How to Use a Space Heater Safely: Space Heater Basics

If you’ve ever worked in a chilly office or wanted to warm up in your bedroom or living room, you have probably thought about using a space heater. Space heaters are convenient, but they do present serious safety risks and fire hazards — especially when they aren’t used properly.

The National Fire Protection Association reports that space heaters cause 40 percent of house fires that involve heating equipment. They also account for 84 percent of deaths in heating-related fires.

These are scary statistics, so it’s important to use your space heater safely. They are only meant for short-term use, and you should never leave them on when you are sleeping.

Whether you are looking at electric heaters or combustion models, here is everything you need to know about choosing the right space heater and how to stay safe while using them.

What are the Main Types of Space Heaters

At a basic level, there are two categories of space heaters:

• Electric space heaters
• Combustion space heaters

Electric space heaters are typically the least expensive and easiest to find. Combustion space heaters are usually more effective, but they are also more expensive and require proper ventilation.

Electric room heaters

Ideal for small spaces or warming up a specific area—under your desk, for example, or a corner of the garage—electric heaters work quickly and are easy to use.

Fan heaters use a small fan to blow air over coils of heated wire. Most newer models are equipped with safety features such as cool-touch grilles and auto-shutoff sensors if the heater is knocked over, but it’s still important to keep the unit away from fabrics, paper, and any other combustible materials.

Ceramic space heaters also use a small fan, but they work slightly differently than a traditional fan heater. In a ceramic heater, heat is created by an electric current heating up metal filaments embedded in the ceramic plates.

Radiator-style space heaters look a lot like the accordion-style radiators sometimes found in older homes and apartments. Radiator space heaters are filled with oil; when they’re plugged in, the electrical current gradually heats the oil. This style of space heater is quiet and radiates heat even after the unit has been turned off.

Combustion space heaters

If you’re looking for an energy-efficient space heater, you may need to look for a fuel-powered heater (also called a combustion space heater). Natural gas and propane are the most common fuels used in combustion space heaters. Combustion heaters are labeled as either vented or unvented, depending on their construction.

Vented space heaters are intended to be a permanent addition to your home. In most cases, they’re installed on an outside wall with the flue (or vent) routed through the wall or roof. Look for a heater that will connect directly to a gas line to avoid having to manually fill a fuel reservoir.

Unvented space heaters are easier to install than vented heaters, and they tend to be a little less expensive. The primary danger of an unvented space heater is the risk of carbon monoxide buildup in the home.

Carbon monoxide (CO) gas is a poisonous—and potentially fatal—byproduct of inefficient combustion, so it is vital that you inspect and clean your unvented heater annually to ensure that it’s working properly. Install a carbon monoxide detector (and change the batteries twice per year) in your home if you use an unvented space heater.

Chronic headaches, nausea, sore throat, and a stuffy room are all signs of an inefficient, improperly installed, or malfunctioning heater that is releasing poisonous emissions into the house. If you or any of your household members complain of these symptoms, turn off the heater immediately and open windows for ventilation.

How to Use a Space Heater Safety

Space heaters are not intended to heat your entire home. If your heating system can’t heat your home adequately, contact an HVAC company first. But if you need a little more heat in a specific place from time to time, a space heater can be a perfect solution.

That being said, space heaters create a lot of heat, and electric versions use a lot of power; under the right conditions, this can cause a fire. If you’re going to use a space heater, follow these important safety tips:

1. Never leave a space heater unattended.

Never leave a space heater running when you are not in the room. If you leave the room for any reason, switch the heater off. Even if you will only be gone for a few minutes, there is always a risk of an accident.

Also, you should always turn off and unplug the space heart when you level the room. Leaving it plugged in can lead to short circuits, power surges, or overheating.

Also, never leave children or pets unattended around a space heater. They can injure themselves or even start a fire.

2. Never leave a space heater running overnight.

Space heaters are only meant to run for a few hours, and you should never leave one running overnight. The risk of it falling over, shorting out, or catching your room on fire are just too great.

Relying on space heaters to heat your entire home is extremely dangerous. Instead, call a local HVAC company for an energy audit and a long-term solution.

3. Keep space heaters away from flammable items.

You should always keep space heaters at least 3 feet away from anything flammable in the room. Putting them too close to curtains, linens, upholstery, or paper goods can cause a fire.

Flammable items include curtains, upholstered furniture, other textiles, paper, books, and anything else that could burn when overheated.

