Projects & Improvements

Here’s What to Know About the Differences Between Convection and Radiant Space Heaters

updated Dec 23, 2020
We independently select these products—if you buy from one of our links, we may earn a commission. All prices were accurate at the time of publishing.
Post Image

When you’re sitting at home, wrapped under 40 blankets in efforts to keep the electric bill down, knowing the difference between types of heaters is probably the least of your concerns. But rather than resorting to wearing your puffer coat indoors, understanding what space heater is best will allow you to pick the best one for your situation and may even cut back on your monthly expenses.

Chuck Schwartz, the HVAC Director of Training and Technical Support at Ferguson and Randy Light, the Senior Merchant of Portable Heating at The Home Depot, both gave us the rundown on convection and radiant space heaters so you don’t feel like it’s a shot in the dark the next time you’re shopping for one.

But before the differences get addressed, there are a few general rules of thumb to keep in mind when you have a space heater—no matter the type. Light says, “Space heaters should be maintained and used according to the manufacturer’s directions, in order to avoid the risk of fires,” continuing that most models these days have some kind of safety tech to lower the hazard, including adjustable thermostats, automatic overheat protection, tip-over protection, and cool-to-the touch features. 

He also suggests keeping heaters away from flammable objects and water, allowing plenty of space for ventilation, avoiding using them with an extension cord, and unplugging them once you leave the room. Following these guidelines will ensure you’re being as safe as possible while you’re cozying up your room. All prepped? Here’s what to know about convection and radiant heaters.

How does a convection heater heat a room?

A lot of science goes behind what many would consider a basic heater. “To understand convection heat, you need to know that there are three basic types of heat transfer: conduction, radiation, and convection,” says Chuck Schwartz, the HVAC Director of Training and Technical Support at Ferguson. “Conduction is when one object touches another. Most everyone has experienced conduction when they grabbed the hot handle of a pot.” He explains this is opposed to radiation, which “travels via waves without any medium such as the pot handle.”

So how does this reaction work when it comes to warming up your space? “First, it heats an element component inside the unit with electricity, then transfers the heat into the air using a fan or natural rising warm air, making sure the heated air is distributed evenly throughout the room,” explains Light.

Credit: Erin Derby

Are convection heaters expensive to run?

While there is a lot of annoyance that comes with the cost of heating your apartment or home in the winter, convection heaters are quite cost efficient and may help you lower that heating bill. “Your average convection heater uses 1500 watts of electricity per hour. The actual cost to use the heater is based on local electrical rates. Based on national averages, it may cost around $0.20 per hour to use a convection heater,” says Light. He also mentions that this can save a lot of money in comparison to other heaters, since you’ll be heating one room rather than the entirety of your home. 

Convection vs Radiant Heaters: How Are They Different?

“The difference between the two types of heaters is based on the heat transfer—one needs a medium for the heat to travel and the other does not,” says Schwartz. “A convection heater works by allowing air to pass across the heater. As it warms, it will rise and travel on molecules of air or water from hot to cold. The air across a convection heater can be natural or forced with a fan. Typically, calling something a convection heater suggests the natural convection of air moving without a fan.”

As for a radiant heater, Schwartz says it doesn’t need air to pass across the surface; rather, it passes through radiant heat waves until something (like you) absorbs that heat. But of course, there are more to heaters just than that, and there are different types of subcategories under radiant and convection heaters. Light broke down these differences, too. 

“Ceramic space heaters are a type of convection heater that warms the air over hot ceramic plates using a fan. The body of the heater stays cool to the touch and the heating element lasts for many years,” says Light, adding that this is often a great choice for homes with kids and pets. There are also forced air heaters (aka fan-forced heaters) which warm and move air through the use of fans. He says these are popular among offices and small work spaces.

You also might be familiar with oil-filled heaters, which Light says are both convection and radiant, because they heat the air and give off a radiant heat when you’re nearby. “These are ideal for a living room, bedroom, or den and tend to retain heater for longer periods of time, even when the power is turned off. This helps maintain an even temperature in the room. Lastly, Light points to infrared heaters, which are especially useful for small spaces, like under your desk or in a bedroom. 

Now that you’re equipped with the right knowledge, shop the following three heaters to help you stay warm and toasty.