Plan Review Comments, 7 World Trade Center, 1998

NYC 9/11 Public Portal Document

C. DWG. M 1.23:

1. CW flow diagram does not conform to the floor plan. All zoning automatic valves must be shown correctly on floor plan. Provide an automatic valve operating sequence schedule on drawing with collaborating designations on the floor plans.

2. The AC units are balanced to receive only fixed amounts of water under normal operations, based upon using a 11F delta condenser water, but a 19F delta- T using the emergency tower would result in lower flow rates through the same units. Such lower flow rates would certainly reduce cooling capacities of the units, if not Immediate malfunctioning. Please review and verify.

3. Provide house keeping pads for condenser water pumps.

4. Provide a detail to show bottom of plenums pitch toward to prevent Infiltration.

5. Sequence of operation for condenser water system and fan power boxes.

D. DWG.M4.01:

1. Complete ventilation Index as per Port Authority standards.

2. Indicate minimum setting for alt VAV Boxes.

3. Provide a cooling tower schedule and details.

4. The tower specification shows an operating range of 19F delta-T, from 89F to 108F for 130 GPM each. The AC unit schedule shows 12.5F delta-T for three units and 11F delta-T for other new units. There is no sufficient data presented in these drawings to evaluate that this arrangement would work out under the emergency condition. (Also see related comments above.) All new units should be selected to operate adequately under emergency conditions. 5. Adi AC units should be provided with temperature and pressure gauges.

6. Specify vibration isolators in the pump schedule.

8. Provide FSD details. Gate type fire damper no longer complies with the code. VAV’s not Building Standard

NYC-WTC_6oO 173478