C-4

Boiler, Hot Water & Steam Contractor Verification - Page 10

710 boiler, hot water & steam contractors checked against 6 data sources (Page 10 of 15)

About C-4 License

Boiler, hot water heating, and steam fitting contractors.

710

Total Contractors

695

Active Licenses

97

Federal Records

Verify a Boiler, Hot Water & Steam Contractor

Boiler, Hot Water & Steam Contractors

Showing contractors 451-500 of 710

MADCON BUILDERS

Clear

License #1146541 · GUERNEVILLE

Active

MADCON INC

Clear

License #584874 · HEALDSBURG

Active

MALCOLM PLUMBING & MECHANICAL

Clear

License #885680 · SAN FRANCISCO

Active

MAPLES WAYNE PLUMBING & HEATING INC

Clear

License #747665 · EUREKA

Active

MAPLESERVICE INCORPORATED

Clear

License #767710 · EUREKA

Active

MARIN MECHANICAL II INC

Clear

License #749299 · SAN RAFAEL

Active

MARINA MECHANICAL SERVICES

Clear

License #416198 · LIVERMORE

Active

MARINA PLUMBING & HEATING

Clear

License #574447 · MARINA

Active

MARINE & INDUSTRIAL SERVICES INC

Clear

License #534970 · ANTIOCH

Active

MASTERSON BRYAN ENTERPRISES

Clear

License #271933 · PETALUMA

Active

MATRIX HG INC

Clear

License #812232 · CONCORD

Active

MAYA'S BOILERS INC

Clear

License #1023703 · LA VERNE

Active

MC DONAGH JOHN BUILDERS AND ENERGY SYSTEMS

Clear

License #422946 · CASTRO VALLEY

Active

MC DONALD O C CO INC

Clear

License #177271 · SAN JOSE

Active

MC KENNEY'S AIR CONDITIONING INC

Clear

License #447218 · BAKERSFIELD

Active

MCCLOSKEY MECHANICAL CONTRACTORS INC

Clear

License #1053014 · BLACKWOOD

Susp - No Qualifier

MCDONALD MECHANICAL

Clear

License #1124892 · UKIAH

Active

MCKENNA BOILER WORKS INC

Clear

License #1044490 · OCEANSIDE

Active

MCNULTY MECHANICAL INCORPORATED

Clear

License #494419 · MODESTO

Active

MCR PLUMBING INC

Clear

License #707514 · CAMARILLO

Active

MECHANICAL SERVICES LLC

Clear

License #1007708 · LIVERMORE

Active

MEHRA HEATER & BOILER SERVICE

Clear

License #430220 · WEST COVINA

Active

MERRILL GEORGE CONSTRUCTION SERVICES

Clear

License #1028696 · SANTA ROSA

Active

MEYER C R AND SONS COMPANY

Clear

License #771491 · OSHKOSH

Active

MIKE'S HEATING & AIR INC

Clear

License #785004 · ANDERSON

Active

MILLENNIUM PACIFIC TRADING INC

Clear

License #928122 · SAN JOSE

Active

MILLER SCOTT M

Clear

License #1006302 · PETALUMA

Active

MODERN HYDRONICS

Clear

License #1044968 · OAKLAND

Active

MONTANO PLUMBING INC

Clear

License #621230 · SANTA CRUZ

Active

MONTOYA RADIANT HEATING CO

Clear

License #1137262 · FAIRFIELD

Active

MOON BOB HEATING AND AIR INCORPORATED

Clear

License #411700 · REDDING

Active

MOUNTAIN MECHANICAL COMPANY

Clear

License #1003956 · KERNVILLE

Active

MSR MECHANICAL LLC

Clear

License #1042634 · BENICIA

Active

MURRAY COMPANY

Clear

License #162382 · CYPRESS

Active

MURRAY PLUMBING & FIRE

Clear

License #824419 · REDDING

Active

N C B

Clear

License #1014257 · SPARKS

Active

N V HEATHORN CO

Clear

License #761659 · CONCORD

Active

NATHANIEL HUBER

Clear

License #1004514 · SANTA ROSA

Active

NATION RESTORATION LLC

Clear

License #1137994 · SACRAMENTO

Active

NATIONAL AIR & ENERGY

Clear

License #706889 · SAN DIEGO

Active

NATIONWIDE BOILER INCORPORATED

Clear

License #448144 · FREMONT

Active

NCM INDUSTRIAL SERVICES INC

Clear

License #830600 · CLOVIS

Active

NDI PLUMBING INC

Clear

License #889754 · RENO

Active

NEW ENGLAND SHEET METAL AND MECHANICAL CO

Clear

License #433674 · FRESNO

Active

NEW PIPES INC

Clear

License #906447 · PLEASANT HILL

Active

NEWCOMB MECHANICAL INC

Clear

License #699358 · SAN CARLOS

Active

NIEKRASZ PLUMBING INC

Clear

License #292370 · EUREKA

Active

NOOTBAAR PLUMBING INC

Clear

License #1073177 · MURRIETA

Active

NOR CAL MECHANICAL LLC

Clear

License #1012972 · GARBERVILLE

Active

NORTHERN DIGITAL INC

Clear

License #807306 · BAKERSFIELD

Active

How to Verify a Boiler, Hot Water & Steam Contractor (C-4) in California

California requires all contractors performing boiler, hot water & steam work valued at $500+ to hold a valid CSLB C-4 license. Of the 710 licensed boiler, hot water & steam contractors in the state, 98% currently hold active licenses and 13.7% have at least one federal compliance record.

Manual vetting takes 45+ minutes per contractor and routinely misses violations in databases most people don't know to check. SiteVetter runs CSLB status, SAM.gov debarment, DOL wage violations, OSHA safety citations, and EPA environmental records in seconds—creating a timestamped compliance artifact.

Verification Checklist for Boiler, Hot Water & Steam Contractors

  • Verify the contractor license is active and in good standing
  • Request proof of insurance and bonding
  • Get at least 3 written quotes before selecting a contractor
  • Check federal databases: SAM.gov, OSHA, DOL, and EPA records
  • Confirm bond: California requires $25,000+ contractor bond (SB 607)

Why Verification Matters for Boiler, Hot Water & Steam Work

Under California's "Controlling Employer" doctrine, general contractors face liability for subcontractor safety violations. For boiler, hot water & steam work specifically, 13.7% of licensed contractors have federal records that a standard CSLB license check wouldn't reveal. SiteVetter's 5-database check catches what a single-source verification misses.

Data sourced from California Contractors State License Board and federal databases. Updated weekly. For official verification, check directly with CSLB.