Great space heaters for your buck

Warm up this winter with Delonghi's $80 TRH0715T Safeheat 1500W portable oil-filled

Published November 18, 2012 5:00PM (EST)

This article originally appeared on The Wirecutter.

The Wirecutter Maybe your home's heating system just isn’t cutting it, and wearing your coat indoors for the next six months is just stupid. If you rent your home, or can’t afford to install new insulation or upgrade your central heating system, then the best way to stay warm short of piling on extra layers of clothing is to buy a space heater.

If you're looking for an inexpensive portable heater to help keep your home warm this winter, Delonghi's $80 TRH0715T Safeheat 1500W portable oil-filled radiator is the way to go. After 20 hours of research and hands-on testing of 11 different space heaters, it was the offered the best combination of price, energy efficiency and features that I could find. But, if you've got money to burn, Dyson's $400 AM04 Hot fan-forced ceramic heater is a great option too. It's packed with features, safer than anything else I tested and  heated up my test space so much faster than everything else I pitted against it. But before we talk about what you should buy, there's a few other things we need to talk about.

Safety First

A space heater can turn your quality of life up to eleven, but if misused or neglected it also has the potential to really mess up your place. In a 2011 report, the National Fire Protection Association stated that “space heating poses a much higher risk of fire, death, injury, and loss per million users than central heating." In the same report, the NFPA estimated that between 2005 and 2009, 20,580 fires were started by space heaters. To learn about the best way to safely use a space heater, I spoke with Gary McCall. He's the Fire Advisor to the Office of The Fire Commissionerfor British Columbia's Vancouver Island Region. After 30 years as a firefighter and fire chief, he knows about stuff that burns other stuff.

Make sure that the portable heater you buy is approved by Underwriters Laboratories or if you live North of the Wall, the Canadian Standards Association.

“The first thing people need to understand is that space heaters really aren’t intended to be a primary heating source,” explains McCall. “They’re a supplementary heating source only, and my guess is that if they’re being used as a primary heating source, people will move as close to them as possible to get the maximum heat, and that’s where the danger comes in.” McCall told me that the first, perhaps most important step in staying safe while using any portable heater is to ensure that the one you wind up buying is certified by either the CSA or the ULC (or just plain old UL in the United States). The second thing to remember? Read the heater’s manual. “They all come with manufacturer’s instructions on how to use them and how to place them,” says McCall.  “A general rule of thumb would be no combustibles within three feet of the heater, but it’s also really crucial to look at the manufacturer’s instructions.”

No Extension Cords

McCall also mentioned that when it comes to space heaters, extension cords are generally the enemy. “You’ve got to be very careful with that,” says McCall. “A lot of manufacturers will tell you flat out that you shouldn’t be using the heater with an extension cord. If they’re OK to use with an extension cord, you’ve got to be sure that the cords are rated for the power that the heater’s going to use. If the cord becomes a trip hazard, people tend to maybe put them under a carpet or something like that. That can bring its own risks. There, you have a situation where the cord isn’t designed to be used in that manner.”

Most portable heater manufacturers recommend against using their products with an extension cord. You'll likely want to take their advice on the subject.

So that’s safety in a nutshell. Let’s talk about the hardware. Space heaters can be slotted into two basic categories: radiant heaters and convection heaters.

Radiant/Infared Heaters

The most basic explanation I can give you of radiant heaters is that they use infrared radiation to keep you warm.  Electricity is sent into a heating element, which produces a wavelength of infrared radiation that feels warm to us. This radiant heat is typically focused against a reflective surface and bounced out into the surrounding area, warming up a small chunk of space around the heater.  Radiant heaters are great for rapidly raising and maintaining the temperature of a small area. Unfortunately they take forever to warm up a larger area. To speed things up, most radiant heaters come equipped with fans that push the heater’s warmth out to the rest of the space it’s in at a better clip, but, having grown up with these things, I can tell you that while the fan gets the job done eventually, you end up with spotty inconsistent heat when you use a radiant heater in a large room. There’s two major technologies employed in radiant-style heaters: wire element and quartz.

Wire element heaters produce a large amount of heat, but also have a dangerously high operating temperature.

