11 SOW Requirements for Hines AC Shop.pdf

SOW requirements for A/C Shop

10/31/2022

New Building Automation Controls and Integration to BAS Supervisor

• The current BAS (Building Automation System) utilizes Johnson Controls Facility Explorer with BACnet communication.

o Any new controls are required: FX platform by Johnson Controls utilizing BACnet communication. SSJ provided in separate document.

o METASYS and N2 communication shall not be used on any project at Edward Hines

Jr. VAMC or any of the Community Based Outpatient Clinics.

• If project spans multiple floors with new controls, a new JACE shall be used for each floor where controls are being installed.

o If a floor has a JACE in use, a new JACE shall be provided by installing contractor to include enough points to incorporate any new controls as well as existing controls.

o Any new JACE provided shall have Wi-Fi capability.

o JACE IP address shall be requested from AC Shop Supervisor

▪ On-site controls contractor maintains list of available IP addresses

• To prevent duplicate device instance IDs, device instance ID’s must be requested from AC

Shop Supervisor.

o Device instance IDs are given out in blocks of 1,000 IDs.

o This list is managed and distributed by on-site Temperature Controls contractor.

• Zone controllers provided in this project shall have a digital display with temperature and humidity. A center setpoint of 72 degrees with +/- 5 degrees allowable control.

• Provide graphics to all points on front end supervisor (at the N4 level) o AUTO and OVERRIDE flags for OPERATOR o SET flags for ADMIN o EMERGENCY OVERRIDE & AUTO flags shall be hidden for all users o CFM Setpoint, Discharge Air Pressure Setpoint, Humidity Setpoint points shall only be editable by ADMIN o Zone Setpoint, Discharge Air Temperature Setpoint, Humidity Setpoint for all users o Analog Inputs shall have all flags hidden o Analog outputs shall have OVERRIDE and AUTO flags only o Digital outputs shall have ACTIVE / INACTIVE / AUTO flags o Digital inputs shall have all flags hidden o Effective Setpoints (setpoint plus/minus thermostat offset) shall also be shown for all graphics.

o Systems with a Reset Schedule shall have SET / OVERRIDE / AUTO for high/low/effective setpoint for ADMIN only. OVERRIDE / AUTO only for effective setpoint for OPERATOR, all other flags hidden.

o Floor Plans shall be created showing room boundaries and numbers:

▪ Greater than or equal to 4 degrees above setpoint shall highlight the effected zone RED.

▪ Greater than or equal to 4 degrees below setpoint shall highlight the effected zone BLUE.

▪ Zone Temp / Humidity / Effective Setpoint shall be included on each zone.

▪ Each zone shall link to a device graphic showing the VAV box controls.

• Remote access is not allowed for any BAS system.

• Contractor access to BAS system:

o MAC address of ethernet card for the PC/Laptop to be used during this project shall be provided to AC Shop Supervisor to allow access to network. AC Shop Supervisor to create ticket with OI&T and will provide IP address to be used to access the system.

o Username/Password will be provided by AC Shop Supervisor for access to front-end.

Freeze Protection Devices and Averaging Sensors

• Freeze Protection and Averaging Sensors used shall encompass the entire face of the coil.

o There shall be no more than 12" between u-bends on the same side of a coil. If capillary tube length cannot cover entirety of the coil, then multiple freeze protection devices or averaging sensors shall be used.

12"

12" o For averaging sensors, use an average of the sensors for the analog input. For example, a Chilled Water coil consisting of two averaging sensors reading 51° F and

54° F will average to 52.5° F for use in Sequence of Operations.

o Freeze stats shall be mounted outside the Air Handling Unit (AHU) if in a temperature-controlled space. If they cannot be mounted outside the unit because the unit is outdoors, they shall be mounted to the inside wall of the AHU closest to the access door.

o Freeze stats shall be tested with freeze spray or ice and physically apply to 12 ̋-18 ̋ of the serpentine copper tubing that holds the temperature-sensitive gas vapor. The gas vapor pressure will drop and cause the freeze stat to trip. Verify the sequence of operations that occurs or that is supposed to occur when the freeze stat trips. This will typically include a shutdown of unit fans, closing of the outdoor air damper, closing of all humidifiers throughout the system, and an opening of the hot water valve. SOO may vary depending on application.

o Freeze stats must also be mounted in a place they can be reached to reset without the use of a ladder.

Differential Pressure and Static Pressure Control Devices

• Differential pressure transducers for Dirty Air Filter status must match the range for the design filter pressure drop rating. This shall be tested and verified to that setpoint.

• Static Pressure safety cutout switches must be tested and verified to design.

o Manual reset switches.

Control Actuators

• Valve actuators must provide visual and electronic position feedback. Incorporate position feedback to BAS.

• Actuators must be proportional control type, 2-10 VDC.

Control Actuators for 2” or larger piping

• All electronically controlled actuators that are outdoors must be housed in NEMA 4 rated enclosures

• Valve actuators must have manual override wheel handle to open or close valve in case actuator failure

• Valve actuators must provide visual and electronic position feedback. Incorporate position feedback to BAS.

• Actuators must be proportional control type, 2-10 VDC.

Control Transformers

• Provide control transformers with internal overload protection with manual reset.

VFDs

• Bypass must have BACnet communication

• Serially monitor amps, kWHrs, operating mode, etc – even in bypass mode

• VFDs for Air Handling Units must be tied into fire shutdown, even during bypass operation must shut down with Fire/Smoke alarm

Outdoor Electronics

• All electrical components, conduit, and boxes that are outdoors must be housed in NEMA 4 rated enclosures.

• NEMA 3R may be used for electrical disconnects. Conduits shall be sealed to prevent moisture migration to sensitive electrical components.

Cooling Towers

• Tower Shell Composed of Anti-microbial HDPE Resin

• Fully Compounded Throughout Resin

• Resists Biofilm Growth

• Withstand Most Aggressive Chemical Treatments

• Install sump bypass for each tower with isolation valves

• Install basin equalizer lines with isolation valves

• Install two in-line basket strainers with isolation valves o Isolation valves electronically controlled.

o Install differential pressure sensor across strainers o Allow for BAS control of actuators to swap strainers.

Freeze Protection

• Fill systems with 30 percent propylene glycol for freeze protection.

OR

• Install heat trace for all outdoor piping.

OR

• Sequence BAS operation for freeze protection (if system is on emergency generator backup power)

Pipe Insulation

• Fiberglass insulation on all piping.

• All outdoor insulation shall also be covered with embossed, aluminum jacketing.