• Steam was used to directly heat the air via the the main Air Handling Units
• Steam was converted to hot water for use in the building’s two-pipe system.
• Steam was used to generate domestic hot water via instantaneous hot water heaters.

HRG partnered with the general and mechanical contractors to provide design-build services as part of a Guaranteed Energy Savings Project. HRG’s design responsibilities included Mechanical, Electrical, Plumbing, Fire Alarm and Fire Protection engineering (“MEPS”).  HRG also hired architectural and structural engineering subconsultants to supplement the design package.  

The ESCO proposed a project to disconnect the building from the Veolia steam loop and serve the building with natural gas-fired steam boilers. Steam boilers simplify the connections within the building as existing outdoor air coils and the existing perimeter system are steam based. The project included three (3) Cleaver Brooks Boilers that connected into the existing steam system to serve the steam unit coils on AHUs and Induction systems and the existing steam to hot water converters. 

The boilers were sized so that a single boiler will support about 45% of the load. Two of the three boilers can provide coverage for all weather conditions except for an extreme condition in which the third boiler can be engaged. Strategies such as reducing outdoor air, or earlier start-up of systems help maintain the load in the building.

HRG’s Design Responsibilities Included:

• Preparation of MEPS demolition drawings for the removal of the existing steam systems and infrastructure;
• Review of the existing MEPS infrastructure present at the facility as required to support the addition of a new Steam Boiler Plant located in the Mechanical Penthouse;
• Preparation of MEPS design drawings for the proposed boiler plant;
• Development of boiler controls package that was integrated into the site’s new Building Automation System.

HRG’s Construction/Engineering Oversight Responsibilities Included:

• Review of Contractor Shop Drawings;
• Assist in responding to questions posed by the Contractors during the bid process;
• Provide necessary engineering support, as required, to resolve technical issues in the field, and to clarify the intent of the engineering design and technical specifications;
• Review and approve the appropriate information contained within requests for change orders and/or applications for payment;
• Attending site meetings as required by the Client;
• Served as the commissioning authority / third-party oversight to ensure the design-build team fulfills sustainability-design and equipment-testing requirements necessary to verifying overall function and performance

This project was successfully completed and put into operation in 2021.