ASHRAE-90.1-2022- - Page 074

Extracted Content

o. 6.5.3.2.1, “Supply Fan Airflow Control” p. 6.5.3.6, “Fractional Horsepower Fan Motors” q. 6.5.4.1, “Boiler Turndown” r. 6.5.4.3, “Chiller and Boiler Isolation” s. 6.5.5.2, “Fan Speed Control”

6.1.4.2 New cooling systems installed to serve previously uncooled spaces shall comply with this section as described in Section 6.2.

6.1.4.3 Alterations to existing cooling systems shall not decrease economizer capability unless the sys- tem complies with Section 6.5.1.

6.1.4.4 New and replacement ductwork shall comply with Sections 6.4.4.1 and 6.4.4.2. 6.1.4.5 New and replacement piping shall comply with Section 6.4.4.1. Exceptions to 6.1.4.5: Compliance shall not be required

1. for equipment that is being modified or repaired but not replaced, provided that such modifications and/or repairs will not result in an increase in the annual energy consumption of the equip- ment using the same energy type;
2. where a replacement or alteration of equipment requires extensive revisions to other systems, equipment, or elements of a building, and such replaced or altered equipment is a like-for-like replacement;
3. for a refrigerant change of existing equipment ;
4. for the relocation of existing equipment ; or
5. for ducts and piping where there is insufficient space or access to meet these requirements.

6.1.5 Climate. Climate zones shall be determined in accordance with Section 5.1.5.

6.2 Compliance Paths. Mechanical equipment and systems providing heating, cooling, ventilating, or refrigeration shall comply with Sections 6.2.1 and 6.2.2.

6.2.1 Requirements for all Compliance Paths. Mechanical equipment and systems shall comply with all of the following:

a. Section 6.1, “General” b. Section 6.4, “Mandatory Provisions”

Exception to 6.2.1(b): When compliance is shown using Section 6.2.2(a), compliance with Section 6.4

is not required unless required in Section 6.3.2. c. Section 6.7, “Submittals” d. Section 6.8, “Minimum Equipment Efficiency Tables”

6.2.2 Additional Requirements to Comply with Section 6. Refrigeration equipment and systems shall comply with Section 6.5, “Prescriptive Compliance Path.” All building HVAC systems shall comply with one of the following:

a. Section 6.3, “Simplified Approach Building Compliance Path for HVAC Systems” b. Section 6.5, “Prescriptive Compliance Path” c. Section 6.6.1, “Computer Room System Path” d. Section 6.6.2, “Mechanical System Performance Path”

Informative Note: Section 6.3 requires all HVAC systems in the building to qualify for the simplified path. Section 6.6.2 requires all allowable systems to meet Normative Appendix L requirements. Section 6.6.2 does allow part of the building to use the Mechanical System Performance Path and part of the building to use Section 6.5 where there are excluded occupancy types or system types in Section L1.1.1.2. HVAC sys- tems for larger computer rooms may comply with either Section 6.5, Section 6.6.1, or Section 6.6.2.

6.3 Simplified Approach Building Compliance Path for HVAC Systems 6.3.1 Scope. The simplified approach is an optional path for compliance when the following conditions are met:

a. The building is two stories or fewer in height. b. Gross floor area is less than 25,000 ft [2] . c. Each HVAC system in the building complies with the requirements listed in Section 6.3.2.

6.3.2 Criteria. The HVAC system must meet all of the following criteria:

a. The system serves a single HVAC zone . b. The equipment must meet the variable flow requirements of Section 6.5.3.2.1.

72 ANSI/ASHRAE/IES Standard 90.1-2022 (I-P)