Controls, labeling, and workmanship

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

• CMC § 307.4 Medium relevance — show source text

  (11)Required clearances from combustible surfaces on which or adjacent to which it is permitted to be mounted.

  An appliance shall be accompanied by clear and complete installation instructions, including required clearances from combustible other than mounting or adjacent surfaces, and temperature rating of field-installed wiring connections exceeding 140°F (60°C). 307.4 Absorption Units. Absorption units shall bear a permanent and legible factory-applied nameplate on which shall

  appear:

  (1) The name or trademark of the manufacturer.

  (2) The model number or equivalent.

  (3) The serial number.

  (4) The amount of refrigerant.

  (5) The refrigerant designation.

  (6) Hourly rating in Btu/h (kW).

  (7) The type of fuel approved for use with the unit.

  (8) Cooling capacity Btu/h (kW).

  (9) Required clearances from combustible surfaces on which or adjacent to which it is permitted to be mounted.

  (10)The symbol of an approved agency certifying compliance of the equipment with recognized standards.

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  GENERAL REGULATIONS

  308.0 Improper Location.

  308.1 General. Piping or equipment shall not be so located as to interfere with the normal use thereof or with the normal operation and use of windows, doors, or other required facilities.

  309.0 Workmanship.

  309.1 Engineering Practices. Design, construction, and workmanship shall comply with accepted engineering practices and shall be of such character as to secure the results sought to be obtained by this code.

  309.2 Concealing Imperfections. It shall be unlawful to conceal cracks, holes, or other imperfections in materials by welding, brazing, or soldering, by using therein or thereon paint, wax, tar, solvent cement, other leak-sealing or repair agent.

  309.3 Installation Practices. Mechanical systems shall be installed in a manner that is in accordance with this code, applicable standards, and the manufacturer’s installation instructions. All mechanical systems shall be in accordance with construction documents approved by the Authority Having Jurisdiction.

  310.0 Condensate Wastes and Control.

  310.1 Condensate Disposal. Condensate from air washers, air-cooling coils, condensing appliances, and the overflow from evaporative coolers and similar water-supplied equipment or similar air-conditioning equipment shall be collected and discharged to an approved plumbing fixture or disposal area. Where discharged into the drainage system, equipment shall drain by means of an indirect waste pipe. The waste pipe shall have a slope of not less than [1] ⁄ 8 inch per foot (10.4 mm/m) or 1 percent slope and shall be of approved corrosion-resistant material not smaller than the outlet size in

  accordance with Section 310.3 or Section 310.4 for air-cooling coils or condensing appliances, respectively. Condensate or wastewater shall not drain over a public way.

• CMC § 104.5 Medium relevance — show source text

  INDEX

  © 2024 International Association of Plumbing and Mechanical Officials. All rights reserved. The copyright in this index is separate and distinct from the copyright in the document that it indexes. The licensing provisions set forth for the document are not applicable to this index. This index may not be reproduced in whole or in part by any means without the express written permission of IAPMO.

  – A –

  ABSORPTION SYSTEM

  Cooling system . . . . . . . . . . . . . . . . . . . . . . . Chapter 11 Duct system . . . . . . . . . . . . . . . . . . . . . . . . . . Chapter 6

