ASHRAE-90.1-2022- - Page 375
Extracted Content
| Table L.1.1.1 Method | Proposed Building HVAC Systems Allowed to Use the Mechanical System Performance Rating |
|---|---|
| System No. | System Name |
| 1 | Packaged terminal air conditioner(with electric or hydronic heat) |
| 2 | Packaged terminal heat pump |
| 3 | Packaged single-zone furnacea and/or air-cooled air conditioner (includes split systems b) |
| 4 | Packaged single-zone heat pump (air-to-air only) (includes split systems b and electric or gas supplemental heat) |
| 5 | VRF system (air source) |
| 6 | Four-pipe fan coil |
| 7 | Water-source heat pump (water loop), water-source_VRF system_, or water-source air conditioner |
| 8 | Ground-source heat pump |
| 9 | Packaged_VAV system_ (DX cooling) a |
| 10 | VAV system (hydronic cooling) a |
| 11 | VAV system with fan-powered_terminal_ units |
| 12 | DOAS (in conjunction with_systems_ 1 through 8) |
a. Reheat or primary heat may be electric, hydronic, or gas furnace. b. Condensing units with DX air handlers are modeled as package furnace with air conditioners or heat pumps. Informative Note: See Section 3.3 for a full list of terms used in this table.
c. HVAC systems serving portions of the building that are also served in parallel by other HVAC systems not
allowed to use the Mechanical System Performance Rating Method d. HVAC systems using any of the following:
- District heating or cooling
- Small-duct high-velocity air-cooled, space -constrained air-cooled, single-package vertical air condi- tioner, single-package vertical heat pump
- Double-duct air conditioner or double-duct heat pump as defined in 10CFR part 431, Subpart F
- Packaged terminal air conditioners and packaged terminal heat pumps that have cooling capacity greater than 12,000 Btu/h
- Systems with a common heating source serving both HVAC and service water heating equipment
- HVAC systems that provide recovered heat for service water heating
Exceptions to L1.1.1.2(a) and (c):
- Multiple-zone HVAC systems in Table L.1.1.1, including dedicated outdoor air systems (DOAS), where 80% or more of system supply air serves allowed building use types in accordance with Section L1.1.1.1 and 20% or less of system supply air serves excluded areas in Items (a) or (c).
- Central chiller or boiler plants where 80% or more of capacity serves allowed building use types in accordance with Section L1.1.1.1 and 20% or less of capacity serves excluded areas in items (a) or (c).
L2. MECHANICAL SYSTEM PERFORMANCE RATING METHOD
L2.1 Compliance
L2.1.1 Mandatory Requirements. All HVAC systems in the proposed building design shall comply with the requirements in Section 6.2.1.
Informative Note: Buildings using the Mechanical System Performance Rating Method are required to meet all mandatory provisions in Section 6.4 in accordance with Section 6.2.1. For example, while demand control ventilation ( DCV ) controlled area in the proposed building is one of the user entries in the simulation program, the minimum entry needs to meet the floor area where DCV is required in accordance with Section 6.4.3.8. The intent of this entry is to give credit for DCV control in more area than required, but not to allow DCV that is a mandatory requirement to be traded off with other efficiency improvements.
ANSI/ASHRAE/IES Standard 90.1-2022 (I-P) 373