No Heat at Night: Safe Steps Until Help Arrives

It is 2 a.m., the house feels colder than it should, and the furnace is silent. In a Chicago winter, a heating failure overnight can turn uncomfortable quickly and dangerous if temperatures keep dropping. The most important things are to stay calm, check for simple fixes, keep everyone warm safely and protect your home until help arrives.

This guide gives you a step-by-step plan. If you smell gas, leave the building and call Peoples Gas at 866-556-6002 from outside. If a carbon monoxide alarm sounds, get everyone out and call 911.

Step 1: Make Sure It Is Safe

• Gas smell? Leave immediately and call from outside. See our guide on what to do if you smell gas.
• CO alarm? Get everyone out and call 911.
• Smoke or burning smell? Turn off the equipment if safe and call 911 if there is smoke or fire.
• Water near electrical equipment? Turn off power to the equipment if you can do so safely.

Step 2: Quick Checks That Often Restore Heat

Thermostat

Make sure it is set to Heat and several degrees above the current temperature. Replace batteries if the display is blank or dim. Check that a schedule did not lower the setting.

Power

Check the furnace or boiler service switch, which looks like a light switch, and the breaker in your electrical panel. Reset a tripped breaker once. If it trips again, leave it off.

Filter

A clogged filter can overheat a furnace and trip a safety switch. Replace it if it is dirty.

Outdoor Vent Pipes

If your furnace vents through white PVC pipes on the side of the house, check that snow or ice has not blocked them after a storm. Clear them gently by hand.

Error Codes

Look for a blinking light or display on the furnace or boiler. Write down the code before resetting.

Boiler Water and Pressure

For hot water boilers, check the pressure gauge. For steam boilers, check the sight glass water level. If a steam boiler is hot with no water visible, turn it off and do not add water.

One Reset

Turn the thermostat off, switch the furnace or boiler off for about 30 seconds, then turn it back on and set the thermostat to heat. If it starts and runs, monitor it. If it locks out again, stop and call. Our guides on furnace won't turn on and boiler on but no heat go into more detail.

Step 3: Call for Emergency Service

If the quick checks do not work, call for emergency HVAC service. Tell them your system type, what is happening, any error codes, the current indoor temperature and whether vulnerable people are in the home. If you rent, also notify your landlord or building manager right away.

Step 4: Keep Everyone Warm Safely

• Pick one room. Gather in a smaller interior room, ideally one with fewer windows and on a lower floor, and close the door.
• Block drafts. Close curtains and blinds. Roll towels against door bottoms.
• Dress in layers. Hats, socks and layers help retain body heat. Use sleeping bags and blankets.
• Use body heat. People and pets together in one room keep it warmer.
• Eat and drink. Warm drinks and food help the body produce heat. Avoid alcohol, which can make you feel warm while actually increasing heat loss.

Step 5: Use Only Safe Heat Sources

If you use an electric space heater:

• Choose a modern heater with tip-over and overheat shutoff.
• Plug it directly into a wall outlet, not an extension cord or power strip.
• Keep it at least three feet from beds, curtains, furniture and anything that can burn.
• Place it on a hard, level surface.
• Do not leave it running unattended or while everyone is asleep.

Our guide on space heater safety covers more.

Never use these to heat your home: gas ovens or stovetops, charcoal or gas grills, camp stoves, kerosene or propane heaters not designed for indoor use, or generators. They can produce deadly carbon monoxide or start fires. Run generators only outdoors, far from windows and doors.

Step 6: Protect Your Pipes

• Open cabinet doors under kitchen and bathroom sinks, especially on exterior walls.
• Let cold and hot faucets on exterior walls drip slightly.
• Keep interior doors open to plumbing areas if you can do so without cooling the room where people are staying.
• Know where your main water shutoff is in case a pipe bursts.

In boiler-heated homes, radiator pipes in cold areas can also freeze if heat is out for a long time. Mention this when you call for service.

Step 7: Know When to Leave

• The indoor temperature keeps falling toward unsafe levels.
• Infants, older adults or people with health conditions are at risk.
• You cannot heat a room safely.
• Service cannot arrive for many hours during extreme cold.

