The facility HVAC system is operated by a Trane Summit Building Automation System (BAS) that was installed along with chiller units in 2000. Heat for the building is supplied by a Con-Edison steam main that enters through a station located in the building’s sub-basement. The high-pressure steam is utilized to power the building’s absorption chillers, various-air handling unit preheat and heating coils, as well as for steam-to-water heat exchangers that provide heating water to perimeter induction units. The pressure is lowered by pressure reducing stations at multiple locations. Condensed steam is returned through a condensate piping system.

A chiller plant located in the penthouse mechanical room provides chilled water for cooling. Cooling is done by two Trane 380-ton steam powered, lithium bromide, absorption chiller units that are located at the penthouse level. Heat rejection for the chillers is by an upper penthouse level Marley Doubleflow Aqautower cooling tower originally constructed in 1962 and rebuilt in 1999-2000. The chillers have dedicated chilled water and condenser water horizontal split case Weinman pumps driven by Baldor 40-HP and 20-HP electric motors. Each chiller has a nominal rating of 380 tons and uses R-22 as a refrigerant. The chiller units, associated pumps and other related components were installed in 2000. The cooling tower components were refurbished in 1999-2000 and have new PVC fill, stainless steel basin and decks, valving, motors and gear boxes. The building features two roof-level cooling towers, each with a capacity of 2,500 tons.

Circulating pumps provide hot and chilled water to each temperature-controlled space by a two-pipe distribution system. Water from the cooling tower can be used for cooling during seasons of moderate temperatures. The hot and chilled water supplies the fan coil units located on the perimeter walls.

Air distribution is by two systems, interior and perimeter, that are divided into low-rise and high-rise zones. The interior areas are served by air handling units, which have been converted to a variable air volume (VAV) system. There are a total of seven air handling units which serve various areas of the building. The low-rise zone is served by two units, with one handling the interior areas and the other handling the perimeter areas. The high-rise zone is served by two more units. The fifth and sixth handling units serve the concourse, basement and retail units, as well as the lobby level. A final unit serves the sub-basement level.

The perimeter areas are served by a two-pipe perimeter induction system. There are approximately 40 to 50 perimeter induction units (PIU) per floor at the lower floors and approximately 30 PIUs per floor on the smaller upper floor areas. The units are located within cabinets at the floor along the outside wall. Room air is circulated through grills on the top of the cabinets. Two supply risers, north and south, supply air to the induction units. The coils in the induction units are supplied with heated or chilled water by a secondary water system and each unit has an individual knob-controlled thermostat.

Stairwells, bathrooms, and other areas are ventilated by mechanical exhaust fans. Large capacity ventilation fans, mounted on the roof, are connected by concealed ducts to each ventilated space.

The electrical supply lines run underground with incoming service from West 40th Street. Electricity to the building is supplied from underground feeders to the main switch gear at the meter room located at the sub-basement level. The main electrical service for the building is provided by a single central terminal and is 20,000 amperes and 277/480 volt with three-phase four-wire alternating current. Electrical wiring is copper installed in metallic conduit.

Electrical service to each tenant unit ranges between a minimum of 200 amperes and a maximum of 600 or more amperes. Commercial units are sub-metered, with circuit breakers housed in each level’s electrical closet. Circuit breakers individually supply each unit’s HVAC system, appliances, and receptacles. Tenant units also include incandescent and fluorescent light fixtures.

A diesel-powered 125 KVA emergency electrical generator is located in the sub-basement, which provides back-up power for components of the fire and life safety systems. The corresponding fuel tank is an above-ground tank located adjacent to the generator.