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C-20 Licenses 101: How to Get Them, How Long It Takes + Resources

Published: July 06, 2022
Last updated: July 09, 2022
Read time: 5 minutes

As the demand for climate control systems rises, HVAC professionals will continue to be in higher demand. According to the US Bureau of Labor Statistics, employment of heating, air conditioning, and refrigeration mechanics and installers is expected to rise by 5% between 2020 and 2030. 

However, residential, commercial and industrial systems are becoming more complex, so more skilled HVAC professionals are needed. For that reason, it’s recommended for contractors to get a C-20 License. Here, we’ll walk you through the steps to obtain a C-20 License, its requirements, fees and the resources you need to help you prepare for the exams. 

What is a C-20 license?  

The C-20 HVAC License is a Class C Specialty Contractor License offered by the state of California, required to conduct legal operations in air conditioning projects, heating ventilation, and other climate control projects. It is required if you want to bid on residential or commercial heating, ventilation, or air conditioning projects with a labor and material cost of more than $500. 

The C-20 HVAC License is regarded as one of the most important licenses in public safety because it covers a broad range of technicalities. The Contractor State License Board (CSLB) is the governing body responsible for issuing a C-20 License. 

CSLB defines a C-20 HVAC contractor as “a warm-air heating, ventilating and air-conditioning contractor that fabricates, installs, maintains, services, and repairs warm-air heating systems, air conditioning systems, and water pumps. Complete with warm-air appliances; ventilating systems complete with blowers and plenum chambers; air-conditioning systems complete with air-conditioning unit; and the ducts, registers, flues, humidity and thermostatic controls and air filters in connection with any of these systems. This classification shall include warm-air heating, ventilating and air-conditioning systems which utilize solar energy.”

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How do I get a C-20 license?

To obtain a C-20 HVAC License, you must first meet the following basic requirements:

  • You must be at least 18 years old.
  • You must have a valid USA-issued ID or Driver’s License.
  • You must have a Social Security Number or TIN.
  • Not under any probation or parole due to a criminal case.

Aside from these basic requirements, you are required to comply with the following:

  1. Four years of experience as a Journeyman

Before you can take the C-20 License exam, you must have four years of experience working full time for an HVAC company without any supervision or under the supervision of a contractor who holds a C-20 license. The CSLB requires four full-time years over the last ten years – it doesn’t have to be consecutive, as long as you have four years before the exam date. You can take three years of experience from an approved college or vocational program and at least one year in fieldwork.

If you lack the four years of required journeyman-level experience, you can obtain it through an apprenticeship program. The California Department of Industrial Relations offers online resources to help you find an apprenticeship program through a local union or Joint Apprenticeship Training Committee (JATC).

  1. A qualified individual to sign your experience

To validate that your experience is credible, you must have the signature of a qualified individual. They can be a fellow employee/journeyman, former supervisor, foreman, business associate, licensed general contractor, or C-20 license holder.

Your chosen qualified individual must have seen or observed how you work, and they should provide a brief description of your capabilities and skill set in the field. To do so, they must fill up the experience certification of the application form. The written description must be detailed – including the installation, repairs, or other tasks you have performed. The CSLB is crucial with your reference description, so it is a huge factor in getting accepted.

  1. Documentation of your experience.

You must prepare supporting documentation of your experience in contracts, check stubs, material invoices, and tax returns, as mandated by the Contractors State License Board – they do not accept pictures of projects or group documentation.

Once you have the work experience and documentation needed, you can now apply to sit for the CSLB Contractors License Exam. You must fill out a form to apply for the tests. 

There are three options for completing the form. You can fill out an online form, print it and mail it to CSLB with the $450 fee, print a blank form, fill it out and mail it to CSLB with the $450 fee, or receive a blank form by mail, fill it out and mail it to CSLB with the $450 fee.

  1. Pass two state exams

To obtain a C-20 license, you must pass two state exams: The Class C-20 License Examination and the Law and Business Exam. 

The C-20 License Examination has four major sections: 

  • Evaluation, Design and Estimation
  • Fabrication
  • Installation and Startup
  • Troubleshooting
  • Repair and Maintenance, and Safety. 

The Law and Business Examination has eight major subjects: 

  • Business Organization
  • Business Finance
  • Employment Requirements
  • Bonds
  • Insurance and Liens
  • Contract Requirements and Execution
  • Licensing Requirements
  • Safety and Public Works.

The C-20 license exam will be multiple choice and close book, administered on a computer at a CSLB testing facility. There are facilities in Berkeley, Fresno, Norwalk, Oxnard, Sacramento, San Bernardino, San Diego, and San Jose. You’ll be given three hours to complete each section, which will include the following:

  • 115 Questions of Contractor Law and Business
  • 115 Questions on HVAC
  1. Complete criminal background check

To obtain a C-20 License, you must complete a criminal background check and disclose any criminal pleas or convictions. In addition, you must submit to fingerprinting in accordance with California law. The CSLB will be notified if you are convicted of a crime, such as DUI or other Vehicle Code violations. However, it doesn’t disqualify you from getting a C-20 License. The CSLB will review your application and consider factors such as the nature and severity of the crimes, the length of time since the convictions, and any evidence of rehabilitation you will submit.

  1. Get a surety bond

After passing the exams, you’ll be required to get a contractor’s surety bond of $15,000. The bond protects your clients from contractor damage caused by poor workmanship and license violations. It is also used for the benefit of unpaid employees. The CSLB provides a Contractor’s Bond form (Form 35), which must be written and approved by a licensed surety company.

How much does it cost to get a C-20 license? 

The C-20 HVAC License costs between $799 and $949 in total, but fees may vary. 

The original application fee for the entrance exam (one classification) is $450. You must pay an initial license activation fee of $200 if you are a sole owner and $350 if you are a non-sole owner after passing the examination. Furthermore, the $15,000 surety bond may cost you around $100. You must also pay miscellaneous fees, such as the $32 live scan fingerprinting fee and the $17 Federal Bureau of Investigation Processing fee.

If you retake the exam, you must pay an additional $100 fee, which does not increase regardless of how many times you retake the exam. 

How long does it take to get a C-20 license?

After passing the examination, it will take 15 to 90 days to get your C-20 license. However, take note that the month you begin affects the application processing time. If you already have four years of Journeyman experience, the application processing time is usually six to eight weeks. Following approval, you must wait three to four weeks for the examination. 

In some cases, your application may be delayed due to factors such as the time of year you applied, your criminal history, errors on your application, or gaps in proving your experience.

Resources for Getting a C-20 License

Most applicants prepare for the exam through classes, online programs, and review centers, knowing that it covers a wide range of topics. If you don’t have time to attend review centers or contractor license schools, you might prefer to enroll in online programs instead. 

Live and recorded online classes, online law, and business reviews, and test-taking skills seminars are all available through online programs. You should also select programs that offer a variety of learning resources, such as audiobooks, DVDs, textbooks, and other review materials. 

The CSLB also provides a study guide with recommended study resources to help you prepare for exams.

Getting the C-20 License can be a huge step forward in your career if you want to start your own business or work with larger clients! Whether you are new to the HVAC Trade or have some experience, there are options you can take to get licensed. You can begin by working in a company that offers apprenticeship or certification programs. The key to a smooth application process is to have the necessary experience, correct information, and prepare for examinations. 

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