Solicitation Attachment - B466 Mechanical RFIs

B466 Mechanical RFI Responses
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Sheet M005, detail 2: The hot water piping diagram shows a 2-way modulating control valve for min flow control for the boiler. It’s location between the pumps and the boiler will not work. It will need to be located on the other side of the pumps. Also, there needs to be a flow meter for the control system to know how to modulate that valve to maintain min flow to the boiler. That flow meter needs to be in the supply line between the boiler and the bypass valve. Can you please confirm if this will be acceptable.
o DWG Response: In building 464, the heat pump boiler is only serving one piece of equipment (AHU-5) the 2-way modulating control valve is not required. Minimum flow to the boiler will be achieved upon a call for heat from AHU-5 and the associated 3-way modulating control valve before the heating coil. Please refer to the attached document showing the updated hot water piping diagram.
Sheet M106, detail 1: The B466 mechanical room renovation plan does not show an emergency stop switch for boiler shut down by the door. Is one required? o DWG Response: Yes, an emergency stop switch for the boiler shut down is required. Please locate it adjacent to the door.
Sheet M106, detail 1: There is no sequence of operation for the boiler and pump in B466. Can that be provided?
o DWG Response: Please see the attached document for the sequence of operation.
Sheet M007, detail 2: For AHU-5, there is no sequence of operation or list of control points necessary to complete that sequence of operation. Can that be provided? o DWG Response: Please see the attached document for the sequence of operation.
Sheet M007, detail 3: For AHU-1,2,3, and, 4, there is no sequence of operation or list of control points necessary to complete that sequence of operation. Can that be provided?
o DWG Response: Please see the attached document for the sequence of operation.
Sheet M105, detail 1: It is unclear if the chilled water valves need to be 3-way or 2way valves. Can you please clarify this? o DWG Response: The chilled water valves are required to be 3-way valves to maintain the functionality of the existing chilled water loop.

AHU-1, AHU-2, AHU-3 & AHU-4 SEQUENCE OF OPERATION

BAS

AHU-1, AHU-2, AHU-3 & AHU-4 SEQUENCE OF OPERATION:

T

P

T

T

P

M

T

FILTER

MIXING

BOX

OUTSIDE

AIR

OCCUPIED MODE (VAV):

IN OCCUPIED MODE, SUPPLY FAN SHALL BE ENABLED TO RUN THROUGH THE VARIABLE FREQUENCY DRIVE (VFD) AND SHALL RUN CONTINUOUSLY AND THE OUTSIDE AIR CONTROL DAMPER SHALL MODULATE TO MAINTAIN SCHEDULED OUTSIDE AIR VOLUME.