During the Day: It's generally safe to run your space heater for 6 to 8 hours during the day while you're home and active.
Electric heaters of any type are unsafe to leave running overnight because they carry a significant amount of risk. If a space heater falls over or becomes too hot from running for too long of a period of time, that can lead to a fast-moving fire that occurs while you are asleep and cannot act fast enough.
The duration for which you can leave a space heater running depends on the time of day and your specific needs. During the Day: It's safe to leave your heater on for 6-8 hours if you're in the room. If you're busy or moving between rooms, consider using a timer to automatically shut it off after a few hours.
Never leave a space heater unattended due to the risk of fire. Even if it's so cold you're afraid your pipes will freeze, you're better off unplugging the heater and leaving the water running (a stream about the size of a pencil lead should keep the pipes from freezing).
It isn't bad to run your heating system on a 24/7 basis if outdoor weather conditions demand indoor warmth. For many households, maintaining a constant indoor temperature is the only way to survive the winter. Just be aware that this is likely to cause additional wear and tear on your heating system.
Overusing room heaters, especially oversized ones, can lead to elevated levels of carbon monoxide and nitrogen dioxide fumes in the air. These invisible intruders can bring about cold or flu-like symptoms, headaches, and irritating sensations in the eyes, nose, and throat.
A furnace that's running non-stop is not necessarily bad. During the coldest days in winter, it is normal for a furnace to run almost constantly to keep the home warm. As long as the furnace is running efficiently and not making strange noises, the constant operation is likely nothing to worry about.
Space heaters usually consume between 400 and 1500 watts of electricity, and the majority use around 800-1000 watts. If an electric heater is used for 3 hours a day, then it could add up to 90 kWh of electricity to your monthly electricity bill, which could be an additional 5-10% of your total monthly electricity cost.
Do the cooler temps have you wondering, “What should I set my heat to?” According to ENERGY STAR, the magic number for your winter thermostat setting is 68 degrees Fahrenheit when you're at home. This temperature strikes a perfect balance between staying comfortable and saving energy.
Fires are one of the biggest risks associated with leaving electric heaters on all night. If an electric heater has frayed wiring or malfunctions, then there is a high chance of it igniting. Electric heaters also make the air in the room really dry by conducting a lot of heat.
On average, you can expect to pay about 20 cents per hour to run a typical space heater that's 1,500 watts and can heat a standard room such as a home office or bedroom. If you run it for eight hours per day, you'll pay about $1.60 per day or $48 per month.
What is the safest heater to leave on overnight? While it's not recommended to leave any space heater on if you're not monitoring it, oil-filled, radiant space heaters are considered safer than ceramic convection (hot air) types, according to Roberson. Both of these options are safer than open-coil heaters.
At Night: If you choose to use your space heater overnight, it's best to limit its operation to 4 to 6 hours on a lower setting. Some people prefer to set their heater to turn off about an hour after they fall asleep, which you can manage through a timer or a model with a scheduling feature.
The constant burning of fuel to heat your home will not only result in energy being used but also lost. In a standard home, heat loss is quite significant compared to the heat you're putting into it through your boilers and radiators.
Turn off your heaters before going to bed and when you're leaving the house. Many appliances continue to draw stand-by power even when switched off. This can account for up to 3% of your total energy costs. Turn off appliances not in use (such as TVs, computers and consoles) at the power point.
Using a space heater 8 hours per day will use about 84 kilowatt-hours of electricity per week. It costs an average of $51.65 to run a space heater for a month and $258.26 to run for a year.
Electric space heaters can be used safely, but they are not the safest option for staying warm when the temperature drops. According to the National Fire Protection Association (NFPA), space heaters account for 43% of home heating fires and 85% of home heating deaths. They can also be a hazard in the workplace.
Old windows and drafty attic spaces with air leaks are common culprits behind unusually high electric bills. Invest in new energy-efficient windows with better seals and glass, and make sure attic and basement spaces have proper insulation. The investment today will save you money on your bill down the road.
It's a Fire Hazard
Leaving your electric heater on all day is also a fire hazard. If you are not home to monitor the heater, it could overheat and start a fire.
The disadvantages of electric heating encompass slower heating times and higher energy bills over time. For instance, an electric furnace can take a significant amount of time to power the included heating element and adequately warm the air within a home.
"Your system's [furnaces] aren't designed to run in temperatures that are below-zero for long periods of times," Marchand said. To help alleviate some of the stress off of systems during these cold temperatures, set your thermostat a few degrees lower than what you're used to.
A dirty air filter can get clogged and reduce air flow through your home's heating system. This means the air your furnace is heating isn't reaching your living spaces and causing your furnace to cycle on more often and work longer while it's on.
Some homeowners naturally worry about the risks of a breakdown if they run the fan all the time, but this will not be a concern for you if your HVAC system was properly installed and maintained. The only possible exception here is a very old fan system, which should generally be replaced in the near future anyways.