A firm of experienced Project Managers and top-tier field technicians specializing in a wide range of commercial and industrial HVAC/R services and projects.


Diversified Thermal Services, Inc. was founded in 1990 by President and CEO Craig Steinmetz, specializing in the service and construction sectors of the Commercial and Industrial HVAC/R industry. Since 1990, we have extended our reach and expertise by creating and fostering a Building Automation department, making Diversified Thermal a unique all-encompassing mechanical contractor that can provide a turnkey solution for any Commercial HVAC or Industrial Refrigeration project.

Our management team is comprised of the most innovative and mechancial minds in the industry. These skills have been developed through our management staff’s extensive hands-on, in field mechanical experience, giving them the valuable and relevant industry knowledge and insight required to deliver the most effective and efficient solutions to our continually growing customer base.

With this expertise in our support staff, we empower our field employees with the tools and knowledge that they need to deliver for our customers. We take pride in the services we offer and will always stand behind our product and our people.

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Our mission is to create customers for life through exceptional customer satisfaction by implementing safe, innovative, and efficient HVAC solutions and services. We actively promote professionalism and unparalleled quality, by empowering our people to deliver a premier product that adds value and longevity to our customer’s assets.

Unparalleled Customer Service
Prompt and Timely Project Completion
Accountable and Reliable Technical Support
Unmatched 24/7/365 Emergency Response
Impeccable Company Safety Record
Customer Training and Education


Diversified Thermal serves a multitude of vertical markets within the HVAC/R space. Here are just a few of the high profile customers we serve in these markets.


707 Wilshire 777 Figueroa
One Cal Plaza Two Cal Plaza
CB Richard Ellis The Irvine Company
Howard Hughes Center South Coast Plaza
Capital Group Mar Ventures


Mission Hospital St. Joseph’s
Kaiser Permanente UCLA Medical Center
Cedar Sinai VA Hospital
St. Mary’s Medical Palo Verde Hospital
Loma Linda Pomona Valley Hospital


UC Irvine Cal State Fullerton
Orange Coast College Mt. San Antonio College
Cypress College Golden West College
UC Riverside The Clairmont Colleges


Irvine Unified School District Pasadena Unified School District
El Monte Unified School District Montebello Unified School District
Buena Park Unified School District Rosary High School
Santa Margarita Catholic High School St. Bonaventure
Chaffey Joint Union School District St. Columban School


Jazz Semiconductor Kinder Morgan Energy Partners
Consolidated Container Company Driftwood Dairy
Gold Coast Bakery Bocchi Labs
JPL Conoco Phillips
Valero Seneca


Boeing Hughes Aircraft
Raytheon Arrowhead Products
LAX International


ARCO Valero
Texaco Chevron
Tesoro BP


San Diego Blood Bank Bocchi Labs
Mellanox Watson Laboratories
The Gas Company [Bldg H] Example6


Southern California Edison The Gas Company


Hyatt Hilton
Montage Resort St. Regis
Marriott Ritz Carlton
Marriott Residence Inn Long Beach Convention Center
LA Convention Center Dodger Stadium


Disneyland Knott’s Berry Farm
Universal Studios Paramount Studios
Staples Center Honda Center


Staples Center Honda Center
M&M’s Center | Sheridan, WY Anaheim Ducks The Rinks
Ice Town Riverside Center Ice Ontario
Pasadena Ice Rink Aliso Viejo Ice Palace
KHS Ice Arena LA Kings Valley Ice Center


Coast Tropical Davalan Sales
Banana Company U.S. Foods
Olympic Fruits and Vegetables Sato and Co.
Moraga Vineyards Consolidated Container Company