N.Y.C. Admin. Code § 27-2028: § 27-2028 Central heat or electric or gas heating system; when required.

Except as otherwise provided in this article, every multiple dwelling and every tenant-occupied one or two-family dwelling shall be provided with heat from a central heating system constructed in accordance with the provisions of the building code and the regulations of the department. A system of gas or electric heating provided for each dwelling unit may, if approved by the department, be utilized in lieu of a central heating system if:

(1) the system is lawfully in use on July fourteenth, nineteen hundred sixty-seven; or

(2) the system is approved by the appropriate city agencies having jurisdiction and is installed in a structure or building erected, converted, substantially rehabilitated, or completely vacated, after July fourteenth, nineteen hundred sixty-seven.