19. Provide temperature controls for all multi-occupant spaces, such as conference rooms. Provide automatic ventilation and temperature setback based on positive and automatic detection of vacancy. This can be accomplished through a communication link to the lighting control system or a dedicated occupancy sensor. When vacancy is detected, the VAV minimum flow for the zone shall temporarily reset to 0 cfm and the setpoint deadband shall increase by 2 °F. Upon detection of vacancy, the heating setpoint shall decrease by 1 °F and the cooling setpoint shall increase by 1 °F. When occupancy resumes, the reverse shall occur. 20. Ensure HVAC design specifications include operational set points and schedule to meet the most recent version of ASHRAE 55 requirements. Controls contractor to ensure set points are programmed; Commissioning Authority to verify. 21. Install BTU meters at the tenant point of connection to base building chilled water, heating hot water, and condenser water systems. Alternatively, they can be installed in each MER or AHU to capture all Tenant usage. 22. Provide return water temperature sensors for all chilled water, hot water, and condenser water equipment over 5 tons. Provide controls on water cooled DX systems which maintain a minimum 10F condenser/chilled water temperature rise during DX cooling operation and zero flowrate when the compressors are not operating. The DX free cooling coil and FCU cooling coils shall be selected for chilled water temperatures of 45/55 Degrees. 23. Documents shall specify that all duct probes and control raceway penetrating ductwork or air handler casing including internal partitions in air handlers shall be externally AND internally sealed airtight. Holes in walls behind all wall mounted control devices regardless of where they are mounted or what parameter they are sensing shall be sealed airtight. 24. The pressure drop through all chilled water coils (e.g., CRAC free cooling coils, AHUs, FCU, condensers) and associated piping and accessory shall not exceed building standards. Chilled water coils and other loads connected to the chilled water system shall not exceed a pressure drop of 5 ft of water. Provide means of measuring and balancing the chilled water, hot water and condenser water to all equipment. All control valves shall be pressure independent type or have balancing valves with calibrated orifices and memory stops. Where pressure independent valves are used, a calibrated orifice is still required for flow measurement and verification. Electronic pressure independent control valves are acceptable for this purpose. Quarter turn balancing valves are not acceptable. Automatic flow limiting valves are not acceptable. If equipment is not available that meets available systems pressures, the designer shall include a variable speed booster pump in series with the modulating control valve serving the equipment. 25. Three way valves are not permitted on any chilled water, hot water, dual water temperature, or condenser water loads. Any three way valves on existing equipment planned to remain as part of the project shall be replaced with two-way valves. All flow control shall be modulating with two way valves. Water blending systems for chilled beams, radiant cooling, and condenser water loads connected to a chilled water system shall use two way valves to control delivery of chilled water supply together with a local circulator pump. The Cv of valves supplying such blending systems shall be properly selected. Such systems may also incorporate a three-way valve or local injection pump to make use of chilled water returning from AHU coils within the project boundary and outboard of valved connections to chilled water mains, but such piping must be configured with check valves as required to prevent chilled water supply water from being connected directly to chilled water return lines.
Made with FlippingBook - Online Brochure Maker