Conn. Agencies Regs. § 25-129-7
Registration as a limited geothermal contractor W-7 permits the registrant to construct a geothermal bore hole or geothermal system, as defined in section 25-128-36(c) of the Regulations of Connecticut State Agencies, up to and including the manifold connection, including, but not limited to, the installation, repair, and maintenance of piping, casing, heat transfer media, pumps, pump motors, and valves, but excluding direct exchange systems, as defined in section 25-128-36(c) of the Regulations of Connecticut State Agencies. Before any registration is issued to any individual, the Board shall require that the applicant submit documentation that the applicant has been actively engaged in the geothermal bore hole drilling trade as a geothermal driller for a period of twenty-four (24) months prior to the date of application or has held a valid W-8 registration for at least two years. The applicant shall evidence that he or she has passed a written examination conducted pursuant to sections 21a-7(a)(1) and 21a-8(a)(5) of the Connecticut General Statutes.
Conn. Agencies Regs. § 25-129-7