// CODE SNIPPET
G184.108.40.206 System Fan Power
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System fan electrical power for supply, return, exhaust, and relief (excluding power to fan-powered VAV boxes) shall be calculated using the following formulas:
For Systems 1 and 2,
Pfan = CFMs × 0.3
For Systems 3 through 8, and 11, 12, and 13,
Pfan = bhp × 746/fan motor efficiency
For Systems 9 and 10 (supply fan),
Pfan = CFMs × 0.3
Pfan = CFMnmc × 0.054
|Pfan||=||electric power to fan motor, W|
|bhp||=||brake horsepower of baseline fan motor from Table G220.127.116.11|
|fan motor efficiency||=||the efficiency from Table G3.9.1 for the next motor size greater than the bhp|
|CFMs||=||the baseline system maximum design supply fan airflow rate, cfm|
|CFMnmc||=||the baseline non-mechanical cooling fan airflow, cfm|
|Baseline Fan Motor Brake Horsepower|
|Constant-Volume Systems 3, 4, 12, and 13||Variable-Volume Systems 5 to 8||Variable-Volume System 11|
|CFMs × 0.00094 + A||CFMs × 0.0013 + A||CFMs × 0.00062 + A|
- Where A is calculated according to Section 18.104.22.168.1 using the pressure-drop adjustment from the proposed design and the design flow rate of the baseline building system.
- Do not include pressure-drop adjustments for evaporative coolers or heat recovery devices that are not required in the baseline building system by Section G22.214.171.124.
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2021 Oregon Energy Efficiency Specialty Code (OEESC) > Normative Appendix G Performance Rating Method > G3 Calculation of the Proposed Design and Baseline Building Performance > G3.1 Building Performance Calculations > G3.1.3 System-Specific Baseline HVAC System Requirements > G22.214.171.124 Fan Power and Control (Systems 6 and 8)