The period between October 1 and May 31 is designated as Heat Season. During this time, the City requires building owners to provide tenants with heat according to the following rules:

• Between the hours of 6:00 AM and 10:00 PM, if the outside temperature falls below 55 degrees, the inside temperature must be at least 68 degrees Fahrenheit.
  
  
• Between the hours of 10:00 PM and 6:00 AM, if the temperature outside falls below 40 degrees, the inside temperature must be at least 55 degrees Fahrenheit.
  

During Heat Season, the City accepts complaints about lack of heat in residential, non-residential, commercial, or New York City Housing Authority (NYCHA) buildings, or in schools.

Before filing a heat complaint, you should try to resolve the issue with your landlord, managing agent, or superintendent.

Tenant Heating & Hot Water Rights:
http://home2.nyc.gov/html/hpd/html/tenants/heat-and-hot-water.shtml

FAQs about Heating Issues:
http://www.nyc.gov/html/hpd/downloads/pdf/PreservationSvcsBrochure_Heat.pdf

Report Maintenance Problems:
http://www.nyc.gov/html/hpd/html/tenants/how_to_report.shtml