The failure to furnish heat as required by this subchapter shall not constitute an offense where it is due to a breakdown of the heating plant, if diligence is used to have the plant repaired, unless the breakdown has been caused by the violation of an existing provision of this code or other ordinance of the village relating to the operation of heating plants, nor where it is due to strikes, a general shortage of fuel or any act of the tenant who makes the complaint, or to any cause beyond the control of the person owning or controlling the dwelling, unless written notice of the failure to furnish the heat hereby required is first given to the owner or person in control of the dwelling, or his or her agent, by registered mail, and the temperature readings hereinafter provided for are made after the delivery of the registered letter to the addresses thereof.
(1959 Code, § 16-37)