What to Do When the Heat Goes Out on a Freezing Night

Losing heat on a freezing night is stressful, especially in an older house with pipes along outside walls. A few calm steps can protect the house and sometimes get the heat back on.

Safety first

If you smell gas, leave the house right away and call the gas utility from outside. Do not flip switches or use the thermostat. If a carbon monoxide alarm is sounding, get everyone outside and call 911.

Quick checks

• Make sure the thermostat is set to heat, above room temperature, with fresh batteries.
• Check the emergency switch for the boiler or furnace, often at the top of the basement stairs.
• Look for a tripped breaker on the heating circuit.
• On oil heat, check the tank gauge; an empty tank is a common cause.
• On high-efficiency furnaces, check outdoor vent pipes for snow.

If the burner has locked out, you may reset it once. If it locks out again, stop and call; repeated resets can cause damage, and on oil systems can flood the chamber.

Protect the pipes

Open cabinet doors under sinks on outside walls so warm room air reaches the pipes. Let faucets on outside walls drip slightly. Close off unused rooms and keep doors to the basement open if the boiler room is warmer.

Stay warm safely

Use space heaters only if they are in good condition, plugged directly into the wall and kept away from anything that can burn. Never use an oven, grill or generator indoors for heat.

When you call, tell us the type of system, what you checked and whether anyone in the home is elderly, very young or unwell. That helps us set priority and come prepared.