Make sure it’s not an operator error
Before you go dialing 311 about the uninhabitable conditions, make sure the valve on your radiator isn’t shut all the way off. Doing so can make hot steam accumulate, cause leaks, and destroy your radiator. If you didn’t already have water hammer, you’ll definitely have it now. Many renters mistake the knob for a temperature-control valve, but it’s really just open or closed. Having a partially opened valve will ensure you’re woken by a cacophony of clanging.
Cover up your radiator
A steam heat expert, Dan Holohan, told City Lab that radiators only ever reach about 215 degrees, meaning it’s safe to cover them with a sheet, towel, or blanket to keep heat from escaping. Just avoid synthetics (think: polyester) which can melt.