Wire element heaters are what most people think of when someone says ‘space heater’. They operate the same way that household toasters do: You plug the heater into the wall, turn it on and just a little too much electricity is sent coursing through a array of high-resistance wires. These wires almost instantly start to glow red-hot and heat up to temperatures as high as 1000 degrees Fahrenheit. The heat is directed outwards from the wires with the help of that reflective backing and fan we were talking about. Like all radiant heaters,  they’re great for rapidly heating up small to mid-sized areas in a short amount of time. But when the power is cut to a wire element heater, the heat dissipates almost immediately. These things are infamous for being Hell-powered death machines that will burn down your house if you so much look at them sideways. I had one in my bedroom when I was a kid, and can’t count the number of times I burned myself on the thing over the course of a winter. Also, in the mid-nineties, a good friend of mine lost his fiancee to one. She fell asleep, left the heater running and it proceeded to burn her home to the ground. That said, they’ve become significantly safer to operate over the past decade, thanks to the inclusion of new features like overheat shut-down controls and tip-over switches that shut the heater down if it, you know, tips over.

Quartz element heaters are a little safer than wire element heaters, but I wouldn't turn my back on one.

Quartz element heaters work in much the same way as wire element heaters do, but they’re a little bit safer to turn your back on. This is due to the fact that they sheath the heater’s wire element inside of a quartz tube. This quartz sheath also makes them more efficient, as the sheath insulates the elemental wire, allowing it to heat up faster without using as much electricity as an unsheathed wire element does. As with wire element heaters, you get a boatload of radiant heat that can be pushed around the room by a fan. They heat up fast, but their heat dissipates quickly after they’ve been shut off.

Convection Heaters

Convection-style heaters are designed to pull cold, room temperature air over a heating element, and in doing so, warm it up. Typically, they take longer to heat up an area than a radiant heater might, but the heat they generate is more even, meaning less cold spots for you to put up with. Here’s the dumbed version of how they work: Just like an element in an electric oven, convection heaters start to warm up when electricity is channelled into a resistor, which in turn changes the energy into heat. This heat is then spread through a conductive mass such as a tank full of oil or ceramic plates, which in turn heat up. The air around the conductive mass is then heated. The hot air rises and is replaced by cold air. Wash, rinse, repeat until the whole room is filled by warm air. The two major flavors of radiant heaters are oil-filled radiators and ceramic heaters.

An oil-filled radiator's size and efficiency make it a great choice for warming up a larger space.

Oil-filled radiators employ a sealed tank full of oil in order to produce heat. The oil is heated electrically, which in turn heats the walls of the tank. This heats the air around the heat around the tank which then radiates outwards, drawing cold air in towards the radiator to heat it up and send it back—you get the idea. This round about way of pushing heat out into the room is called convection heating. Oil-filled radiators hold their heat long after the electricity to them has been cut. Their efficiency and the crazy amount of heat they can generate make oil-filled heaters are a great choice for use in a larger area, like a living room.

Ceramic heaters heat up quickly, and hold on to their warmth for a long time after being turned off.

The other option for portable, radiant warmth is ceramic heaters: the wire element heater’s sane, younger brother. Ceramic heaters function in much the same way as wire element heaters do, with one exception: The wire elements used are encased in–you guessed it–ceramic plates. These plates heat a series of metal (usually aluminum) baffles. The heat collected in the baffles is then circulated throughout the heater’s immediate area with a fan. Ceramic space heaters cost roughly the same as wire element space heaters and can introduce the same amount of warmth into a given space, but are considered to be a whole lot safer. Why? Well for starters, the heated ceramic plates in one typically reach a maximum surface temperature of 460 Fahrenheit—that’s under half of the maximum temperature of a wire element heater. So a ceramic heater will be less likely to ignite any flammable materials in its immediate area—a bonus if you plan on using it in a small space, like under your desk, for example. Ceramic heaters are more efficient than their wire element counterparts too: where wire element heaters rapidly cool off as soon as soon as you cut the power to them, a ceramic heater’s plates will radiate residual heat for some time after the heater’s been turned off.

So That’s What We’re Dealing With  

I’m sorry, but screw wire element heaters and their quartz-peddling buddies too. If you want to use one in your workshop or garage, ok. But do you really want to screw with what basically amounts to a bunch well-organized exposed wires in your home?  The answer is no, you don’t. Even with safety features like tip-over sensors and high temperature switches, they get too damn hot and are just too damn dangerous.  This, along with the fact that the heat they generate dissipates so quickly makes them, in my opinion a poor choice for anyone that wants to stay warm without having to keep their space heater running constantly. The same goes for kerosene and other combustion-based portable heating systems. I've used one in the past on winter camping trips to Cape Breton Island, but given the amount of ventilation required to use them safely it's not a piece of kit I'd want in my home. That means that convection heaters are the only horse left in this race. So let’s talk about how to pick one.

