Remove and replace stack cap on boiler # 2 with larger diameter. Replace tie down cables and hardware on 4 boiler stacks above the roof. Remove 2 each existing motor driven and 2 each non motor driven exhaust fans on the roof and replace with new motor driven fans. New fans are to be same style as existing motor driven fans with 14,000 CFM's per fan. Fans must fit existing openings and motors are to be 3 phase 480 volts. Install new starter motor control and breakers for each new fan. Run new rigid conduit to each fan from new motor controls and install new waterproof disconnect at each fan on the roof. Pull new wires and make all necessary connections. Test equipment for proper rotation and operation. Remove existing double doors on the west side of B. 644 and install new louvers with insect screen to match other existing louvers on the east side. Paint lew louvers to match existing louvers.