Contractor Lookout is an independent website, not affiliated with CSLB or the State of California. This record comes from CSLB's public data file dated November 1, 2026 and may be out of date. Not a consumer report under the FCRA.
McMaster Mechanical: CSLB License #879152
Source: CSLB public data · Updated November 1, 2026 · Official CSLB record
Verify live status on CSLB's Instant License Check before hiring.
Verify live on CSLB Report an error / remove my address
The license is active with no suspension on record, though classifications, bonds and secondary flags still deserve a look.
License details
- License number
- 879152
- Primary status
- CLEAR · what this means
- Business type
- Corporation
- Issued
- June 10, 2006 (20 years)
- Reissued
- February 22, 2021
- Expires
- February 28, 2027
- Inactivated
- June 27, 2011
- Reactivated
- May 6, 2016
- Classifications
- C-20 Warm-Air Heating, Ventilating and Air-Conditioning Contractor
- Mailing address
- 20903 Ambushers Street, Diamond Bar, CA, 91765
- Phone
- (714) 497 0225
Workers' compensation
- Type
- Workers' Compensation Insurance
- Insurer
- Continental Casualty Company
- Policy number
- WC739300966
- Effective
- June 1, 2026
- Expires
- June 1, 2027
Confirm coverage with CSLB's insurer search. How to check workers' comp.
Contractor's bond
- Surety
- American Contractors Indemnity Company
- Bond number
- 101095205
- Amount
- $25,000
- Effective
- September 8, 2026
Status history
No changes recorded since we began tracking this license on November 1, 2026. We compare every weekly CSLB file and log changes to status, bonds, workers' comp and classifications here.
Related
- Licensed HVAC contractors in Diamond Bar
- Licensed contractors in Diamond Bar
- Contractors in Los Angeles County
- What "CLEAR" means
- How to check a contractor license
Data: CSLB Public Data Portal, file dated November 1, 2026. Status can change at any time. Verify on CSLB's Instant License Check. This site is not a consumer reporting agency under the FCRA; don't use it for employment, credit, insurance or housing decisions about an individual.