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.
The best way to prevent a fire is to never leave a space heater running in a room unattended—that way, if anything does go wrong, you can take action quickly. If you have kids or pets that could knock a heater over or drape fabric on it, keep a very close eye on its operation.
During the Day: It's safe to leave your heater on for 6-8 hours if you're in the room.
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.
Absolutely. The US Department of Energy records about 25,000 house fires every year that are linked to a space heater fire.
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).
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.
Improperly vented (and unvented), blocked, separated, rusted, or corroded small space heaters may emit dangerous levels of carbon monoxide (CO) and other gases into the home, causing sickness and death.
Turn off the space heater when no one is occupying that area or when it is out of sight. Do not use space heaters if small children are in the area. Unplug space heaters at the end of each day and make sure the unit has cooled before exiting the room or jobsite.
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.
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.
Most home heating deaths happened because a space heater was too close to furniture, clothing, mattresses, or bedding. Make sure your heater is at least three feet from anything that can burn.
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.
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.
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.
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.
While electric space heaters do not produce carbon monoxide (CO), non-electric space heaters (propane gas, natural gas, kerosene, wood) can if incomplete combustion occurs. If these types of heaters are in use, it is recommended that a working CO detector be used to indicate the presence of high-level CO gas.
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.
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.
It's More Advisable to Turn the Heat Down, Not Off
If you really want to save money and avoid the problems associated with turning off the heat at night, what you should do instead is just turn it down.
Oil-filled heaters are very less likely to cause you any trouble when you leave them on overnight. These radiators have a high boiling point which helps the internal pressure of the oil stays constant. They don't have any moving parts, so you won't have to face any type of noise and sleep interruption.
Baseboard heaters also warm a room more slowly compared to space heaters. They rely on convection heating to heat the air, which takes time to circulate and warm up the entire space, resulting in a longer wait to reach your ideal indoor temperature.
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.