C-4

Boiler, Hot Water & Steam Contractor Verification - Page 3

710 boiler, hot water & steam contractors checked against 6 data sources (Page 3 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 101-150 of 710

A C CORPORATION OF NORTH CAROLINA

Clear

License #491941 · GREENSBORO

QUAL Bond SUSP

A C I MECHANICAL INC

Clear

License #821570 · AMES

Active

A G C INC

Clear

License #780352 · CAMPBELL

Active

A K P BOILER TECH

Clear

License #1075474 · CERRITOS

Active

A M C BOILERS

Clear

License #1049390 · HUNTINGTON PARK

Active

A M S HEATING INC

Clear

License #767349 · STOCKTON

Active

A O REED & CO LLC

Clear

License #7731 · SAN DIEGO

Active

A T S PLUMBING AND BOILER

Clear

License #466960 · SAN JOSE

Active

A/C DOCTORS TV INC

Clear

License #981124 · OCEANSIDE

Active

ACCO-WILSON, INC

Clear

License #1042403 · PASADENA

Active

ACE BOILER CO

Clear

License #863472 · NORCO

Active

ACE PLUMBING & ROOTER

Clear

License #829071 · SAN FRANCISCO

Active

ACTION APPLIANCE SERVICE

Clear

License #944327 · BELLA VISTA

Contr Bond Susp

ADVANCED HEATING AND COOLING INC

Clear

License #976708 · BURBANK

Active

ADVANCED REFRIGERATION

Clear

License #1017769 · OAKLAND

Active

AERCO SYSTEMS LLC

Clear

License #1084381 · SAN DIEGO

Active

AES INDUSTRIAL INC

Clear

License #1049754 · PASADENA

Active

AFTERGLOW HYDRONIC HEATING

Clear

License #1135450 · BERKELEY

Active

AHRENS MECHANICAL

Clear

License #957287 · SAN DIEGO

Active

AIR CONDITIONING COMPANY INC

Clear

License #819862 · PASADENA

Active

AIR MECHANICAL

Clear

License #881311 · CITY OF INDUSTRY

Active

AIR PLUS

Clear

License #573122 · VAN NUYS

Active

AIR TEMPERATURE SPECIALISTS

Clear

License #763576 · TEMECULA

Active

AIR-EX AIR CONDITIONING INC

Clear

License #418759 · POMONA

Active

AIRCON ENERGY INC

Clear

License #962305 · GOLD RIVER

Active

AIRITE HEATING AND AIR CONDITIONING INC

Clear

License #232930 · ONTARIO

Active

AIRTEC SERVICE

Clear

License #661643 · WATSONVILLE

Active

AJAX PLUMBING

Clear

License #745896 · EL DORADO HILLS

Active

ALAMEDA ISLAND HEATING & AIR CONDITIONING LLC

Clear

License #889253 · ALAMEDA

Active

ALASKA REFRIGERATION AIR CONDITIONING & HEATING CO

Clear

License #565401 · OAKLAND

Active

ALL AREA SERVICES

Clear

License #904020 · LOS ANGELES

Active

ALL GREEN SYSTEMS GO

Clear

License #878503 · LAFAYETTE

Active

ALL TRADE MECHANICAL AND ELECTRIC

Clear

License #997724 · MOUNT SHASTA

Active

ALLIED ENGINEERING & FIRE PROTECTION SERVICES

Clear

License #514420 · NEWPORT BEACH

Active

ALPHA AIR CONDITIONING & HEATING INC

Clear

License #896570 · SUNLAND

Active

ALPHA REFRIGERATION & AIR CONDITIONING INC

Clear

License #987446 · CANYON COUNTRY

Active

ALSD MECHANICAL

Clear

License #1127737 · PITTSBURG

Active

ALTERNATIVE ENERGY

Clear

License #632507 · SONORA

Active

AM MECHANICAL LLC

Clear

License #1037938 · DOWNERS GROVE

Active

AMERICAN AIR SYSTEMS INC

Clear

License #798465 · VACAVILLE

Active

AMERICAN BUILDERS

Clear

License #427930 · SONOMA

Active

AMERICAN CONTINENTAL ENGINEERING CORP

Clear

License #659654 · GARDEN GROVE

Active

AMERICAN INCORPORATED

Clear

License #292529 · VISALIA

Active

AMERICAN MECHANICAL; IQ CONTROLS

Clear

License #883177 · WALNUT CREEK

Active

AMERICAN RADIANT & WATER HEATING INC

Clear

License #1102680 · WINDSOR

Active

AMERICAN WATER HEATER SERVICE INC

Clear

License #959436 · NEWARK

Active

AMERINE SYSTEMS INCORPORATED

Clear

License #493203 · OAKDALE

Active

ANDERSON RADIANT HEATING

Clear

License #718718 · CAMPBELL

Active

APCOMPOWER INC

Clear

License #646278 · PASADENA

Active

APEX PLUMBING & HEATING INC

Clear

License #898328 · SALINAS

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.