  Permit Fees . . . . . . . . . . . . . . . . . . . . . . . . . Table 104.5

  ABSORPTION UNIT

  Definition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203.0

  Labeling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307.4

  Permit Fees . . . . . . . . . . . . . . . . . . . . . . . . . Table 104.5

  ACCEPTED ENGINEERING

  PRACTICE . . . . . . . . . . . . . . . . . . . . . . . . . . . 203.0, 309.1

  Oil supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D 112.1

  Definition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203.0

  HVAC system balancing . . . . . . . . . . . . . . . E 503.6.5.3

  Pump head . . . . . . . . . . . . . . . . . . . . . . . . . E 503.4.5.1

  Workmanship . . . . . . . . . . . . . . . . . . . . . . . . . . . . 309.1

  ACCESS PANELS

  Air handling units . . . . . . . . . . . . . . . . . . . . . . . 1106.2.3

  Appliances on roofs . . . . . . . . . . . . . . . . . . . . . . . 303.8

  Definition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203.0

  Ducts connected to

  duct furnaces . . . . . . . . . . . . . . . . . . . . . . . . . . 905.4

  Exhaust systems,

  commercial kitchen . . . . . . . . . . . . . 510.1.5, 510.3.1,

  510.3.6-510.3.7,

  510.7.7, 514.4.9, 514.4.10

  Exhaust systems, dryers (multistory) . . . . . . . . .504.4.6

• CMC § 305.6 Medium relevance — show source text

  305.6 Outdoor Locations . . . . . . . . . . . . . 55

  306.0 Automatic Control Devices . . . . . . . 55

  306.1 General. . . . . . . . . . . . . . . . . . . . . . 55

  306.2 Building Automation Systems . . . . 56

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  TABLE OF CONTENTS

  307.0 Labeling . . . . . . . . . . . . . . . . . . . . . 56

  307.1 Fuel-Burning Appliances . . . . . . . . 56

  307.2 Electric Heating Appliances . . . . . . 56

  307.3 Heat Pump and Electric Cooling Appliances . . . . . . . . . . . . . . . . . . . 56

  307.4 Absorption Units . . . . . . . . . . . . . . . 56

  308.0 Improper Location. . . . . . . . . . . . . . 57

  308.1 General. . . . . . . . . . . . . . . . . . . . . . 57

  309.0 Workmanship . . . . . . . . . . . . . . . . . 57

  309.1 Engineering Practices. . . . . . . . . . . 57

  309.2 Concealing Imperfections . . . . . . . . 57

  309.3 Installation Practices. . . . . . . . . . . . 57

  310.0 Condensate Wastes and Control . . 57

  310.1 Condensate Disposal . . . . . . . . . . . 57

  310.2 Condensate Control . . . . . . . . . . . . 57

  310.3 Condensate Waste Pipe Material and Sizing. . . . . . . . . . . . . . . . . . . . 57

  Table 310.3 Minimum Condensate Pipe Size. . . 57

  310.4 Appliance Condensate Drains . . . . 58

  310.5 Point of Discharge . . . . . . . . . . . . . 58

  310.6 Condensate Waste from

  Air-Conditioning Coils . . . . . . . . . . . 58

  310.7 Female Plastic Connections . . . . . . 58

  311.0 Heating or Cooling Air System . . . . 58

  311.1 Source . . . . . . . . . . . . . . . . . . . . . . 58

  311.2 Air Filters . . . . . . . . . . . . . . . . . . . . 58

  311.3 Prohibited Sources . . . . . . . . . . . . . 58

  311.4 Return-Air Limitations . . . . . . . . . . . 58

  311.5 California Energy Code Requirements for Residential

  Air Filtration . . . . . . . . . . . . . . . . . . 59

  312.0 Plumbing Connections . . . . . . . . . . 59

  312.1 General. . . . . . . . . . . . . . . . . . . . . . 59

• CMC § 1708.1 Medium relevance — show source text

  1708.1 General. . . . . . . . . . . . . . . . . . . . . 352

  1708.2 Operation and Maintenance Manual . . . . . . . . . . . . . . . . . . . . . 352

  1708.3 Labeling and Marking . . . . . . . . . . 352

  1708.4 Documentation . . . . . . . . . . . . . . . 352

  1708.5 Maintenance . . . . . . . . . . . . . . . . . 352

  1708.6 Records . . . . . . . . . . . . . . . . . . . . 352

  1708.7 System Start-Up . . . . . . . . . . . . . . 352

  1708.8 Contaminants . . . . . . . . . . . . . . . . 352

  1709.0 Decommissioning and Abandonment . . . . . . . . . . . . . . . . 352

  1709.1 General. . . . . . . . . . . . . . . . . . . . . 352

  Part II Closed-Loop Systems . . . . . . . . 352

  1710.0 General. . . . . . . . . . . . . . . . . . . . . 352

  1710.1 Applicability. . . . . . . . . . . . . . . . . . 352

  1710.2 Piping and Tubing. . . . . . . . . . . . . 352

  1710.3 Borehole Piping and Tubing . . . . . 352

  1710.4 Underground Fittings . . . . . . . . . . 352

  1710.5 Verification . . . . . . . . . . . . . . . . . . 353

  1710.6 Vertical Bores . . . . . . . . . . . . . . . . 353

