ASHRAE-90.1-2022- - Page 189
Extracted Content
| Table 11.5.2.2.5 GSHP Heat | Rejection Adjustments | Col3 | Col4 |
|---|---|---|---|
| Climate Zones | HR****adj by Field Source Capacity | HR****adj by Field Source Capacity | HR****adj by Field Source Capacity |
| Climate Zones | Full-Sized Bore Field with no Heat Rejection | 90% Hours Source Size; Dry-Cooler Heat Rejection | 90% Hours Source Size; Evaporative Heat Rejection |
| 0A, 1B, 2B, 3A, 3B, 4A, 4B | 3.3 | 2.6 | |
| 0B, 1A, 2A, 3C | 7.6 | 5.3 | |
| 4C, 5A, 5B, 5C | 2.3 | 1.5 | |
| 6A, 6B, 7, 8 | 1.4 | 1.1 | |
| All climate zones | 1.0 |
For data centers using Standard 90.4, EI cool shall be calculated as follows:
EI cool
= AMLC----------------------- max - - 1 AMLC des
where AMLC max = maximum annualized mechanical load component from Standard 90.4, Table 6.5 AMLC des = as-designed annualized mechanical load component calculated in accordance with Standard 90.4, Section 6.5 Informative Note: An example of an annualized or part-load cooling efficiency is IEER rather than EER, or IPLV kW /ton rather than FL kW /ton. Where only one efficiency rating is provided for equipment in Section 6.8.1 or Informative Appendix F, use that metric.
11.5.2.2.4 H04: Residential Space HVAC Control. To achieve this credit, in buildings with nontran- sient residential spaces, HVAC system s serving dwelling units shall be controlled to automatically activate the setback condition with one of the following:
a. A main control by each dwelling-unit main entrance that initiates setback and non- ventilation mode for all
HVAC units serving the dwelling unit and that is clearly identified as “Heating/Cooling Master Setback.” b. Occupancy sensors in each room of the dwelling unit combined with a door switch to initiate setback and
non- ventilation mode for all HVAC units in the dwelling within 20 minutes of a door switch operation followed by all spaces being vacant. Where separate room HVAC units are used, individual occupancy sensors shall meet this requirement. c. An advanced learning thermostat or controller that recognizes occupant presence and automatically cre ates a schedule for occupancy and provides a dynamic setback schedule based on when the spaces are generally unoccupied. Where ventilation is provided by a separate system, it shall also have occupancy sensor control .
11.5.2.2.5 H05: Ground-Source Heat-Pump System. To achieve this credit, a ground-source heatpump system shall provide cooling and heating for at least 25% of the gross conditioned building area . The ground-source heat-pump systems shall include building ground-loop HVAC systems coupled with a closedbore ground-heat exchanger, submerged heat exchanger using water-based fluid as a heat transfer medium, groundwater (well), or fluid infrastructure (such as effluent and wastewater), and shall comply with the following:
a. Loop pump(s) shall have controls and/or devices that will result in pump motor demand of no more than
30% of design wattage at 50% of design water flow and allow turndown to 15% flow. Alternatively, a separate field-loop pump shall be provided, with either a variable-speed building pump or individual pumps for each ground-source heat pump. b. The geothermal-source exchanger shall be sized based on the heating and cooling loads served by the
ground-source heat-pump system and shall comply with one of the following:
- A closed bore field shall have at least 400 lineal ft of bore piping per 12,000 Btu/h of system cooling or heating capacity, whichever is greater. The system shall not include additional heat rejection or addition devices.
- The ground source shall be sized such that the loop heat pumps provide 100% of the heating and cooling loads for at least 90% of both the cooling and heating system annual operating hours without requiring any supplemental heating or heat rejection from nonground sources, as demonstrated by an
ANSI/ASHRAE/IES Standard 90.1-2022 (I-P) 187