What to Look For

Depending on how well the room you want to heat is insulated and whether or not there’s windows or doors leading outside built into the walls of the room, You’ll need between 10 and 15 watts of power per square foot. So, a 100 square foot bedroom, for example, requires at least a 1000 watt heater to keep things toasty. Unfortunately, the most powerful heater you can plug into a wall maxes out at 1500 watts–which makes it suitable for heating a meager 150 square feet. Again, about the size of a large room. As McCall mentioned earlier, these things are designed to provide supplemental heat. That said, if your the area you want to place a portable heater in is reasonably insulated, given time, it will heat the room up, even without any other heat source to help it along. But again, these things are for spot heating rooms when you don't want to heat your whole house and you just need to up a single room a few degrees. So, let's focus on picking up something that's reasonably priced, powerful, packed full of features and above all else, safe.. What features should you look for? Well, If it were me, I'd want the following:

  • Multiple heat settings: While wattage dictates the amount of heat a portable heater us capable of producing, most offer multiple heat settings that either controls the amount of heat being produced, or in the face of fan-forced heater, slows down the heater's fan so and in turn, the amount of heat being pumped out into the room.
  • You’ll want it to have a tip-over switch, and a heat sensor that shuts the heater down should it become dangerously hot.
  • Oscillation: If you decide to buy a fan-forced ceramic heater, having the option to oscillate the device from side to side allows the heater spread its heat to a larger area than a stationary fan can manage.
  • Cord management: space heaters should be easy to store when they're not needed. Most have built-in cord management systems.

Testing

Here's the thing: no one really tests space heaters extensively. There's a lot of reviews of individual heaters, but nothing that really allows you to figure out which one is best. The closest I was able to come to anything that resembled a portable heater roundup was from Consumer Reports. They looked at 20 different portable heaters, and gave each one a rating out of 100. Unfortunately, CS shared virtually no data on how they arrived at their decisions of how to rate the heater, so I had to come up with my own test criteria. Over the course of close to 20 hours of research, I found that the most common wattage for space heaters is 1200 and 1500 watts. Many of these will operate at lower wattages as well, but as even the most powerful space heater in the world isn't capable of efficiently heating a 225 square foot bedroom, I think that maximum wattage is more important than minimum wattage. With this in mind, I focused on finding the best ceramic heaters and oil-filled radiators I could in a 1200 to 1500 watt range. I started off by looking at 32 different heaters, produced by  Honeywell, Optimus, Sunbeam, Dyson, Delonghi, Crane, Holmes, Lasko, Impress, Vornado, Bionaire and Sumpenton. Thinning the herd was easy: anything that didn't offer basic safety features like a tip-over switch, or the ability to shut down to prevent overheating was nixed. Anything Without CLA or ULC certification? Gone. Any hardware that had a poor user reviews, was available online or in store, but wasn't listed on the manufacturer's website was disqualified too. In the end, I wound up with six fan-forced ceramic plate heaters in a 1200 or 1500 watt capacity (although a number of them also had the option to step down to lower wattages as well,) and four different 1500 watt oil-filled radiators. I chose to use my 160 square foot bathroom, which has an exterior window and one door that opens into my home's interior, as my test space. As portable heaters are designed to provide supplemental heat, I opted to test how long each device, cranked up to its maximum setting, would take to warm the bathroom's base temperature of 64.4 degrees Fahrenheit to 69.8 Fahrenheit with the window and door closed. I placed each heater at one end of the room underneath the bathroom window, and a digital thermometer at the other end of the room, turned them both on and waited for the magic to happen. Along with heating time, I also tested the true wattage being drawn by the heater while in it was in operation, the amount of money it'd cost to operate each unit for a month and how much it'd cost to run each heater for a year.

The Best Portable Heater

The $60 Delonghi TRD0715 Radiator was the most efficient portable heater of those I tested.

