Is It Safe to Run a Generator During a Winter Power Outage?

Quick answer: Yes, if the generator runs outdoors only, at least 20 feet from doors, windows and vents, and never in a garage, even with the door open. Keep battery-powered CO alarms working inside. Connect to house wiring only through a transfer switch a licensed electrician installs, never a wall outlet.

Where is it safe to run a portable generator?

Outside, well away from the house. The CDC and the Consumer Product Safety Commission, the federal safety agencies, agree on the rules:

• Run it only outdoors, at least 20 feet from doors, windows and vents.
• Never run it inside the house, garage, carport, crawl space or shed, even with fans running or doors open.
• Point the exhaust away from the house and anywhere people might go.
• Set it in a dry spot, protected from rain and ice.

Attached garages are common around Austin, and on a cold, wet night they look like the perfect spot for a generator. They’re also where carbon monoxide builds up and seeps into the house.

Do you need a CO alarm when running a generator?

Yes. Generators make carbon monoxide, which you can’t see or smell. The CDC recommends a battery-powered or battery backup CO alarm in the home whenever you run one, since plug-in alarms go dark with the power. Placement is covered in where CO detectors should go.

If an alarm sounds, get everyone outside first and call 911 from there.

Why can’t you plug a generator into a wall outlet?

It can backfeed, sending power out through your house wiring onto the utility lines. Power companies warn that this can kill lineworkers making repairs and endanger neighbors on the same transformer, and it bypasses some of your home’s own circuit protection. The only safe way to connect a generator to house wiring is a transfer switch, a job for a licensed electrician, usually with a permit.

Can a portable generator run your furnace or heat pump?

A gas furnace, often yes, with the right hookup. A heat pump, usually not. A heat pump’s compressor needs a big surge to start, and its electric heat strips draw far more power than most portable generators can supply.

A gas furnace needs much less, just enough for its blower (the main fan), inducer (a small exhaust fan) and controls. But it’s hardwired, so it has to connect through a transfer switch or a generator inlet (a dedicated plug-in box on the outside wall) an electrician installs. Ask the electrician to check the generator’s size and power quality against what the furnace needs, since some furnace controls won’t light on rough generator power. What to do with your heat pump during a Texas freeze covers the heat pump side.

What other generator safety rules matter in winter?

Fuel, cords and backup heat have rules of their own:

• Shut it off and let it cool before refueling. Never refuel while it runs.
• Store fuel outside living areas in approved containers.
• Use heavy-duty, outdoor-rated extension cords sized for the load, and keep them out from under rugs.
• Never heat the house with a grill, camp stove or gas oven.

When the power returns, give the HVAC system a moment before it starts. See how to restart your system after a power outage. If it won’t heat properly afterward, Gold Eagle’s heating technicians repair furnaces and heat pumps across the Austin area.

What should you do next?

• Put fresh batteries in your CO alarms before winter weather arrives.
• Choose an outdoor generator spot now, at least 20 feet from doors, windows and vents, before you need it.
• Ask a licensed electrician about a transfer switch or generator inlet if you want to run your furnace.
• Schedule a heating check if the system acts up after the power comes back.

Related guides: Where Should CO Detectors Go in a Home With a Gas Furnace?, Why Is Your Carbon Monoxide Alarm Beeping or Chirping? and What Should You Do With Your Heat Pump During and After a Texas Freeze?

About Gold Eagle Services: This guide comes from the team at Gold Eagle Services, a family-run Austin HVAC, indoor air quality and mold remediation company founded in 2017. We’re licensed (TACLA119235 and RCO1783), insured and bonded, and we serve homes across the greater Austin area.

Need help with this in your home? Learn about our heater repair and tune-ups, or call 512-489-4653 to schedule a visit.