  1711.0 Ground-Heat Exchanger Testing . . . . . . . . . . . . . . . . . . . . . 353

  1711.1 Testing . . . . . . . . . . . . . . . . . . . . . 353

  1711.2 Individual Loop Pressure Testing . . . . . . . . . . . . . . . . . . . . . 353

  1711.3 Field Pressure Testing – Final . . . 353

  1711.4 Field Flow Testing – Final. . . . . . . 353

  Part III Open-Loop Systems . . . . . . . . . . 353

  1712.0 General. . . . . . . . . . . . . . . . . . . . . 353

  1712.1 Applicability. . . . . . . . . . . . . . . . . . 353

  1712.2 Test Wells. . . . . . . . . . . . . . . . . . . 353

  1712.3 Installation of Water Wells . . . . . . 354

  1712.4 Setbacks. . . . . . . . . . . . . . . . . . . . 354

  1713.0 Open Ground Water Systems . . . 354

  1713.1 General. . . . . . . . . . . . . . . . . . . . . 354

• CMC § 90.1 Medium relevance — show source text

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  APPENDIX E

  to permit a determination of compliance by the building official and to indicate compliance with the requirements of this appendix. [ASHRAE 90.1:4.2.2.1] E 503.6.2 Supplemental Information. Supplemental information necessary to verify compliance with this appendix, such as calculations, worksheets, compliance forms, vendor literature, or other data, shall be made available where required by the Authority Having Jurisdiction. [ASHRAE 90.1:4.2.2.2]

  E 503.6.3 Manuals. Operating and maintenance information shall be provided to the building owner. This information shall include, but not be limited to, the information specified in Section E 503.6.3.1, Section E 503.6.3.2, and Section E 503.6.5.2. [ASHRAE 90.1:4.2.2.3]

  E 503.6.3.1 Required Information. Construction documents shall require that an operating manual and maintenance manual be provided to the building owner. The manuals shall include, at a minimum, the following:

  (1) Submittal data stating equipment rating and selected options for each piece of equipment requiring maintenance.

  (2) Operation manuals and maintenance manuals for each piece of equipment requiring maintenance. Required routine maintenance actions shall be clearly identified.

  (3) Names and addresses of not less than one qualified service agency.

  (4) A complete narrative of how each system is intended to operate.

  The Authority Having Jurisdiction shall only check to ensure that the construction documents require this information to be transmitted to the owner and should not expect copies of any of the materials.

  [ASHRAE 90.1:8.7.3.2]

  E 503.6.3.2 Lighting Manuals. Construction documents shall require for all lighting equipment and lighting controls that an operating manual and maintenance manual be provided to the building owner or the designated representative of the building owner within 90 days after the date of system acceptance. These manuals shall include, at a minimum, the following:

  (1) Submittal data indicating all selected options for each piece of lighting equipment, including but not limited to lamps, ballasts, drivers, and lighting controls.

  (2) Operation and maintenance manuals for each piece of lighting equipment and lighting controls with routine maintenance clearly identified including, as a minimum, a recommended relamping or cleaning program and a schedule for inspecting and recalibrating all lighting controls.

  (3) A complete narrative of how each lighting control system is intended to operate including recommended settings. [ASHRAE 90.1:9.7.3.2]

  E 503.6.4 Labeling of Material and Equipment. Materials and equipment shall be labeled in a manner that will allow for determination of their compliance with the applicable provisions of this appendix. [ASHRAE 90.1:4.2.3]

  E 503.6.5 Completion Requirements. Section E 503.6.5.1 through Section E 503.6.5.4 are mandatory provisions and are necessary to comply with this appendix.

• CMC § 503.1.2 Medium relevance — show source text

  E 503.1.2 Additions to Existing Buildings. Mechanical equipment and systems serving the heating, cooling, ventilating, or refrigeration needs of additions to existing buildings shall be in accordance with the requirements of this section as described in Section E 503.2.

  Exception: Where HVACR to an addition is provided by existing HVACR systems and equipment, such existing systems and equipment shall not be required to be in accordance with this appendix. A new system or equipment installed shall be in accordance with specific requirements applicable to those systems and equipment.

