Washington Administrative Code › Title 51 - Enterprise Services, Department of (Building Code Council) › Chapter 51-11C - State Building Code adoption and amendment of the 2021 edition of the International Energy Conservation Code, Commercial › Section 51-11C-40349 - Sections C403.4.11 and C403.4.12

Current through Register Vol. 24-14, July 15, 2024
C403.4.11
Direct
			 digital control systems.
Direct digital control (DDC) shall be required
			 as specified in Sections C403.4.11.1 through C403.4.11.4.
C403.4.11.1
DDC applications.
DDC shall be provided in the applications and qualifications listed in Table
			 C403.4.11.1 and for load management measures where installed to meet the
			 requirements of Section C406.3.
C403.4.11.2
DDC controls.
Where
			 DDC is required by Section C403.4.11.1, the DDC system shall be configured to
			 perform all of the following functions, as required to provide the system and
			 zone control logic required in Sections C403.2, C403.5, C403.6.8 and C403.4.3:
1. Monitor zone and system demand for fan
			 pressure, pump pressure, heating and cooling.
2. Transfer zone and system demand
			 information from zones to air distribution system controllers and from air
			 distribution systems to heating and cooling plant controllers.
C403.4.11.3
DDC
			 display.
Where DDC is required by Section C403.4.11.1 for new buildings,
			 the DDC system shall be configured to gather and provide trending data and
			 graphically displaying input and output points.
C403.4.11.4
DDC demand response
			 setpoint adjustment.
Where DDC is required by Section C403.4.11.1 for
			 new buildings and serve mechanical systems with a cooling capacity exceeding
			 780,000 Btu/h (2,662 kW), the
DDC system
shall be capable of
			 demand response setpoint adjustment. The
DDC system
shall be
			 configured with control logic to increase the cooling zone setpoints by at
			 least 2°F (1°C) and reduce the heating zone setpoints by at least
			 2°F (1°C) when activated by a
demand response signal
.
			 The
demand response signal
shall be a binary input to the
			 control system or other interface approved by the serving electric utility.
Table C403.4.11.1
DDC Applications and Qualifications
Building Status
Application
Qualifications
New building
Air-handling system and all zones served by the
						  system
Individual systems supplying more than three zones and
						  with fan system bhp of 10 hp and larger
Chilled-water plant and all coils and terminal units
						  served by the system
Individual plants supplying more than three zones and
						  with design cooling capacity of 300,000 Btu/h and larger
Hot-water plant and all coils and terminal units served
						  by the system
Individual plants supplying more than three zones and
						  with design heating capacity of 300,000 Btu/h and larger
Alteration or addition
Zone terminal unit such as VAV box
Where existing zones served by the same air-handling,
						  chilled-water, or hot-water system have DDC
Air-handling system or fan coil
Where existing air-handling system(s) and fan coil(s)
						  served by the same chilled- or hot-water plant have DDC
New air-handling system and all new zones served by the
						  system
Individual systems with fan system bhp of 10 hp and
						  larger and supplying more than three zones and more than 75 percent of zones
						  are new
New or upgraded chilled-water plant
Where all chillers are new and plant design cooling
						  capacity is 300,000 Btu/h and larger
New or upgraded hot-water plant
Where all boilers are new and plant design heating
						  capacity is 300,000 Btu/h and larger