HSI Mechanical, Inc. is a Heating, Ventilation, and Air Conditioning (HVAC) & Plumbing contractor serving commercial and government customers, tracing its roots to the 1944 founding of Pacific Marine & Supply Company, Ltd. Recognizing the need for more efficient mechanical systems in response to the 1970’s oil crisis, HSI Mechanical was formed as a subsidiary of Pacific Marine in 1974. HSI quickly established itself as an early-adopter of and specialist in energy-saving building-automation systems.

With over 50 years of experience, HSI Mechanical is proud to have installed and maintained mechanical systems across Hawaii for some of the state’s largest organizations. Our clients span key industries including Healthcare, Hospitality, Retail, Education, and the Military—serving facilities at the Commercial, Federal, State, City & County levels.

Energy efficiency is at the core of our mission. We continue to provide customers with the most efficient equipment available and ensure optimal performance through expert maintenance and service.

As a proud signatory of both the Plumbers and Fitters Union Local 675 and the Sheet Metal Workers International Association Local 293, HSI Mechanical is built on the expertise of highly trained, safety-focused tradespeople—many of whom have been valued members of our team for decades.

We are deeply committed to our local community. Our leadership and staff actively participate in a wide range of local associations and nonprofit organizations, reflecting our dedication to giving back and supporting the people and places we serve.

License ABC-24578, with specialty licenses in C-37: Plumbing, C-44: Sheet Metal & C-52: Air Conditioning