  [ASHRAE 90.1:6.1.1.2]

  E 503.1.3 Alterations to Heating, Ventilating, Air- Conditioning, and Refrigeration in Existing Buildings. New HVACR equipment as a direct replacement of existing HVACR equipment shall comply with the following sections as applicable for the equipment being replaced:

  (1) Section E 503.3 “Simplified Approach Option for HVAC Systems”

  (2) Section E 503.4 “Equipment Efficiencies, Verification, and Labeling Requirements”

  (3) Section E 503.4.6 “Zone Thermostatic Controls”

  (4) Section E 503.4.6.2 “Set-point Overlap Restrictions”

  (5) Section E 503.4.6.3 “Off-Hour Controls” except for Section E 503.4.6.3.4, “Zone Isolation”

  (6) Section E 503.4.6.4 “Ventilation System Controls”

  (7) Section E 503.4.6.8 “Freeze Protection and Snow/Ice Melting Systems”

  (8) Section E 503.4.6.9 “Ventilation Controls for HighOccupancy Areas” only for single-zone equipment

  (9) Section E 503.4.6.11 “Heated or Cooled Vestibules”

  (10)Section E 503.4.8 “Walk-In Coolers and Walk-In Freezers”

  (11)Section E 503.5.1 “Air Economizers” for units located outdoors

  (12)Section E 503.5.3 “Integrated Economizer Control”

  (13)Section E 503.5.4 “Economizer Heating System Impact”

  (14)Section E 503.5.6.1.2 “Fan Efficiency”

  (15)Section E 503.5.6.2 “Supply Fan Airflow Control”

  (16)Section E 503.5.6.5 “Fractional Horsepower (Kilowatt) Fan Motors”

  (17)Section E 503.5.7 “Boiler Turndown”

  (18)Section E 503.5.7.3 “Chiller and Boiler Isolation”

  (19)Section E 503.5.8.1 “Fan Speed Control.” [ASHRAE 90.1:6.1.1.3.1]

  E 503.1.3.1 New Cooling Systems. New cooling systems installed to serve previously uncooled spaces shall be in accordance with this section as described in Section E 503.2. [ASHRAE 90.1:6.1.1.3.2]

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  APPENDIX E

• CMC § 0.0296 Medium relevance — show source text

  Tubing shall comply with the requirements of Chapter 6 of the California Mechanical Code . 2. Tubing and connected devices shall be completely enclosed within a galvanized or paint-grade steel enclosure having a minimum thickness of 0.0296 inch (0.7534 mm) (No. 22 gage). Entry to the enclosure shall be by copper tubing with a protective grommet of neoprene or Teflon or by suitable brass compression to male barbed adapter. 3. Tubing shall be identified by appropriately documented coding. 4. Tubing shall be neatly tied and supported within the enclosure. Tubing bridging cabinets and doors or moveable devices shall be of sufficient length to avoid tension and excessive stress. Tubing shall be protected against abrasion. Tubing connected to devices on doors shall be fastened along hinges.

  [F] 909.13.2 Isolation from other functions. Control tubing serving other than smoke control functions shall be isolated by automatic isolation valves or shall be an independent system.

  [F] 909.13.3 Testing. Control air tubing shall be tested at three times the operating pressure for not less than 30 minutes without any noticeable loss in gauge pressure prior to final connection to devices.

  [F] 909.14 Marking and identification. The detection and control systems shall be clearly marked at all junctions, accesses and terminations.

  [F] 909.15 Control diagrams. Identical control diagrams showing all devices in the system and identifying their location and function shall be maintained current and kept on file with the fire code official, the fire department and in the fire command center in a format and manner approved by the fire code official.

  [F] 909.16 Firefighter’s smoke control panel. A firefighter’s smoke control panel for fire department emergency response purposes only shall be provided and shall include manual control or override of automatic control for mechanical smoke control systems. The panel shall be located in a fire command center complying with Section 911 in high-rise buildings Group I-2 occupancies having occu- pied floors located more than 75 feet above the lowest level of fire department vehicle access or buildings with smoke-protected assembly seating. In all other buildings, the firefighter’s smoke control panel shall be installed in an approved location adjacent to the fire alarm control panel. The firefighter’s smoke control panel shall comply with Sections 909.16.1 through 909.16.3.

  [F] 909.16.1 Smoke control systems. Fans within the building shall be shown on the firefighter’s control panel. A clear indication of the direction of airflow and the relationship of components shall be displayed. Status indicators shall be provided for all smoke control equipment, annunciated by fan and zone, and by approved pilot-lamp-type indicators as follows:

  1. Fans, dampers and other operating equipment in their normal status—WHITE.
  2. Fans, dampers and other operating equipment in their off or closed status—RED.
  3. Fans, dampers and other operating equipment in their on or open status—GREEN.
  4. Fans, dampers and other operating equipment in a fault status—YELLOW/AMBER.

