Landlord Won’t Fix Broken Heater in Winter — Habitability Rights?

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Illustrative scenario prepared by my practice.
For informational purposes only. This is not legal advice.
Hypothetical question

Looking for advice on this situation. Landlord Wont Fix Broken Heater in Winter - Habitability Rights? What are my options here?

Details: I'm in a situation where I need to understand my legal options. Has anyone dealt with something similar?