsible person) shall perform a construction inspection prior to testing to ensure that the equipment that is installed is capable of complying with the requirements of this appendix and is calibrated. The installation of associated systems and equipment necessary for proper system operation is required to be completed prior to the testing.

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  APPENDIX E

  E 804.3.3 Acceptance Testing. One or more field technicians shall perform the acceptance testing; identify performance deficiencies; ensure that they are corrected; and where necessary, repeat the acceptance procedures until the specified systems and equipment are performing in accordance with the acceptance requirements. The field technician who performs the testing shall sign the certificate of acceptance to certify the information has been provided to document the results of the acceptance procedures is true and correct.

  The responsible person shall review the test results from the acceptance requirement procedures provided by the field technician and sign the certificate of acceptance to certify compliance with the acceptance requirements. The responsible person shall be permitted to perform the field technician’s responsibilities, and shall then sign the field technician declaration on the certificate of acceptance to certify that the information on the form is true and correct.

• § 5.3 Medium relevance — show source text

  (g) Duct sealing. Duct systems shall comply with Subsection 1 or 2 below:

  1. New duct systems that meet the criteria in Subsections A, B, C and D below shall be sealed to a leakage rate not to exceed 6 percent of the nominal air handler airflow rate as confirmed through acceptance testing, in accordance with Reference Nonresidential Appendix NA7.5.3; A. The duct system does not serve a healthcare facility; and B. The duct system provides conditioned air to an occupiable space for a constant volume, single zone, space-conditioning system; and C. The space-conditioning system serves less than 5,000 square feet of conditioned floor area; and D. The combined surface area of the ducts located outdoors or in unconditioned space is more than 25 percent of the total surface area of the entire duct system.
  2. New duct systems that are not subject to testing under Section 120.4(g)1 shall instead meet the duct leakage testing requirements of CMC Section 603.9.2.

  Note: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code. Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.8, and 25943, Public Resources Code.

  SECTION 120.5—REQUIRED NONRESIDENTIAL MECHANICAL SYSTEM ACCEPTANCE

  Nonresidential and hotel/motel buildings shall comply with the applicable requirements of Sections 120.5(a) through 120.5(b).

  Exception to Section 120.5: Systems serving healthcare facilities.

  (a) Before an occupancy permit is granted, the following equipment and systems shall be certified as meeting the Acceptance Requirements for Code Compliance, as specified by the Reference Nonresidential Appendix NA7. A Certificate of Acceptance shall be submitted to the enforcement agency that certifies that the equipment and systems meet the acceptance requirements:

  1. Outdoor air ventilation systems shall be tested in accordance with NA7.5.1.

  2. Constant volume, single zone unitary air conditioning and heat pump unit controls shall be tested in accordance with NA7.5.2.

  3. Duct systems that are subject to testing under Section 120.4(g)1, Section 141.0(b)2Di or Section 141.0(b)2Dii shall be tested in accordance with NA7.5.3.

  4. Air economizers, DOAS, HRV or ERV systems shall be tested in accordance with NA7.5.4. Exception 1 to Section 120.5(a)4: Air economizers installed by the HVAC system manufacturer and certified to the Commission as being factory calibrated and tested are not required to comply with the Functional Testing section of the air economizer controls acceptance test as described in NA7.5.4.2. Exception 2 to Section 120.5(a)4: The DOAS, HRV, or ERV unit that does not meet the exhaust air heat recovery ratio as specified in Section 140.4(q)1 or does not include bypass or control to disable energy recovery as specified in Section 140.4(q)2.

  5. Demand control ventilation systems required by Section 120.1(c)3 shall be tested in accordance with NA7.5.5.

  6. Supply fan variable flow controls shall be tested in accordance with NA7.5.6.
• § 805.7 Medium relevance — show source text

  (5) A minimum OSA setting is provided where the system is in occupied mode in accordance with this appendix regardless of space carbon dioxide readings.

  (6) A maximum OSA damper position for DCV control shall be established in accordance with this appendix, regardless of space carbon dioxide readings.

  (7) The outdoor air damper shall modulate open where the carbon dioxide concentration within the space exceeds setpoint.

  (8) The outdoor air damper modulates closed (toward minimum position) where the carbon dioxide concentration within the space is below setpoint.

  E 805.7 Supply Fan Variable Flow Controls (Form MECH-7A). The purpose of this test is to ensure that the supply fan in a variable air volume application modulates to meet system airflow demand. In most applications, the individual VAV boxes serving each space will modulate the amount of

  2025 CALIFORNIA MECHANICAL CODE 485

  ), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

  APPENDIX E

  air delivered to the space based on heating and cooling requirements. As a result, the total supply airflow provided by the central air handling unit shall vary to maintain sufficient airflow through each VAV box. Airflow shall be controlled using a variable frequency drive (VFD) to modulate supply fan speed and vary system airflow. The most common strategy for controlling the VFD is to measure and maintain static pressure within the duct.