  [F] 909.16.2 Smoke control panel. The firefighter’s control panel shall provide control capability over the complete smoke control system equipment within the building as follows:

  1. ON-AUTO-OFF control over each individual piece of operating smoke control equipment that can be controlled from other sources within the building.
• CMC § 1707.18.7 Medium relevance — show source text

  installation instructions.

  1707.18.7 Closed Cell Insulation. Buried horizontal open-loop system pipes passing parallel within 5 feet (1524 mm) of a wall, structure, or water pipe shall be insulated with R-2 minimum closed cell insulation.

  1707.18.8 Tracer Markings. Means shall be provided for underground detection or utility location of the buried pipe system. This shall include, but is not limited to, metallic detectable tape, with a thickness of not less than 11/64 of an inch (4.4 mm) and a width of 6 inches (152 mm).

  This warning marking shall be permanent, conspicuous and resistant to the environmental conditions and shall be placed within 1 foot to 2 feet (305 mm to 610 mm) on top of the horizontal piping of the heat exchanger installation.

  1708.0 System Start-Up. 1708.1 General. The following requirements shall be verified prior to system start-up:

  (1) Piping shall be cleaned, flushed, and purged.

  (2) The ground-heat exchanger and building piping shall be cleaned, flushed, and, where required, shall be filled with the heat transfer fluid medium. The ground loop system shall be tested at the design flow rate(s) and differential pressure(s) recorded. Where the actual pressure change at design flow is more than +/- 10 percent of the design flow pressure drop, the cause shall be identified and corrective action taken.

  (3) A method for the removal of air and a method for adding heat transfer fluid (where necessary) shall be provided.

  (4) The heat pumps shall be operational and adjustments shall be made in accordance with the manufacturer’s

  installation instructions.

  (5) All necessary additional flow tests of the ground-heat exchanger shall be completed prior to heat pump start-up.

  (6) Ground-heat exchanger and building piping, valves, and operating controls, shall be set, adjusted, and operating as required.

  (7) The system shall be labeled at the loop charging valves with a permanent-type label, indicating the type of heat transfer fluid used. Where antifreeze is used, the labels shall indicate the antifreeze type and concentration.

  (8) Supply and return lines, as well as associated isolation valves from individual boreholes or water wells, shall be identified and tagged.

  (9) Supply and return lines on submerged systems shall be identified in an approved manner, at the point of entry to a surface water resource.

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  1708.2 Operation and Maintenance Manual. An operation and maintenance manual for the geothermal system shall be provided to the owner. The manual shall include information on required testing and maintenance of the system. Training shall be provided on the system’s operation, maintenance requirements, and on the content of the operation and maintenance manual. The operation and maintenance manual shall contain a layout of the ground-heat exchanger and building loop.

  1708.3 Labeling and Marking. Ground source heat pump ground-loop system piping shall be marked with tape, metal tags, or other methods where it enters a building. The marking shall indicate the following words: “GROUND SOURCE HEAT PUMP-LOOP SYSTEM.” The marking shall indicate antifreeze used in the system by name and concentration.

  1708.4 Documentation. The ground source heat pump system as-built installation drawings and instructions shall be provided to the building owner or designated agent.