All things considered, the $80 Delonghi TRD0715T Oil filled Radiator is the best portable heater of the ten that I tested, and it'll make most people happy. The TRD0715T managed to raise the temperature of my bathroom to 69.8 degrees Fahrenheit in 27 minutes and 13 seconds. This was the shortest amount of time of any of the fan-forced ceramic heaters or oil-filled radiators I tested, with the exception of Dyson's AM04 Hot (which we'll get to in a minute.) The  TRD0715T features three different power settings–700, 800 and 1500 watts–and a basic thermostat, which are controlled by an analog knob and slider respectively. Do these allow for the precise temperature control that a digital system might? No, but you're not going to bake a cake with this thing, you're trying to take the chill out of the air in your bedroom, or maybe keep the frost out of your pipes in the basement, so it's not a big deal. It also has a 96-setting timer built into it, making it easy to set the radiator up to turn off when it best suits you.  While the TRD0715T is a 1500 watt device, my testing showed that while running full bore, it peaked at 1272 watts of use. When used for supplemental heating, it'll cost you about $40 a month to run. That's the cheapest monthly operating cost of any of the 1200 or 1500 watt heaters I tested. If you needed to heat a modestly insulated room with it, you totally could. After turning off the heat in the bathroom and leaving the TRD0715T to do its thing for an hour, it managed to warm the room up from 53 degrees to a balmy 70 degrees. It's also worth mentioning that aside from the occasional ping of expanding metal, this thing is whisper quiet, making it a great heater to use in a bedroom at night. I'd like to be able to share some positive editorial reviews on this thing, but I couldn't find any. But there weren't any bad ones either, so we're cool. That said, the reviews for the TRD0715T were overwhelmingly positive on Amazon. Also, after submitting my results to him, Brian Lam told me that he owns  a TRD0715T, and didn't have any complaints about it to share. He's smart and picky, so I'd call that a good sign that you'll like it too. However, as cheap and efficient as this thing is, there were a few things I didn't like about it, starting with the fact that, it's kind of a fatty. As it weighs 24 pounds and takes up 9.1” x 13.8” x 25.2” worth of space, calling the TRD0715T a portable heater is hard to do with a straight face, but as it can be rolled around on caster wheels, its heft shouldn't be an issue so long as you don't need to haul it up or down a flight of stairs on a regular basis. There's also the fact that the radiator's surface temperature reached a high of 174 degrees Fahrenheit. That's hot enough to be painful, or with extended exposure burn someone, so given its large surface area and the fact that it sits in the floor, anyone with small children toddling around might want to think twice before buying one. That said, most of the heaters I tested had far higher surface temperatures. The worst offender for this was the Sunpentown SH-1507 Mini Tower Heater's heating element temperature peaked at 244 degrees Fahrenheit. It's also worth mentioning that the Delonghi TRD0715T is that some owners of the radiator complained on Amazon that it emits a foul odor when operating, but I didn't detect anything, even after leaving it running for several hours in my garage to be sure. Neither did Brian. But the TRD0715T might not be for everyone. If you want to have a little more control over your heater's temperature,and time than the Delonghi radiator affords, you might opt for Honeywell's HZ-709 7 Fin Oil Filled Radiator Heater with Digital Controls. It costs the just about the same as the TRD0715T, and as its name suggests, offers a digital thermostat, and a 1-12 hour timer. But it's not nearly as energy efficient. The HZ-7097 cost $63 a month to operate. The same can be said for the $100 Bionaire Digital Oil-filled Radiating Heater. My testing showed that it cost an additional $19 a month to run. Or maybe an oil-filled radiator's just too damn big for the space you want to warm up. The convenience of not freezing your ass off gets old in the face of tripping over a heater every time you walk in a room pretty quickly. In that case, you might want to look at a fan-forced ceramic heater like the 600/1200 watt Crane EE-6353 600/1200 watt ceramic heater. It costs $55, is only 20" tall, comes with a remote control oscillates and has a built-in shutdown timer. That said, it's more expensive to operate than the more power 1500 watt TRD0715T, and I found it to be kind of top heavy, making it easy to knock over. Even with a tip-over switch, that's a deal breaker for me. I found the 1500 watt DeLonghi DCH1030 Safeheat to be a lot more stable, and selling for $25, it's also one of the cheapest heaters I tested. But unlike the Crane, the Safeheat DCH1030 doesn't oscillate, plus it costs $81 per month and $967 a year to operate–$72 and $478 a year more respectively than you'll have to pay to use the TRD0715T. I also tested  the Sunpentown SH-1507 Mini Tower Heater, a Holmes HFHVP3, and a Crane's EE-6490 Space Heater. They all had hotter surface temperatures, took longer to heat the room and were all less energy efficient than the TRD0715T was. Aside from the Dyson Hot, which we'll get to in a minute, Optimus' $45 Electric Portable Oil-Filled Convection Radiator Heater's was the only heater I tested that had a cooler surface temperature than the  TRD0715T's. It weighed four pounds less too. Unfortunately, despite being $35 dollars cheaper to buy initially, the Optimus took 35 minutes and 42 seconds to heat the test area, and at $52 a month and $627 a year to operate it's not as good a deal as the Delonghi radiator in the long run. One of the interesting things I discovered while testing all of these heaters was that the difference in performance offered by a 1200 watt and a 1500 watt heater is minimal, with neither wattage offering any real gain or reduction in heating efficiency. Honestly, it's all over the board, and that 1200 and 1500 watt hardware is priced similarly further complicates things. So if I were shopping for one, I'd completely ignore the wattage and base the decision of which one to buy on price, safety features and energy efficiency. If Money's No Object

