How to Select the Best Space Heater

Indoor electric space heaters are designed to bring thermal comfort to your indoor space, whether your space is a corner of your home, an office, or a warehouse. But each of those spaces requires a different approach to heating. With so many applications and consumer preferences, it’s no wonder the marketplace offers so many types of indoor electric space heaters. 

This guide provides helpful information for sorting through the pros and cons, and arriving at a knowledgeable decision in regard to the right space heater for your needs. Factors to consider include:

• How much space it must heat
• Amps, volts, wattage and BTU’s
• Optional features
• Safety

Consideration 1: the Amount of Space to Be Heated

First, consider whether you wish to provide supplemental heat, or whether your electric space heater will be the sole source of heat for your space. Supplemental heat to a corner of your living room, for example, will require a lower power space heater than a room which has no other heat source. Space heaters can be efficient in some applications and inefficient in others. For example, if you are occupying one or two rooms of a house and don’t want to heat the entire house, a space heater or two can cost less to operate than a furnace at the center of a whole-house heating system.

Large and medium-sized spaces - a forced air design is available in all sizes and types of space heaters, from the smallest home units to the largest industrial units, but they are particularly effective in heating spaces in excess of 150 sq. ft. The term “forced air,” as it applies to space heaters, simply means the space heater design incorporates a built-in fan that blows air across the heated media to circulate the heat quickly throughout the space. 

As with all designs of space heaters, the benefits of forced air units come with some trade-offs: 

• The heat stops almost as soon as the electrical current to the elements stops.
• Consideration has to be given to the positioning of the space heater and where its fan is blowing the hot air. People, animals, and materials should not be in the path of the hot, forced current. 
• The fan motor on a forced-air space heater adds to the unit’s overall power consumption, generates noise, and functions separately from the heating components so, if the fan motor breaks, it makes the space heater ineffective.

Small spaces - while forced air space heating units can certainly be used in smaller spaces, radiant space heaters may be a better option for spaces under 150 sq. ft. 

Radiant space heaters are typically the most energy efficient space heaters, consisting of infrared heating elements or quartz tubes heated directly by electrical current. Space heaters with this design are frequently referred to as radiant infrared space heaters. Some are designed with fans, but many are not. A radiant space heater typically radiates heat outward, directly and almost instantly providing warmth to nearby objects positioned in front of it. The heat in non-fan systems rises and creates its own gentle, convective current upward from the elements. In spaces with lower ceilings and smaller air volume, space heaters with a non-fan, radiant heat design provide the benefits of efficiency and quiet operation. On the other hand, the drawbacks of this design are:

• the heat stops almost as soon as the electrical current to the elements stops
• A non-fan radiant-design space heater will not heat large spaces quickly
• mechanisms can wear with use and time, and may eventually need replacing

There is another type of radiant space heater with a slightly different design for effectively heating spaces up to around 150 sq. ft. Similar to a simple radiant design, conductive space heaters directly heat nearby objects positioned in front of them, but do not transfer heat directly to those objects from electrically heated elements. Instead, those elements heat another medium, such as ceramic or a contained liquid (usually a type of oil or water) which, in turn, radiates the heat outward into the surrounding space. The chief benefit of this design is efficiency in power use, as it can actually shut off for a period of time while the conductive medium continues to throw off heat until it cools and needs to be reheated by the elements. This type of design is also offered with and without fans.

Consideration 2: What You Need to Know About Watts, Amps, and Voltage

As you read product descriptions of electric space heaters, you’ll see references to watts, amps, or voltage. The below information provides the basics for good decision making in regard to those aspects of electric power for space heaters.

Watts - Think of a watt as a measure of energy consumption. To heat a room, a space heater typically uses 10 watts of heating power for every square foot of floor area. So a 1,500-watt heater can serve as the primary heat source for an area measuring up to 150 square feet. If it’s used as a supplemental heating source, however, that same heater will be capable of providing added heat to a much larger area.

Amps - This concerns how much electricity a circuit is capable of carrying relative to the demands on it. For example, a bedroom is typically on a 15 Amp circuit breaker. A space heater that operates at 1500 watts maximum, set to its highest setting, will demand, or draw,  12.5 Amps. That leaves only 2.5 Amps on that circuit to power anything else on that circuit (typically, in that room), such as lights, TV’s, phone charging stations, and so on. If there is too much demand, the breaker will trip. When selecting a space heater, whether for a bedroom or a warehouse, be sure you know the Amp capability of the circuit from which the space heater will be drawing power, and then factor that in to your selection criteria.

Voltage - Household power outlets in the U.S. are standard at 120 volts, and accommodate two plugs rated for a total of 15 amps. For these outlets, the standard 120 volt electric space heaters will work well, provided a lot of other electricity is not demanded of the circuit. Larger appliances, including garage and industrial heaters, are powered through 240 volt plugs, and cannot be powered through standard plugs.

Consideration 3: Optional Features for Space Heaters

As you shop for your space heater, you’ll find that a variety of optional features are offered. In advance of your purchase, you should consider which ones will have value to you. Typically, such options include thermostats, programmability, retractable cords, a tip switch, and so on. 

Consideration 4: Safety

Last but certainly not least, safety is a consideration in selecting the right electric space heater for your needs. Here are a few points to consider:

Is the Cord Long Enough? - Space heaters should be plugged directly into a 120 volt wall outlet. Extension cords should never be used with space heaters, because many extension cords are not designed to handle the space heater’s power load requirements, which can lead to cord overheating and a fire hazard. Likewise, power strips should not be used with space heaters.

Does It Shut-Off Automatically? - These features are very important and should be strongly considered. Many models feature a sensor that shuts the heater off if it overheats. Some also have tip switches that turn it off if the heater tips over.

Does It Meet Safety Standards? - Look for a label from a recognized testing laboratory, such as UL (Underwriters Laboratory), or ETL (Intertek), verifying that the heater’s construction and performance meet voluntary U.S. safety standards.

Product Compliance and Suitability

The product statements contained in this guide are intended for general informational purposes only. Such product statements do not constitute a product recommendation or representation as to the appropriateness, accuracy, completeness, correctness or currentness of the information provided. Information provided in this guide does not replace the use by you of any manufacturer instructions, technical product manual, or other professional resource or adviser available to you. Always read, understand and follow all manufacturer instructions.