C403.3.2 HVAC equipment performance requirements. Equipment shall meet the minimum efficiency requirements of Tables C403.3.2(1) through C403.3.2(12) when tested and rated in accordance with the applicable test procedure. Plate-type liquid-to-liquid heat exchangers shall meet the minimum requirements of Table C403.3.2(10). The efficiency shall be verified through certification and listed under an approved certification program or, if no certification program exists, the equipment efficiency ratings shall be supported by data furnished by the manufacturer. Where multiple rating conditions or performance requirements are provided, the equipment shall satisfy all stated requirements. Where components, such as indoor or outdoor coils, from different manufacturers are used, calculations and supporting data shall be furnished by the designer that demonstrates that the combined efficiency of the specified components meets the requirements herein.
Gas-fired and oil-fired forced air furnaces with input ratings ≥ 225,000 Btu/h (65 kW) and all unit heaters shall also have an intermittent ignition or interrupted device (IID), and have either mechanical draft (including power venting) or a flue damper. A vent damper is an acceptable alternative to a flue damper for furnaces where combustion air is drawn from the conditioned space. All furnaces with input ratings ≥ 225,000 Btu/h (65 kW), including electric furnaces, that are not located within the conditioned space shall have jacket losses not exceeding 0.75 percent of the input rating.
C403.3.2.1 Chillers. Chilled water plants and buildings with more than 500 tons total capacity shall not have more than 100 tons provided by air-cooled chillers.
EXCEPTIONS: | 1. Where the designer demonstrates that the water quality at the building site fails to meet manufacturer's specifications for the use of water-cooled equipment. |
| 2. Air-cooled chillers with minimum efficiencies at least 10 percent higher than those listed in Table C403.3.2(7). |
| 3. Replacement of existing air-cooled chiller equipment. |
| 4. Air-to-water heat pump units that are configured to provide both heating and cooling and that are rated in accordance with AHRI 550/590. Where the air-to-water heat pumps are designed for a maximum supply leaving water temperature of less than 140°F, the efficiency rating will be calculated and reported at the maximum unit leaving water temperature for this test condition. |
C403.3.2.2 Water-cooled centrifugal chilling package. Equipment not designed for operation at AHRI Standard 550/590 test conditions of 44°F (7°C) leaving chilled-water temperature and 2.4 gpm/ton evaporator fluid flow and 85°F (29°C) entering condenser water temperature with 3 gpm/ton (0.054 L/s • kW) condenser water flow shall have maximum full-load kW/ton (FL) and part-load ratings adjusted using Equations 4-7 and 4-8.
(Equation 4-7)
(Equation 4-8)
Where: | |
Kadj | = | A × B |
FL | = | Full-load kW/ton values as specified in Table C403.3.2(7) |
FLadj | = | Maximum full-load kW/ton rating, adjusted for nonstandard conditions |
IPLV | = | Value as specified in Table C403.3.2(7) |
PLVadj | = | Maximum NPLV rating, adjusted for nonstandard conditions |
A | = | 0.00000014592 × (LIFT)4 - 0.0000346496 × (LIFT)3 + 0.00314196 × (LIFT)2 - 0.147199 × LIFT + 3.9302 |
B | = | 0.0015 × LvgEvap (° F) + 0.934 |
LIFT | = | LvgCond - LvgEvap |
LvgCond | = | Full-load condenser leaving fluid temperature (°F) |
LvgEvap | = | Full-load evaporator leaving temperature (°F) |
The FLadj and PLVadj values are only applicable for centrifugal chillers meeting all of the following full-load design ranges:
1. Minimum evaporator leaving temperature: 36°F.
2. Maximum condenser leaving temperature: 115°F.
3. LIFT is not less than 20°F (11.1°C) and not greater than 80°F (44.4°C).
C403.3.2.3 Positive displacement (air- and water-cooled) chilling packages. Equipment with a leaving fluid temperature higher than 32°F (0°C) and water-cooled positive displacement chilling packages with a condenser leaving fluid temperature below 115°F (46°C) shall meet the requirements of Table C403.3.2(7) when tested or certified with water at standard rating conditions, in accordance with the referenced test procedure.
C403.3.2.4 Packaged electric heating and cooling equipment. Packaged electric equipment providing both heating and cooling with a total cooling capacity greater than 6,000 Btu/h shall be a heat pump.
EXCEPTION: | Unstaffed equipment shelters or cabinets used solely for personal wireless service facilities. |
C403.3.2.5 Humidification. If an air economizer is required on a cooling system for which humidification equipment is to be provided to maintain minimum indoor humidity levels, then the humidifier shall be of the adiabatic type (direct evaporative media or fog atomization type).
EXCEPTIONS: | 1. Health care facilities licensed by the state where chapter 246-320 or 246-330 WAC requires steam injection humidifiers in duct work downstream of final filters. |
| 2. Systems with water economizer. |
| 3. 100 percent outside air systems with no provisions for air recirculation to the central supply fan. |
| 4. Nonadiabatic humidifiers cumulatively serving no more than 10 percent of a building's air economizer capacity as measured in cfm. This refers to the system cfm serving rooms with stand alone or duct mounted humidifiers. |
[Statutory Authority: RCW
19.27A.020,
19.27A.025,
19.27A.160 and chapter
19.27 RCW. WSR 19-24-040, § 51-11C-40332, filed 11/26/19, effective 7/1/20. Statutory Authority: RCW
19.27A.025,
19.27A.160, and
19.27.074. WSR 16-03-072, § 51-11C-40332, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW
19.27A.025,
19.27A.045, and
19.27.074. WSR 13-20-120, § 51-11C-40332, filed 10/1/13, effective 11/1/13. Statutory Authority: RCW
19.27A.020,
19.27A.025 and chapters
19.27 and
34.05 RCW. WSR 13-04-056, § 51-11C-40332, filed 2/1/13, effective 7/1/13.]