During the Day: It's safe to leave your heater on for 6-8 hours if you're in the room.
Recommended Usage Times. 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.
You Should Not Leave Space Heaters on Unattended
We do not recommend using space heaters at all because of this risk, but you definitely should not use them at night. If your home is too cold at night, you may want to consider adjusting your thermostat to better meet your needs.
Using the heater too often could lead to undesirable consequences like leaving out skin or nasal passages dried out. It Can Cause Carbon Monoxide Poisoning-It's important to keep your space heater in good working order so you don't have any accidents or health problems.
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).
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.
Oil filled radiator space heaters are some of the safest on the market. 1500W is all the juice an outlet will provide (Roughly 5,000 btus).
Space heaters can take anywhere from 750 watts to 3,000 watts to operate. Large space heaters take immense amounts of energy to run. However, those are most likely used only in commercial and industrial settings. The average residential space heater has two main heat settings, low and high.
Space Heater Recalls
Industrial recalls 8,500 electric garage heaters due to the potential of the heating element overheating and causing a fire hazard. Dyson recalled 338,000 bladeless portable heaters in the U.S. and 43,000 in Canada due to a potential short that could cause the unit to overheat and cause a fire.
According to the Consumer Product Safety Commission, space heaters are involved in more than a thousand home fires every year.
Overusing the heater or using an oversized heater can result in elevated levels of carbon monoxide or nitrogen dioxide fumes in the air. These fumes can cause cold or flu-like symptoms, headaches, and eye, nose and throat irritation.
Using a space heater can be a good way to boost the temperature in a small, drafty room—and it could be less expensive than cranking up your central heating system. But a space heater is economical only if you use it judiciously.
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.
Don't leave your space heater alone.
You might just be going to the kitchen to get a quick snack, yet while you're gone, the unit could overheat, tip or short-circuit. The risk is small, but it's still a risk not worth taking.
Never leave a space heater running when you're asleep or when you leave the area. Locate the heater at least three feet away from bedding, furniture and drapes, or where towels or other fabrics could fall on it and start a fire.
Never Leave Unattended: Do not leave the space heater unattended while it is operating overnight. It is important to be present and aware of any potential hazards that may arise. Always turn off the heater before leaving the room or going to sleep.
Avoid leaving a space heater unattended -- especially for long periods. Do not plug space heaters into extension cords or power strips.
Con: Fire and Burn Risk
The National Fire Protection Association warns that space heaters account for more than 40% of all home heating-related fires. Space heaters are also responsible for most fire-related deaths during winter, and they account for thousands of burn-related injuries each year.
Far Infrared Heaters are the most efficient of all the space heater options and consume the lowest wattage, making them the cheapest to run. Far Infrared is radiant heating and is most easily absorbed by people's skin. In fact, all objects, including us emit and absorb infrared.
Safer Operation
Ductless mini-split systems are generally safer than space heaters. First, they don't get hot to the touch, reducing the risk of the unit burning anyone. Because it is transferring air or using a heat strip, there is little danger in any way.
Absolutely. The US Department of Energy records about 25,000 house fires every year that are linked to a space heater fire.
Make sure your smoke and carbon monoxide detectors are in good working condition before using a space heater. Place the heater out of high-traffic areas and on a level, hard, non-flammable floor surface—NOT on carpets, furniture, or countertops. Never use them to thaw pipes, cook food, or dry clothing or towels.