Dyson's Am04 Hot: Wicked fast. Wicked expensive.

You'll want to buy a Dyson AM04 Hot. Priced at $400, it's the most expensive piece of hardware I tested by hundreds of dollars, but it was also the best looking, most functional and fastest heater I was able to get my hands on. The Dyson Hot is a 1500 watt fan-forced ceramic heater that, thanks to Dyson's proprietary Air Multiplier technology, was able to bring the bathroom up to 21 degrees Celsius in just 16 minutes and 44 seconds. That's close to 12 minutes faster than the TRD0715T could manage. When I put it in a room that started off at 53 degrees up to 77 degrees in 60 minutes, making it faster than the Delonghi TRD0715T once again. More than this, the AM04 Hot's surface temperature never got above 84 degrees Fahrenheit. If this were the middle ages, people would try to burn this thing for being a witch. In addition to it's high-speed heating abilities, the AM04 Hot is compact, comes with a remote control, can both oscillate and tilt, has and 10 fan speeds and 99 heating levels. As if this wasn't already enough, when the warm weather comes, you can turn the thing's heating element off and use it as a fan (yes, most fan-forced heaters can do the same trick, but the Dyson's actually goodat it.) It's crazy! Or maybe just crazy expensive. In addition to being the most expensive piece of gear I tested for this roundup, the AM04 Hot was also the most expensive to operate: $112 for a month, which over the three months of cold weather most of us in North America experience adds up to $336. But if you have $400 to blow on a portable heater, I think you can likely afford it. Now let's say you can afford it: do you want to spend $400 on a heater? Probably not. For $320 less you could buy a TRD0715T, and enjoy a per month operating cost that's $72 lower. That adds up to $200 less for the winter. So, in your first season of ownership, buying the Delonghi radiator instead of the Dyson Hot will save you almost $720. When you think of all the things you could do with that money, it's hard to justify the Dyson Hot's price.Popular Science and Wired.com agreed with me on this one: as cool as it is, it's just too frigging expensive for what it does.

If You're Colder than Everyone Else in the Room

Lasko's My Heat Personal Ceramic Heater's small size comes at a steep price in comparison to other more powerful heaters.

Let's say you don't want to heat a large area. Maybe you just want to stay warm while your stuck at your desk at work. In that case, you might want to consider picking up Lasko's My Heat Personal Ceramic Heater for $18. At 3.8" x 4.3" x 6.1", it's small enough to set on top of or under a desk without getting in the way, and as it only cranks out 200 watts of heating power, it's strong enough to keep you warm without roasting your co-workers at the same time. It has an almost laughable $9 per month and $104 per year operating cost for those keeping score. But it has a number of issues stacked against it. For starters, while the My Heat Personal Ceramic Heater offers a cool touch housing and an overheat sensor, it only has one heat setting and lacks a tip over switch, which as you could be using this thing in close proximity to your body, I think I'd kind of want. It's also worth mentioning as you'd only be using this thing to keep yourself warm, the money you'd pour into its monthly operating cost might be better spent on a sweater, which would give you a bit of added warmth no matter where you go. There's also the fact that given the fact that $18 is a little steep for a 200 watt heater. For $2 more, you could also pick up a two-pack of Holmes' 1200 watt HFHVP3 heaters from Amazon. The HFHVP3's monthly and annual usage costs are significantly higher than the My Heat Personal's are, but then it does crank out 1000 more watts than the Lasko can. Then again, it's usage costs are significantly higher than those of a 200 watt heater: $61 per month and $736 per year. Whatever you end up buying, use it safely.


By Seamus Bellamy

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