Section 27-2029. Minimum temperature to be maintained

a. During the period
  from October first through May thirty-first, centrally-supplied heat, in
  any dwelling in which such heat is required to  be  provided,  shall  be
  furnished  so  as to maintain, in every portion of such dwelling used or
  occupied for living purposes:
    (1) between the hours of six a. m. and ten p. m., a temperature of  at
  least  sixty-eight  degrees  Fahrenheit whenever the outside temperature
  falls below fifty-five degrees; and
    (2) between the hours of ten p. m. and six a. m., a temperature of  at
  least  fifty-five  degrees  Fahrenheit  whenever the outside temperature
  falls below forty degrees.
    b. During the period from October first through May thirty-first,  all
  central  heating systems required under this article shall be maintained
  free of any device which shall cause or which is capable of  causing  an
  otherwise  operable  central  heating  system  to  become  incapable  of
  providing the minimum requirements of heat or hot water as  required  by
  this article for any period of time. This subdivision shall not apply to
  any  safety  device  required  by law, or by a rule or regulation of any
  city agency, to be used in conjunction with a central heating system.