Go to a friend's or family member's home, a hotel or a warming center. In Chicago, call 311 for information on warming centers. Take medications, phone chargers and pets with you.

Watch for Signs of Cold Stress

Signs of hypothermia include shivering, confusion, slurred speech, drowsiness and very cold skin. Older adults and infants may not shiver. If you suspect hypothermia, call 911. Warm the person gradually with blankets and dry clothing.

For Renters

In Chicago, landlords are required to provide heat during the heat season, from September 15 to June 1. Notify your landlord immediately. If heat is not restored, you can report it through 311. See our guide on Chicago heat rules for landlords and tenants.

After the Heat Is Back

• Check pipes for leaks as they thaw.
• Ask the technician what failed and whether other parts are at risk.
• Replace the filter if it was dirty.
• Schedule a full tune-up if the system has not been serviced recently.
• If your system is old and failing, start planning replacement before the next cold snap. Our guide on furnace lifespan can help.

Prevent the Next Overnight Failure

Annual fall service, regular filter changes and keeping vents clear prevent many overnight no-heat calls. See our winter protection guide.

Help for Older Adults Living Alone

Older adults living alone are especially vulnerable when the heat fails, because they may not notice the temperature dropping or may be reluctant to ask for help. If you have an older relative or neighbor, make a plan with them before winter: who they will call, where the spare blankets are, which room they will use and whether they can stay with someone during a long outage. During extreme cold, check on them in person or by phone at least once a day.

Using Your Car Safely

If you go out to your car to warm up or charge a phone, never run the engine in an attached or detached garage, even with the door open. Carbon monoxide can build up quickly and seep into the home. If the car is parked outdoors, make sure the tailpipe is not blocked by snow before running the engine.

Food, Water and Medications

A heat outage often comes with other disruptions. Keep drinking water, easy-to-prepare food, needed medications and a flashlight with fresh batteries accessible. If you lose power as well as heat, keep the refrigerator and freezer closed to preserve food, and plan for any medical devices that need electricity.

What to Expect When the Technician Arrives

An emergency technician will usually confirm the problem, check safety first, then diagnose the failure. Common overnight fixes include replacing ignitors, flame sensors, capacitors, pressure switches, condensate traps and circulator pumps. If a part is not available immediately, the technician may be able to provide a temporary solution or explain when the repair can be completed. Ask for the diagnosis and options in writing so you can make an informed decision, especially if replacement is suggested.

Steam and Hot Water Systems at Night

If your home has a boiler, there are a few extra checks. On a hot water system, look at the pressure gauge. If it has dropped very low, the boiler may have shut down on a low pressure or low water safety. On a steam system, look at the sight glass. If the water level is low but visible, and you know how to add water through the feed valve, you may be able to restore heat. If the boiler is hot and no water is visible at all, turn it off and do not add water. Call for service. Our guide on steam vs. hot water boilers explains how to tell which you have.

Heat Pumps at Night

If your home uses a heat pump and it stops heating, check whether the outdoor unit is buried in snow or encased in ice. If so, switch the thermostat to emergency heat, if available, so the backup heat source takes over, and call for service. Do not chip ice off the coil. Our guide on heat pump defrost explains what is normal.

A Short Checklist to Print

• Safe? No gas smell, no CO alarm, no smoke.
• Thermostat on Heat with power.
• Furnace or boiler switch and breaker on.
• Filter clean.
• Outdoor vents clear.
• Error code written down.
• One reset tried.
• Called for service.
• Everyone in one warm room, safe heat only.
• Cabinet doors open, faucets dripping.

Do Not Ignore Warning Signs Before the Failure

Many overnight failures give warning signs days or weeks earlier: short cycling, unusual noises, a furnace that takes several tries to light, a boiler that needs frequent water, or rooms that are slower to warm. If you notice these, schedule service during regular hours before the system quits on a frigid night.

Need Heat Now?

If everyone is safe and you need emergency heating service, call (312) 638-0812. We serve neighborhoods including Lakeview, Portage Park and Rogers Park.