• CMC § 303.7 Medium relevance — show source text

  303.7 Liquefied Petroleum Gas (LP-Gas) Facilities . . . . . . . . . . . . . . 53

  303.8 Appliances on Roofs. . . . . . . . . . . . 53

  303.9 Avoiding Strain on Gas Piping . . . . 53

  303.10 Clearance to Combustible

  Materials . . . . . . . . . . . . . . . . . . . . . 53

  303.11 Installation in Commercial

  Garages . . . . . . . . . . . . . . . . . . . . . 54

  303.12 Installation in Aircraft Hangars . . . . 54

  304.0 Accessibility for Service . . . . . . . . . 54

  304.1 General. . . . . . . . . . . . . . . . . . . . . . 54

  304.2 Sloped Roof . . . . . . . . . . . . . . . . . . 54

  304.3 Access to Appliances on Roofs . . . 54

  304.4 Appliances in Attics and Under-Floor Spaces . . . . . . . . . . . . 54

  305.0 Location . . . . . . . . . . . . . . . . . . . . . 55

  305.1 Installation in Residential Garages . . 55

  305.2 Pit Location. . . . . . . . . . . . . . . . . . . 55

  305.3 Flood Hazard Areas . . . . . . . . . . . . 55

  305.4 Elevator Shaft . . . . . . . . . . . . . . . . . 55

  305.5 Drainage Pan . . . . . . . . . . . . . . . . . 55

  305.6 Outdoor Locations . . . . . . . . . . . . . 55

  306.0 Automatic Control Devices . . . . . . . 55

  306.1 General. . . . . . . . . . . . . . . . . . . . . . 55

  306.2 Building Automation Systems . . . . 56

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  TABLE OF CONTENTS

  307.0 Labeling . . . . . . . . . . . . . . . . . . . . . 56

  307.1 Fuel-Burning Appliances . . . . . . . . 56

  307.2 Electric Heating Appliances . . . . . . 56

  307.3 Heat Pump and Electric Cooling Appliances . . . . . . . . . . . . . . . . . . . 56

  307.4 Absorption Units . . . . . . . . . . . . . . . 56

  308.0 Improper Location. . . . . . . . . . . . . . 57

  308.1 General. . . . . . . . . . . . . . . . . . . . . . 57

  309.0 Workmanship . . . . . . . . . . . . . . . . . 57

  309.1 Engineering Practices. . . . . . . . . . . 57

  309.2 Concealing Imperfections . . . . . . . . 57

  309.3 Installation Practices. . . . . . . . . . . . 57

• CMC § 90.1 Medium relevance — show source text

  [ASHRAE 90.1:6.4.3.7] E 502.10.5 Other Controls. Where setback, zoned, humidity and cooling controls and equipment are provided, they shall be designed and installed in accordance with Section E 502.10 through Section E 502.10.3.1.

  [ASHRAE 90.2-2007:6.10.3.3]

  E 502.11 Whole House Fans. Whole house exhaust fans

  shall have insulated louvers or covers which close where the

  fan is off. Covers or louvers shall have an insulation value of not less than R-4.2, and shall be installed in accordance with the manufacturer’s installation instructions. The attic openings shall be sufficient to accommodate the ventilation capacity of the whole house fan. The operation of the whole house fan shall be considered in determining the adequacy of providing combustion air in accordance with this code. E 502.12 Dampers. Dampers shall be installed to close off outdoor air inlets and exhaust outlets where the ventilation system is not operating.

  E 503.0 Heating, Ventilation, and Air-Conditioning – Other than Low-Rise Residential Buildings. E 503.1 General. The heating, ventilation, and air-conditioning in buildings, other than single-family houses, multi-family structures of not more than three stories above grade, and modular houses, shall be in accordance with Section E 503.0.

  E 503.1.1 New Buildings. Mechanical equipment and systems serving the heating, cooling, ventilating, or refrigeration needs of new buildings shall comply with the requirements of this section as described in Section E 503.2. [ASHRAE 90.1:6.1.1.1]

  E 503.1.2 Additions to Existing Buildings. Mechanical equipment and systems serving the heating, cooling, ventilating, or refrigeration needs of additions to existing buildings shall be in accordance with the requirements of this section as described in Section E 503.2.

  Exception: Where HVACR to an addition is provided by existing HVACR systems and equipment, such existing systems and equipment shall not be required to be in accordance with this appendix. A new system or equipment installed shall be in accordance with specific requirements applicable to those systems and equipment.

  [ASHRAE 90.1:6.1.1.2]

  E 503.1.3 Alterations to Heating, Ventilating, Air- Conditioning, and Refrigeration in Existing Buildings. New HVACR equipment as a direct replacement of existing HVACR equipment shall comply with the following sections as applicable for the equipment being replaced:

  (1) Section E 503.3 “Simplified Approach Option for HVAC Systems”

  (2) Section E 503.4 “Equipment Efficiencies, Verification, and Labeling Requirements”

  (3) Section E 503.4.6 “Zone Thermostatic Controls”

  (4) Section E 503.4.6.2 “Set-point Overlap Restrictions”

  (5) Section E 503.4.6.3 “Off-Hour Controls” except for Section E 503.4.6.3.4, “Zone Isolation”

  (6) Section E 503.4.6.4 “Ventilation System Controls”

  (7) Section E 503.4.6.8 “Freeze Protection and Snow/Ice Melting Systems”

