A5.207.5 Controls for Space-Conditioning Systems
The supply of heating and cooling energy to each space-conditioning zone or dwelling unit shall be controlled by an individual thermostatic control that responds to temperature within the zone and that meets the applicable requirements of Section A22.214.171.124.
Exception: An independent perimeter heating or cooling system may serve more than one zone without individual thermostatic controls if:
- All zones are also served by an interior cooling system;
- The perimeter system is designed solely to offset envelope heat losses or gains;
- The perimeter system has at least one thermostatic control for each building orientation of 50 feet or more; and
- The perimeter system is controlled by at least one thermostat located in one of the zones served by the system.
The individual thermostatic controls required by Section A126.96.36.199 shall meet the following requirements as applicable:
- Where used to control comfort heating, the thermostatic controls shall be capable of being set, locally or remotely, down to 55°F or lower.
- Where used to control comfort cooling, the thermostatic controls shall be capable of being set, locally or remotely, up to 85°F or higher.
Outdoor air supply and exhaust equipment shall be installed with dampers that automatically close upon fan shutdown.
- Where it can be demonstrated to the satisfaction of the enforcing agency that the equipment serves an area that must operate continuously.
- Gravity and other nonelectrical equipment that has readily accessible manual damper controls.
- At combustion air intakes and shaft vents.
- Where prohibited by other provisions of law.
HVAC systems with DDC to the Zone level shall be programmed to allow centralized demand shed for noncritical zones as follows:
- The controls shall have a capability to remotely setup the operating cooling temperature set points by 4 degrees or more in all noncritical zones on signal from a centralized contact or software point within an Energy Management Control System (EMCS).
- The controls shall remotely set down the operating heating temperature set points by 4 degrees or more in all noncritical zones on signal from a centralized contact or software point within an EMCS.
- The controls shall have capabilities to remotely reset the temperatures in all noncritical zones to original operating levels on signal from a centralized contact or software point within an EMCS.
- The controls shall be programmed to provide an adjustable rate of change for the temperature setup and reset.