While all heaters provide warmth to an indoor or outdoor space, they differ in terms of energy efficiency, cost, durability and use. Portable heaters run either on gas or electricity. Of those fueled by gas, natural gas and propane are the two most common fuels used. Kerosene has a few limited applications, but they are minimal compared to the others.

Both gas and electric heaters use a variety of heating methods to distribute heat including using radiant, passive convection and forced air technology that incorporate a ceramic, quartz, halogen or gas element.  Before you use your new heater, make sure to read all the safety warnings.

Heater Types

The many types of space heaters include those meant for the home, workspace and outdoors. Home heaters include fan heaters, wall-mounted heaters, portable and compact heaters, baseboard heaters and radiators.

Portable and compact heaters may be tabletop models, tower heaters or freestanding floor heaters. Workspace heaters are often very similar to home heaters, but they usually have a higher wattage output and may be wall or ceiling mounted.

Outdoor space heaters are most commonly natural gas or propane heaters, but there are outdoor electric heaters as well. They include portable tower patio heaters of varying size and fixed-position radiant heaters. Gas and propane heaters may also be used indoors. Forced air propane heaters provide up to 150,000 BTUs of energy, suitable for spaces as big as 1,200 square feet.

Indoor natural gas heaters are almost always vented and fixed, but unvented gas heaters are also available. The many different types of heaters use a particular heating method to distribute heat throughout a space, whether indoors or out. The methods differ in terms of technology, but some heaters use combination methods.

Heating Methods

The basic way to distinguish between heaters is to ask whether it is a radiant, passive convection or fan-forced heater. Radiant heaters provide direct heat very quickly, heating surfaces and people with either infrared light or an element/reflector combination. Passive convection heaters heat indirectly by warming up the air in a space. They move air over the element, and it rises to fill the room. They take a little longer and are not suitable for outdoor use.

Fan-forced heaters produce convection heat but then use a blower to move it throughout a space in less time than passive convection heaters. All heaters use one of these heating methods, but there is an additional level of categorization necessary to distinguish between all heaters.

The next level of differentiation involves the actual heating element of a space heater, as well as any special feature it uses to move heat. Gas heaters have a fuel source and element that are one in the same. Being combustible, the fuel is the element for gas and propane heaters.

Electric heaters are a bit more varied. Heating elements range from ceramic encased, quartz tubes, metal such as steel or nichrome and halogen lamps. Each of these elements has their own unique qualities. Ceramic is an excellent non-conductor of heat, so it stays cooler than other elements. It also shields the internal element better, producing more energy-efficient heat. Quartz heats up fast for a convection heater and, when used with a fan, spreads heat quickly. Steel and nichrome elements are found in baseboard heaters as well as numerous types of fan heaters and other portable models. Metal elements are also enclosed within wall-mounted electric units. Halogen lamps are used as a radiant heat source and are a part of outdoor electric patio heaters.

In terms of the distribution of heat, an oscillating heater features a motorized fan that moves heat over a wider area. Radiator heaters are another type. Among the most energy efficient, radiators use vertically-situated copper tubes that are filled with diathermic oil and heating elements. The elements warm the permanently-sealed oil which then transfers the heat to the copper tubes. From there, clean heat radiates throughout a room, with no fan required.

Heater Features

The features found on space heaters are provided by the manufacture for both safety and convenience. Look for the UL listing when purchasing a heater of any kind. The mark means the heater meets the industry standards for safe operation. Safety features commonly found on space heaters include tip-over protection to kill the power if the heater falls over, automatic thermal shutoff in case the internal temperature gets too hot and grounded plugs for electric heaters. Direct vent systems are part of certain gas heaters, while unvented gas heaters often feature an oxygen depletion sensor that detects when oxygen gets low in a room. In addition, quality heaters are built from either flame-resistant plastic, heavy-duty enamel or rust-resistant metal.

Convenience features include complete thermostatic control, auto heat and energy-saving settings, digital LCD screens for easy operation and one-touch use. Programmable timers and multiple temperature controls are standard on many space heaters.

Depending on the type and size of space you need to heat, your budget and your preference for a particular fuel source and/or heating method, you literally have thousands of portable and space heaters to choose from. Evaluate your needs first then learn what is available to make the most informed decision.

Heater Brands

There are hundreds of makers of portable heaters. Most of them tend to specialize in one particular area of portable heating such as electric ceramic heaters or forced air propane heaters, although a few manufacturers produce only one type of heater. Popular, well-known heater brands include Delonghi, Honeywell, Holmes, Mr. Heater, Bionaire, Lasko, TPI, Procom, Protemp, Empire, Fire Sense, Coleman, Northern Tool, Crane, Optimus, Qmark and Infratech. That is not a complete list, but it gives you an idea of the number of heater producers out there. The range of heaters these brands produce is enormous, but all of them fall into a distinct category: gas or electric. From there, categorization gets a bit more complex due to the different heating methods used, as well as many heater types.