Plan Review Comments, 7 World Trade Center, 1998

NYC 9/11 Public Portal Document

ALL H.V.A.C UNITS TO BE J.C.I METASYS BMS

B. Dwg. M1.07:

1. Emergency generator installation detail Is not correct. The exhaust pipe does not go to the roof of the building. Remove all references to roof as appropriate.

2. Generator exhaust pipes are shown to be terminated at the exhaust air plenum only. Since there is no specification provided specially for the exhaust plenum, we assume it is normal gauge sheet mefol. Please consider the following:

a. Exhaust pipes and mufflers are more than 900 F when the engines are running. Provide a detail to ensure proper sealing between the pipes and foe plenum at all temperature fluctuations. Otherwise, fumes would leak back into the building.

b. Provide calculation to prove that foe mix air of 900-degree engines exhaust and radiator exhaust is within the operating temperatures of normal sheetmetal plenum insulation and would create deformity to existing aluminum louvers along the building. Otherwise, please also consider venting exhaust pipe directly to outside, in a manner approved by foe Owner and Code compliance.

3. Please clarify why a circulating pump is required in foe fuel oil day tank. If it is meant to feed a header system, please provide details flow does it get mounted on foe day tank, its control schematics and how fois could be interlocked with foe rest of foe fuel oil system without creating over feeding conditions.

4. The entire engine exhaust piping and muffler should be vibration isolated (not specified) due to high velocity exhaust.

5. Exhaust pipes on floor plans have no size and are shown to have sharp 90- degree elbows. This will not work, as foe dynamic pressure of foe exhaust gas would destroy them. Please show long swing, smoofo-tuming, radius elbows instead. 6. Referenced to Architectural drawings, A-1-1: Provide a housekeeping pad for foe day tank. A curb may not be required since foe ta.ik is already had a leak proof basin on it. A curb may make cleaning around the tank difficult.

7. Leak detection for fuel and water to be at Johnson Controls Metasys.

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