Before buying a space heater, think about where you will place it. Make sure you have enough room to operate it safely.

4. Place your space heater on a flat, stable surface.

You should always place your space heater on a firm and level surface. Never place a space heater on carpet, bedding, furniture, or any other uneven or unstable surface.

It is best to put it on a heat-resistant surface like tile or brick. Keep it in an area that gets minimal foot traffic to prevent accidents.

Also, look for models that automatically turn off if they get tipped over. You should test this feature every month to make sure that it continues to work properly.

5. Do not plug a space heater into an extension cord.

Electric space heaters pull a lot of power, so you should always plug them directly into a wall outlet.

Extension cords and power strips are not designed to handle the constant power needs of a space heater. This can cause the cord or strip to overheat or even start a fire.

6. Inspect your space heater before each use.

Just like any other household appliance, space heaters have a finite lifespan. Heavy use, improper off-season storage, and normal wear and tear can all cause damage to the heater and its cord (if it’s electric).

Carefully inspect the heater before each use. Don’t use the heater if:

• The cord is damaged or fraying
• The ceramic panels are cracked or broken
• The heater or the outlet sparks or smells odd
• The flame pops or flares too high on a combustion heater

Some space heaters are more expensive than others but do not try to save money by using a damaged heater. Your life is far more valuable.

How To Choose a Space Heater

You should only purchase a space heater certified by the Underwriter’s Laboratory (UL). If you are using the space heater inside, an electric model is your best option. They are safe and reliable to use inside. Choose one with a ground fault circuit interrupter plug, automatic shut-off, and at least a 6-foot cord.

Combustion space heaters that burn kerosene, natural gas, propane, or wood pellets to produce heat. However, they also produce carbon dioxide. If you are using them indoors, you need the proper ventilation and ductwork. Otherwise, only use them outside.

Space heaters can give off anywhere from 10,000 to 40,000 BTU per hour, depending on the design. For the best value, choose the right amount of BTUs for the pace you want to heat. Running an oversized heater or running a space heater at high power for long periods of time can increase the risk of a fire.

Common Alternatives to Space Heaters

Looking for an alternative to a space heater? While space heaters are convenient, you do have options. Here are a few other options to consider, most of which come down to conserving energy. Let’s take a look.

1. Put on a sweater.

I promise I’m not trying to mother you, but if you’re cold, bundle up a bit before plugging in a space heater or turning up the thermostat. (At my house, we’re big fans of wool socks and base layers—you can find them online and at any sporting goods store.)

You’ll conserve energy by insulating yourself first rather than turning immediately to your HVAC system—this is good for both your bank account and the planet.

2. Close any gaps or cracks in window and door frames.

If you can stand in front of a window or door and feel a draft, the weather stripping likely needs to be replaced. Older wood window frames are notorious for cracking and deteriorating if they aren’t properly maintained; fill any openings—even if they’re small—with caulk.

By sealing your windows and doors, you’ll ease the burden on your HVAC system, lower your utility bills, and make your home less welcoming to critters seeking shelter from the cold.

3. Open curtains and shades during the day, and close them at night.

Take advantage of the sun’s natural heat energy to warm your home. Leave your window treatments open during the day to allow sunlight into the room, and then close the curtains in the evening to trap the warmth for a while as the sun goes down. This trick works best with thick, heavy curtains and single-pane windows.

4. Cover single-pane windows with thermal window film.

Glass is not a good insulator, so single-pane windows can be the reason your house is chilly in the winter and hot in the summer. But replacing windows is an expensive proposition, especially if you spring for high-quality double- or triple-pane versions. If window replacement just isn’t in the budget this year, install thermal window film instead.

Leave your thermal window film on year-round for maximum energy savings. The film will help keep warm air in the house during the winter and cooled air inside during the summer, and with the newer styles of thermal film, you won’t have to sacrifice a clear view outside.

The Bottom Line

Keeping your home comfortable can be difficult, especially in the winter. While space heaters are a great way to improve your comfort, they are only meant for short-term use. If you are using a space heater, follow all safety precautions and always keep children and pets away from it.

But if you are consistently relying on a space heater to stay warm, you should talk with a local HVAC company about addressing your heating issues. Your current heating system may be inefficient or undersized. A new heating system can resolve your heating problem. Plus, it is usually much more cost-efficient than running a space heater around the clock.