• CMC § 1112.13 Medium relevance — show source text

  1112.13 Rating of Pressure-Relief Device. . . . . . . . . . . . . . . . . . . . . . 244

  1112.14 Rating of Rupture Members and Fusible Plugs . . . . . . . . . . . . . . . . 244

  1113.0 Overpressure Protection. . . . . . . . 244

  1113.1 General. . . . . . . . . . . . . . . . . . . . . 244

  1113.2 Type of Protection . . . . . . . . . . . . 245

  1113.3 Discharging into Lowside of System . . . . . . . . . . . . . . . . . . . . . 245

  1113.4 Parallel Pressure-Relief Devices . . 245

  1113.5 Discharge Capacity . . . . . . . . . . . 245

  1113.6 Three-Way Valve . . . . . . . . . . . . . 245

  1114.0 Special Discharge Requirements. . 245

  1114.1 General. . . . . . . . . . . . . . . . . . . . . 245

  1114.2 Design Requirements . . . . . . . . . . 245

  1114.3 Testing . . . . . . . . . . . . . . . . . . . . . 245

  1115.0 Labeling and Identification . . . . . . 245

  1115.1 General. . . . . . . . . . . . . . . . . . . . . 245

  1115.2 Volume and Type . . . . . . . . . . . . . 245

  1115.3 Permanent Sign . . . . . . . . . . . . . . 245

  1115.4 Marking of Pressure-Relief Devices. . . . . . . . . . . . . . . . . . . . . 245

  1115.5 Nameplate . . . . . . . . . . . . . . . . . . 245

  1116.0 Testing of Refrigeration Equipment . . . . . . . . . . . . . . . . . . 246

  1116.1 Factory Tests . . . . . . . . . . . . . . . . 246

  1116.2 Field Tests . . . . . . . . . . . . . . . . . . 246

  1116.3 Test Gases . . . . . . . . . . . . . . . . . . 246

  1116.4 Declaration . . . . . . . . . . . . . . . . . . 246

  1116.5 Brine Systems . . . . . . . . . . . . . . . 247

  1117.0 Refrigerant-Containing Pressure Vessels . . . . . . . . . . . . . . . . . . . . . 247

  1117.1 Inside Dimensions 6 Inches

  or Less . . . . . . . . . . . . . . . . . . . . . 247

  1117.2 Inside Dimensions More than

  6 Inches . . . . . . . . . . . . . . . . . . . . 247

  1117.3 Pressure Vessels for 15 psig or Less . . . . . . . . . . . . . . . . . . . . . 247

• CMC § 7.6 Medium relevance — show source text

  [ASHRAE 15:7.6]

  1104.6.1 Refrigerant Concentration Limits. Occupied spaces shall comply with the releasable charge limitations of the equipment listing and ASHRAE 15. Unoccupied spaces with refrigerant containing equipment, not including continuous piping or tubing, shall comply with the releasable charge limitations of the equipment listing or Section 1104.6.4. {ASHRAE 15:7.6.1-7.6.1.2}

  1104.6.2 Listing and Installation Requirements. Refrigeration systems shall be listed and shall be installed in accordance with listing, the manufacturer’s instructions, and any markings on the equipment restricting the installation. [ASHRAE 15:7.6.2]

  1104.6.2.1 Nameplate. The nameplate required by Section 1115.5 shall include a symbol indicating that a flammable refrigerant is used, as specified by the product listing. [ASHRAE 15:7.6.2.1]

  1104.6.2.2 Labeling. A label indicating a flammable refrigerant is used shall be placed adjacent to service ports and other locations where service involving components containing refrigerant is performed, as specified by the product listing.

  [ASHRAE 15:7.6.2.2]

  1104.6.2.3 Refrigerant Detection Systems. Refrigerant detection systems shall be in accordance with the listing and ASHRAE 15.

  2025 CALIFORNIA MECHANICAL CODE 229

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

  REFRIGERATION

  1104.6.2.4 Refrigerant Concentration Above Limit. When the refrigerant detection system senses a refrigerant exceeding its setpoint, the following actions shall be taken:

  (1) The supply air fan of the equipment shall activate with a minimum airflow rate specified by the manufacturer.

  (2) Turn off the compressor and all other electrical devices, excluding the control power transformers, control systems, and the supply air fan. The supply air fan shall continue to operate for at least five minutes after the refrigerant detection system has sensed a drop in the refrigerant concentration below the value specified in Section 1104.6.6(b).

  Exception: The compressor operation shall not be turned off when the compressor operation reduces the leak rate or the total amount of

  released refrigerant to the indoor space.

  (3) Any device that controls airflow located within the product or in ductwork that supplies air to the occupied space shall be fully open. Any device that controls airflow shall be listed.