| Employer | City | |
| Aaero Heating & Sheet Metal | Novato | View Profile |
| ACCO Engineered Systems | Glendale | View Profile |
| Air Plus Inc. | Van Nuys | View Profile |
| Air Systems, Inc. | San Jose | View Profile |
| Air Systems, Inc. | San Jose | View Profile |
| Air Treatment Corporation | City of Industry | View Profile |
| Airco Commercial Services, Inc. | Sacramento | View Profile |
| Aire Rite | Huntington Beach | View Profile |
| All Temperatures Controlled | Chatsworth | View Profile |
| Alternative Energy Resources | Various Locations | View Profile |
| Artic Mechanical, Inc. | Rancho Cucamonga | View Profile |
| Atlas Mechanical | San Diego | View Profile |
| Autodesk, Inc. | San Rafael | View Profile |
| Barr Engineering, Inc. | Santa Fe Springs | View Profile |
| Bay Air Systems | Concord | View Profile |
| Bergelectric Corp. | Escondido | View Profile |
| Bogner's All Air Inc. | Scotts Valley | View Profile |
| Building Comfort Services | Riverside | View Profile |
| C & L Refrigeration Corp. | Brea | View Profile |
| Christian Brothers Heating & Air Conditioning, Inc | Mira Loma | View Profile |
| City of Los Angeles | Los Angeles | View Profile |
| Coast Community College District | Costa Mesa | View Profile |
| Conditioned Air Mechanical Services | Various Locations | View Profile |
| Construct Corps | Various Locations | View Profile |
| Cooper Oates Air Conditioning, Inc. | Sacramento | View Profile |
| County Air | Orange | View Profile |
| Direct Energy - US Home Services | Various Locations | View Profile |
| Diversified Refrigeration Company | Valley Springs | View Profile |
| Dolan Foster Enterprises | Pleasenton | View Profile |
| Drymaxxair Solutions, LLC | Los Angeles | View Profile |
| DUCTMASTERS | Orange | View Profile |
| Emcor Group | Costa Mesa | View Profile |
| Emerson Climate Technologies, Retail Solutions | Various Locations | View Profile |
| Energy Controls Company | Discovery Bay | View Profile |
| EXCEL AIR CORPORATION | FALLBROOK | View Profile |
| Ferreira Service Inc. | Hayward | View Profile |
| First Service Networks | Various Locations | View Profile |
| Gentec Electrical Services | Livermore | View Profile |
| George T Hall Co Inc | Anaheim | View Profile |
| GMH Communities | Various Locations | View Profile |
| Guttmann & Blaevoet Consulting Engineers | San Francisco | View Profile |
| HBE Corporation | Various Locations | View Profile |
| Honeywell | Various Locations | View Profile |
| Ingersoll Rand Climate Control Technologies | Various Locations | View Profile |
| Integrated Engineering Services | Santa Clara | View Profile |
| Integrated Engineering Services | Santa Clara | View Profile |
| Jobelephant.com Inc. | San Diego | View Profile |
| Johnson Controls Inc, Building Efficiency | Various Locations | View Profile |
| Jones Lang LaSalle | Santa Clara | View Profile |
| KBR | Various Locations | View Profile |
| Koehler Plumbing, Inc. | Santa Maria | View Profile |
| Liebert Services | Various Locations | View Profile |
| Loma Linda University Medical Center | Loma Linda | View Profile |
| Manpower | Various Locations | View Profile |
| McQuay International/McQuay Service | Various Locations | View Profile |
| MEP Jobs - Customer Fulfillment | Various Locations | View Profile |
| Montage Laguna Beach | Laguna Beach | View Profile |
| NES Rentals Holdings, Inc | Various Locations | View Profile |
| NMI Industrial | Sacramento | View Profile |
| NORESCO | Various Locations | View Profile |
| Outsource Telecom | El Segundo | View Profile |
| Pacific Coast Trane Service | Sunnyvale | View Profile |
| Pacific Rim Mechanical | San Diego | View Profile |
| Pasadena City College | Pasadena | View Profile |
| Precise Air Systems, Inc. | Glendale | View Profile |
| PumpMan, Inc. | Baldwin Park | View Profile |
| R. J. Lanthier Co., Inc. | Escondido | View Profile |
| Ram Air Engineering | Lake Forest | View Profile |
| Rosendin Electric, Inc. | San Jose | View Profile |
| Sacramento Municipal Utility District | Sacramento | View Profile |
| San Jose/Evergreen Community College District | San Jose | View Profile |
| Service Logic | Various Locations | View Profile |
| Sheet Metal Workers Local 162 | Sacramento | View Profile |
| Southern California Edison Co | Rosemead | View Profile |
| TechSmart Air Conditioning, Inc. | Morgan Hill | View Profile |
| The J. Paul Getty Trust | Los Angeles | View Profile |
| The Linc Group | Various Locations | View Profile |
| Trane Commercial Systems | Various Locations | View Profile |
| Transwestern | Various Locations | View Profile |
| URS Corporation | Various Locations | View Profile |
| Val's Plumbing & Heating, Inc. | Salinas | View Profile |
| Weatherite Corporation | San Diego | View Profile |
| Wilson's Plumbing & Heating | Pacific Grove | View Profile |
| Xcel Mechanical Systems, Inc. | Gardena | View Profile |
| ZODIAC HVAC INC. | Van Nuys | View Profile |