TAI was called upon to provide steam decentralization engineering services. The buildings’ heating systems were removed from the steam plant and provided with a gas service if none existed. Gas to hot water boilers were provided to serve heating water requirements. Buildings with steam duct coils were provided with hot water duct coils. Buildings with steam coils in the air handling units were provided with hot water coils or new air handling units with hot water coils. Steam units heaters were replaced with either gas-fired or hot water unit heaters. Steam radiators were replaced with either hot water or electric radiators. Existing condensate pumps were removed. Domestic water heaters older than 10 years were replaced with either new gas or electric water heaters.

Existing steam and condensate piping were removed back to the point of building entry. As selected by the government, existing exterior steam vaults were filled in and the surface made to match the existing. Buildings without adequate space for new boilers and hot water pumps were provided with exterior shelters. The shelters were designed per government specifications with poured concrete slabs, stud walls, sloped roofs, and wood siding. Mechanical ventilation, heat for the shelters, and floor drains connected to existing sanitary piping were provided. TAI provided mechanical, plumbing, electrical, architectural and structural design services for the shelters.

A typical heating water system consisted of two boilers capable of 2/3 of the heating load, two secondary hot water pumps (one of which is redundant), primary pumps integral to the boiler, variable frequency drives on motors 5hp and larger, expansion tank, air separator, and chemical feeder. The heating water systems were provided with new DDC controls. Buildings monitored by Pepco’s Energy management system were connected to this system.