DENVER GUIDE

What to do on a Denver night when the heat stops

The house is sliding colder, the furnace has stopped answering, and the overnight forecast is a hard drop. No heat is a sorting problem before it is a shopping problem. Some conditions mean leave the building. Some mean a careful wait until morning. The equipment and the people in the rooms decide which.

By Mike Maziarz · Sources checked October 6, 2026 · How we write these guides

Leave first if the air is wrong

Smell gas and the heating plan is over. Get everyone out. Do not flip switches on the way, including the thermostat and the furnace disconnect. From outside, call the emergency number printed on the gas bill. Many of those bills say Xcel Energy. Do not re-enter to grab a coat from the closet if the odor is strong. A heating company cannot clear a leak for you.

A carbon monoxide alarm, or a headache, dizziness, or flu-like illness that eases when people step outside, is the same kind of exit. Get everyone out and call emergency services. Do not open windows and keep searching the basement for the source. Do not silence the alarm and go back to sleep. Fuel-burning heat stays off until a qualified person says otherwise.

Those two exits outrank a cold bedroom. You can be uncomfortable and safe. You cannot be comfortable and standing in gas or in combustion products. If you are unsure which alarm you heard, treat it as real and sort the device from the sidewalk.

Who is in the house

After the air is safe, look at the people. An infant, an older adult, someone who cannot move well, or anyone who gets sick easily in the cold changes a 'wait until morning' into a tonight problem. A healthy adult in a house that is merely chilly, with blankets and a safe electric heater, is a different scene from a house that is still falling and already hard to be in.

Pipes on an outside wall, in a crawl space, or in a cabinet on an exterior Five Points or Capitol Hill wall can freeze when heat is off and the night is sharp. You will not get a freeze-proof temperature from this page. Open sink cabinets on outside walls if you can do it without leaving a gas odor behind, and let faucets drip only if the pipes are the worry and the water is still running. A burst pipe is a later problem. Gas is the earlier one.

Know where you would go if the house cannot be held tonight: a neighbor, a relative, or a public place that stays open. Ready.gov is the general preparedness frame. This guide will not invent a shelter address. Check the city and the weather before you need the door.

What the equipment is actually doing

A thermostat with a blank screen, a schedule stuck in a deep setback, or a mode left on cool will imitate no heat. Read the screen before you condemn the furnace. Batteries, a tripped breaker you reset once, and a service switch on the cabinet are the hallway checks. The thermostat troubleshooting page is the longer version. Stop if a second breaker trip or a gas smell shows up.

An outdoor unit that is only an air conditioner will not heat the house, no matter how long the fan turns. If heat has always come from a furnace or a boiler indoors, the silent condenser is not the emergency. The air conditioner not cooling notes belong to the hot months. Tonight, find the appliance that is supposed to make heat and describe whether it is silent, clicking, or running with cold supply air.

A heat pump may be defrosting, running a long time, or waiting on backup heat. Vapor off the outdoor coil on a cold night is often that cycle. Silence, plus a house that keeps falling, is not. Do not pour water on the coil in the dark. Do not switch modes at random until something feels hotter.

Do not 'fix' a heat pump with a can

If the only heat is a heat pump and it runs without keeping up, a refrigerant can is not the overnight repair. You cannot see the charge from the yard, and you must not add refrigerant. The refrigerant basics page explains the boundary. On this night the boundary is simpler: leave the ports alone, leave the panels on, and describe the runtime and the rooms.

Backup heat that will not come on is a control or equipment fault, not a dare to jumper a board. Electric strips and a gas furnace used as backup fail in different ways. If the backup is gas and you smell gas, you are back at the exit. If it is electric and a breaker will not stay on, leave the breaker off.

Ice on a heat pump coil in a snowstorm is a visibility note. Clear loose snow from around the cabinet if you can do it from the ground without climbing. Do not chip the coil. A buried fan is a reason to stop the outdoor unit if the manufacturer switch is one you already know, and to tell the technician the fan was packed in snow.

Temporary heat that does not create a second emergency

A portable electric heater listed for indoor use, plugged straight into a wall receptacle, kept away from bedding and curtains, is a bridge. Do not run it from a thin extension cord coiled under a rug. Do not leave it pointed at the furnace closet while you sleep. One heater is a bridge. A daisy chain of heaters on one circuit is how breakers trip and cords overheat.

Do not heat the house with a gas oven, a grill, a camp stove, or a generator in the garage or the kitchen. Those are carbon monoxide machines in a closed volume. An attached garage with a car running is the same mistake. If you are cold enough to consider them, you are cold enough to leave for a safer building.

Close rooms you do not need, open the doors of rooms you are trying to hold, and keep supply and return paths clear. That is redistribution, not a repair. It will not save a house with no heat source through a long hard night. Decide earlier than the coldest hour whether people should go.

What can honestly wait until morning

A noisy inducer, a filter you meant to change, or a heat pump that holds temperature with a long run can wait for a planned visit. Waiting is allowed when the building is safe, people can stay warm enough, and the temperature is not still falling out from under you. Say that plainly to the company so they do not treat a comfort call as a gas leak, or a gas leak as a comfort call.

After heat is back, the habit that prevents the next first snow is on the seasonal maintenance page: test heat before you need it, keep the outdoor cabinet clear, and know where the filter is. Do not turn the emergency into a lecture while the house is still cold. Use the page later.

When you do call, give the order of events, who is home, whether gas or an alarm was involved, and what temporary heat you are using. Ask them to repeat what they will and will not do tonight. A replacement pitch in the alley can wait. A technician who will name the stopped step in the sequence is the visit you wanted.