  E 805.7.1 Test Procedure. The procedure for performing a functional test for supply fan variable controls shall be in accordance with Section E 805.7.1.1 and Sec tion E 805.7.1.2.

  E 805.7.1.1 Construction Inspection. Prior to functional testing, verify and document the following:

  (1) Supply fan controls modulate to increase capacity.

  (2) Supply fan maintains discharge static pressure within plus or minus 10 percent of the current operating set point.

  (3) Supply fan controls stabilize within a 5 minute period.

  E 805.7.1.2 Functional Testing. The functional testing shall be in accordance with the following steps:

  Step 1: Simulate demand for design airflow. Verify and document the following:

  (1) Supply fan controls modulate to increase capacity.

  (2) Supply fan maintains discharge static pressure within plus or minus 10 percent of the current operating set point. (3) Supply fan controls stabilize within a 5 minute period. Step 2: Simulate demand for minimum airflow. Verify and document the following: (1) Supply fan controls modulate to decrease capacity. (2) Current operating setpoint has decreased (for systems with DDC to the zone level). (3) Supply fan maintains discharge static pressure within plus or minus 10 percent of the current operating setpoint. (4) Supply fan controls stabilize within a 5 minute period. Step 3: Restore system to correct operating conditions.

  E 805.7.2 Acceptance Criteria. Supply fan variable flow controls acceptance criteria shall be as follows: (1) Static pressure sensor(s) is factory calibrated (with calibration certificate) or field calibrated. (2) For systems without DDC controls to the zone level, the pressure sensor setpoint is less than one-third of the supply fan design static pressure.

• § 805.7 Medium relevance — show source text

  • I will ensure that a completed, signed copy of this Certificate of Acceptance shall be posted, or made available with the building permit(s) issued for the building, and made available to the enforcement agency for all applicable inspections. I understand that a signed copy of this Certificate of Acceptance is required to be included with the documentation the builder provides to

  the building owner at occupancy.	Col2	Col3	Col4
  Company Name:	Company Name:	Company Name:	Phone:
  Responsible Person’s Name:	Responsible Person’s Name:	Responsible Person’s Signature:	Responsible Person’s Signature:
  License:	Date Signed:	Position With Company (Title):	Position With Company (Title):

  508 2025 CALIFORNIA MECHANICAL CODE

  ), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

  APPENDIX E

  CERTIFICATE OF ACCEPTANCE MECH-7A	Col2
  Supply Fan VFD Acceptance (Page 2 of 2)	Supply Fan VFD Acceptance (Page 2 of 2)
  Project Name/Address:	Project Name/Address:
  System Name or Identification/Tag:	System Location or Area Served:

  Intent: Verify that the supply fan in a variable air volume application modulates to meet system airflow demand.

  Construction Inspection

  1 Instrumentation to perform test includes, but not limited to: a. Calibrated differential pressure gauge. 2 Installation.  Discharge static pressure sensors are either factory calibrated or field-calibrated.

   The static pressure location, setpoint, and reset control meets the requirements of Section E 805.7 through Section E 805.7.2.

  3 Documentation of all discharge static pressure sensors including (check one of the following):  Field-calibrated.

   Calibration complete, all pressure sensors within 10% of calibrated reference sensor.

  A. Functional Testing.	Col2	Results
  Step 1: Drive all VAV boxes to achieve design airflow.	Step 1: Drive all VAV boxes to achieve design airflow.	Step 1: Drive all VAV boxes to achieve design airflow.
  a. Supply fan controls modulate to increase capacity.	a. Supply fan controls modulate to increase capacity.	Y / N
  b. Supply fan maintains discharge static pressure within +/-10% of the current operating setpoint.	b. Supply fan maintains discharge static pressure within +/-10% of the current operating setpoint.	Y / N
  c. Supply fan controls stabilize within a 5 minute period.	c. Supply fan controls stabilize within a 5 minute period.	Y / N
  Step 2: Drive all VAV boxes to minimum flow.	Step 2: Drive all VAV boxes to minimum flow.	Step 2: Drive all VAV boxes to minimum flow.
  a. Supply fan controls modulate to decrease capacity.	a. Supply fan controls modulate to decrease capacity.	Y / N
  b. Current operating setpoint has decreased (for systems with DDC to the zone level).	b.