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Washington Master HVAC/Refrigeration - Restricted (6B) License

The Master HVAC/Refrigeration - Restricted (6B) License allows you to do the following work:

  • Supervise electrical work and electricians on the following:
    • Installation, repair, replacement, or maintenance of HVAC/refrigeration:
      • Telecommunications
      • Class 2 low-voltage control circuit wiring/components in other than residential occupancies that have no more than three stories on/above grade
  • Excluded from:
    • Performing any electrical work where the primary electrical power connection to the HVAC/refrigeration system exceeds 250 volts, single phase, or 120 amps
    • Installing, repairing, replacing, or maintaining the allowed telecommunications/low-voltage HVAC/refrigeration wiring in a conduit/raceway system

How to Get the Master HVAC/Refrigeration - Restricted (6B) License in Washington?

  1. Meet the requirements necessary for the certification level:
    • Have an electrician certificate issued by the department for at least two years
  2. Obtain the following information before doing the application process with PSI©:
    • Social Security Number
    • Mailing address
    • Email address
    • Corresponding fees
  3. Fill out and submit the Application for the Master HVAC/Refrigeration - Restricted (6B) Examination along with all the previous documents, to:
    Electrical Program
    PO Box 44460
    Olympia, WA 98504-4460
    The Washington State Department of Labor & Industries allows candidates to apply in person. Please refer to the list of local offices before visiting
  4. Expect a notice by mail from the Labor & Industries department and instructions on exam scheduling once the application is reviewed
  5. Take and pass the examination. For more information on the subjects and study material needed to prepare for the exam, refer to the Candidate Information Bulletin
  6. Complete a Change Assignment of Master Certificate form to be assigned to an electrical contractor and submit it with the corresponding fee

Washington Master HVAC/Refrigeration - Restricted (6B) License Exam Prep Courses

Washington Master HVAC/Refrigeration - Restricted (6B) License Exams

Below is all the information related to the trade and WA Codes exams, including the official reference lists.

Washington Master HVAC/Refrigeration - Restricted (6B) Trade Exam

  • Testing Method: Computer-based testing
  • Testing Company: PSI©
  • Number of Questions: 34
  • Types of Questions: Multiple choice
  • Time Allowed: 180 Minutes
  • Minimum Passing Score: 70%
  • Subjects Involved (No. of Questions):
    • NEC 90 - Introduction (1)
    • NEC 100-110 - General Requirements (3)
    • NEC 240 - Overcurrent Protection (4)
    • NEC 250 - Grounding & Bonding (4)
    • NEC 300-398 - Wiring Methods (5)
    • NEC 400-427, 455-480 - Electrical Equipment (2)
    • NEC 430-450 - Motors, HVAC, Generators & Transformers (5)
    • NEC 500-516 - Hazardous Locations (1)
    • NEC 705-780 - Special Conditions (3)
    • General Trade Knowledge & Theory (6)
  • PSI© Master HVAC/Refrigeration - Restricted (6B) Official Content Outline

Washington Master HVAC/Refrigeration - Restricted (6B) WA Codes Exam

  • Testing Method: Computer-based testing
  • Testing Company: PSI©
  • Number of Questions: 20
  • Types of Questions: Multiple choice
  • Time Allowed: 60 Minutes
  • Minimum Passing Score: 70%
  • Subjects Involved (No. of Questions):
    • Washington Laws & Rules (RCW & WAC) (20)
  • PSI© WA Codes Official Content Outline

Washington Master HVAC/Refrigeration - Restricted (6B) Book Set

This set of books includes all required references for the Master HVAC/Refrigeration - Restricted (6B) and WA Codes exams. Orders placed before 2 PM are shipped the same day via UPS and a tracking number is emailed before 3 PM.

  • WASHINGTON MASTER HVAC/REFRIGERATION - RESTRICTED (6B) - BOOK SET WITHOUT TABS INCLUDES ALL BOOKS FOR TRADE AND BUSINESS EXAMS

    Sales price: $349.45

  • WASHINGTON MASTER HVAC/REFRIGERATION - RESTRICTED (6B) - BOOK SET WITH TABS INCLUDES ALL BOOKS FOR TRADE AND BUSINESS EXAMS

    Sales price: $399.45

Washington Master HVAC/Refrigeration - Restricted (6B) Exam Books

Books Allowed in Testing

Washington Master HVAC/Refrigeration - Restricted (6B) WA Codes Exam Books

Books Allowed in Testing

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