The Department of Consumer Protection may suspend or revoke any registration issued under § 16a-23m if the holder of such registration is grossly incompetent, engages in malpractice or unethical conduct or knowingly makes false, misleading or deceptive representations regarding such holder’s work, violates any provision of § 16a-23n or 16a-23v, fails to comply with any subpoena issued pursuant to this section or violates any regulations adopted under § 16a-23q. Before any such registration is suspended or revoked, such holder shall be given notice and opportunity for hearing as provided in regulations adopted by said commissioner in accordance with the provisions of chapter 54. Said commissioner may compel by subpoena, at his or her discretion, the production of any documents from any heating fuel dealer or from any provider of futures or forwards contracts, physical supply contracts or other similar commitments or a surety bond, regarding compliance with the provisions of sections 16a-23m to 16a-23r, inclusive, or § 16a-23v.