When the heat runs but the home stays cold
A heater that runs but cannot warm the home to a reasonable temperature can be a habitability problem, because the law requires heating facilities that actually work — not just a system that turns on.
If your heater struggles to keep the unit livably warm, the cause may be an undersized, failing, or poorly maintained system, or a problem like leaking ductwork — issues the landlord is responsible for addressing. Report how the heat actually performs, not just that it exists.
Telling your landlord "the heater runs but the apartment stays cold" is more useful than "the heat works," because it describes the real problem. A consistent inability to warm the home, especially in cold weather, can cross the line into a habitability issue. If your heat cannot keep your home warm and your landlord dismisses it, a free review can help you understand your options.
This is general information about California tenant rights, not legal advice. Every situation is different.