Section 14. Any lessor or landlord of any building or part thereof occupied for dwelling purposes, other than a room or rooms in a hotel, but including a manufactured home or land therefor, who is required by law or by the express or implied terms of any contract or lease or tenancy at will to furnish water, hot water, heat, light, power, gas, elevator service, telephone service, janitor service or refrigeration service to any occupant of such building or part thereof, who willfully or intentionally fails to furnish such water, hot water, heat, light, power, gas, elevator service, telephone service, janitor service or refrigeration service at any time when the same is necessary to the proper or customary use of such building or part thereof, or any lessor or landlord who directly or indirectly interferes with the furnishing by another of such utilities or services, or who transfers the responsibility for payment for any utility services to the occupant without his knowledge or consent, or any lessor or landlord who directly or indirectly interferes with the quiet enjoyment of any residential premises by the occupant, or who attempts to regain possession of such premises by force without benefit of judicial process, shall be punished by a fine of not less than twenty-five dollars nor more than three hundred dollars, or by imprisonment for not more than six months. Any person who commits any act in violation of this section shall also be liable for actual and consequential damages or three month's rent, whichever is greater, and the costs of the action, including a reasonable attorney's fee, all of which may be applied in setoff to or in recoupment against any claim for rent owed or owing. The superior and district courts shall have jurisdiction in equity to restrain violations of this section. The provisions of section eighteen of chapter one hundred and eighty-six and section two A of chapter two hundred and thirty-nine shall apply to any act taken as a reprisal against any person for reporting or proceeding against violations of this section. Any waiver of this provision in any lease or other rental agreement, except with respect to any restriction on the provision of a service specified in this section imposed by the United States or any agency thereof or the commonwealth or any agency or political subdivision thereof and not resulting from the acts or omissions of the landlord or lessor, and except for interruptions of any specified service during the time required to perform necessary repairs to apparatus necessary for the delivery of said service or interruptions resulting from natural causes beyond the control of the lessor or landlord, shall be void and unenforceable.