Garrett Jacobs Mansion

The Garrett-Jacobs Mansion is a historic, four-story home in the Mount Vernon neighborhood of Baltimore, Maryland. Built in the late 1800s, the celebrated building — preserved by state historical easements — has been home base for the Engineering Society of Baltimore, Inc. (Engineers Club) since 1961.

A few years ago, the Engineers Club realized visitors required more accessibility to the upper floors of the mansion as well as a streamlined HVAC system. The Club decided to build an adjacent 5,600-square-foot tower that connects to the building, providing access to an elevator, stairs, accessible washrooms and additional storage.

Having a long-standing relationship with the Engineers Club, Smiley El-Abd, commercial area manager, Mitsubishi Electric Trane HVAC US (METUS), worked with distributor, Aireco Advanced Products Group, to provide CITY MULTI® Variable Refrigerant Flow (VRF) to serve both the new building and parts of the restored mansion.

The Vertical Expansion

The project, known as the “vertical expansion” has been years in the making. Cory Colassard, vice president of Spears/Votta & Associates, Inc., and the engineer responsible for the HVAC design, explained that the new VRF system is part of a plan to modernize the mansion’s heating and cooling systems. “This project is an opportunity to improve the building, improve operating costs, give the Engineers Club flexibility and allow them to have individual temperature control in multiple rooms,” noted Colassard. “It’s an improvement that’s generating a master plan for moving forward instead of putting a bandage on the conditioning issues as they arise.”

“When we started, there was no vision for conditioning needs. We came in with VRF and now the Engineers Club can envision how the building is going to work for the next 100 years,” explained El-Abd. “With historical buildings, it is so common that a person will add on one system, then another will choose a different one…which can have some negative implications. With Mitsubishi Electric, it’s so easy. You can expand the system as needed while tying everything into one integrated controls system.”

A New Plan for Comfort

Ultimately, Mitsubishi Electric’s R2-Series system with a Lossnay® Energy Recovery Ventilator (ERV) was selected for the vertical expansion tower — a four-story, light steel structure. In addition to the tower, the new system conditions some rooms on the second floor of the mansion, areas that previously did not receive conditioning or modern ventilation.

Both ducted and ductless units were installed in the mansion and the tower. Additionally, the building recently upgraded its dated controls system to the AE-200A Centralized Controller, giving the Engineers Club staff precise management of the facility for both day-to-day operations and events.

As for continued VRF expansion, El-Abd is confident the Engineers Club will continue to reap the benefits of switching its HVAC systems. “VRF significantly reduces the heating load calculations. At the mansion, people can rent out various rooms, people can utilize the Club bar…with zoning, the air handlers will serve the specific zones in use.”

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