Portable heater

Hey guys,

I was wondering if any of you can answer my question regarding energy saving. My portable heater has 2 speed (high, low), if I set it at 72 degrees, which will save more energy, high or low? High draws more and get to 72 quicker and also shut off quicker. Low doesn’t draw too much but takes longer to get to 72. Thanks.

I’m in Miami and while it rarely dips below 78* at night, we hit the lower 40s a few weeks back and it was cold for me.

When I replaced my AC air handler 13 years back, the new unit didn’t come with a heating element, as that was evidently an ‘option,’ so off to ChinaMart I went, where I picked up a small electric ‘blow dryer’ and it’s been fine for removing the ‘chill’ a few hours a day.

They are what they are, but maybe get a couple, wear a sweatshirt and some socks and just suck it up?


High vs low is likely how fast the fan spins. The heater will cycle the heating element to get to the temperature you want.

Keep in mind the temperature setting is somewhat fictitious as you are not heating a room, you are heating an open space.

To answer your question, it probably does not make any difference.

I can’t give a definitive answer but i’m of the impression it doesn’t matter, it takes the same heat to raise the room temperature to 72 degrees and the same amount to overcome the thermal losses to keep it there, i don’t see whether putting the heat in quickly or slowly matters too much if both settings are capable of maintaining that temperature.

The only difference i can see is before the room is at temperature where you’d be losing less heat to the outside world with the lower setting as the temperature difference is lower for longer but i don’t think there would be significant difference in the energy usage.

That’s my layman’s guess that assumes an almost 100% transfer of energy to heat in the heater.

I may well have things wrong but my advice to you would be to buy a power meter for the socket that tells you how much energy the heater has used, use the low setting for a suitable period of time (a week?) then the high setting for a suitable time and compare the results. You’ll know for sure then.

here is one of the best videos
i have seen about space heaters….

As the video states, watts is watts.
What I find is that often a lower setting produces a more even temperature range. The heater is not cycling on and off as often,
Thus is more comfortable.

The other key difference is the temperature control.
Seems like all the cheap ones use a bi-metal thermostat. Some have a huge difference temp delta between off and on.
The closer the on-off temps the easier it is to control the room temp.
Also, some run the fan all the time. Others shut the fan off when the heating element is off.

Depending on room conditions, this can make a difference. For example in my office there are 10’ wall to wall floor to ceiling windows.
In the winter the cold air falls down hits the floor and freezes my legs. I have an old milk crate heater that blows air under my desk.
The heater I chose turns off the fan when not heating. This keeps the heater from blowing cold air from around the unit at me.

No really an answer to your question. Just my 2 cents.
All the Best,

i use several of those electric heaters around the house, near the computer, in the bathroom, kitchen, and living room to provide a bit of heat to knock off the chill. The Low setting is around 800 Watts and the High is around 1500 W.

They won’t keep an entire room warm but just the vicinity within about 6ft away from where i am sitting. i run all mine on Low because i have noticed that on some the cord will get warm if it runs on High. The fan only comes On when it is heating.

i set them up in the late fall and put them away in the spring. My thermometer indicates it is 65 right now but i feel fine since i bundle up with layers of wool as needed, and i prefer a cooler temperature for sleeping like on a 3-dog night.

Use whichever setting keeps you more comfortable; the difference in energy usage, if any, should be negligible.

Generally it shouldn’t make much difference.

Low speed means it doesn’t push the air around all that much, so if the heater’s close to you, you have a better chance of just heating up the necessary pocket of air where you’re sitting. If you want to heat the whole room, you’d want the high setting, and/or have a separate fan mix the air around.

On the yootoob, the Eddie Munster guy, “Technology Connections”?, had a coupla videos about heaters and “room size” when they’re all the same wattage.

Ah, and there’s Eddie!

He funny.

If its a plug in space heater then both are identical, 100% efficient.

Really the only answer this is to measure the current draw from the unit. A clamp meter and a line splitter….the cheapies like the Uni-T models are fine, or borrow one if buying a clamp meter will eliminate any savings from running one setting or the other. It’s surprising to see what is actually being pulled from the line vs. what’s stated on labels (hint: many labels are comically inaccurate - high or low, both ways - and “comically” can also mean fire hazard if you have one of the gems that says 1200w on the label but actually pulls 16.2 amps from the wall….or especially when they do not have failsafes in place to shut the element off if the fan happens to fail…meltdown city).

Assuming the area has reasonably still air and typical insulation (i.e. not a drafty metal building), and assuming it isn’t bigger than what the unit says it’s made to heat comfortably (typically 10x10 with residential ceiling height)……then it shouldn’t matter much unless you discover that high is 12 amps and low is 8 amps and the heat output on low is noticeably less. In a larger room then I’d say pump it out on high until things stabilize and the walls and furnishings absorb some of that heat to where the heater will start to work less unless there’s a lot of air movement, then you can leave it there or put it on low. But really, current draw tells you the most. One question I just gave myself and don’t know the answer to is whether efficiency for typical element types is the same at varying currents…I would assume it is with nichrome wire and such, but I don’t know.

Infrared heaters are where it’s at, if it’s just for human skin comfort, but they have a limited range.

Yeah, I was gonna mention that.

Without exception, Every Single Heater that I ever got which had a fan, has had the fan crap out after a while. Induction motors, always one winding or another would pop, or at least just lose contact, so it’d be running on fewer windings. So what was high is now medium, and what was medium is now low. Or if just high/low, it’s now low/nothing.

Last heater that I had at work did that. Keep it on high-heat for too long, and the thermal breaker would pop. Not enough air being pushed through the elements, that hot air would bottle up inside the enclosure where the breaker was, and pop.

And it was and still is a beautiful looking motor, shiny mirror-finish metal, etc., not the usual Chinese Mystery Metal stamped into laminations. Damn.

Anyhoo, got one of those 2-“bar” quartz heaters that worked nice. Could toast English muffins at work if I wanted to, by just dangling ’em in front of the thing.

Conservation of energy says those electromotive watts turn into a combination of light watts and heat watts. It’s why most electric heaters are considered 100% efficient.

Inefficiency of electric heaters comes in the form of electric generation / infrastructure and pricing. Gas costs less per heat watt delivered to your house for any fully functional gas heater.

It depends on how well the space being heated is insulated and how much heat is being generated compared to the size of the heated space.
Start on high and when the temp desired is 10 degrees below what is set, turn to low.
There are a lot more variables but this may help.

It seems like your fan speed is also affecting how many plates are powered and make heat, i have a heater like tat too, there are 2 ceramic heating elements, i can turn on 1 or 2.
So in that case, you can find out your answer relatively easy, in most cases those 2 half are the same, so the draw is double when 2 are powered, just time how long it takes to got to 72 and shut off, if it takes less than half the time on high , vs low, then you are burning less kw on high, to get to the same temp. if on low it takes less then double time than the heater is more efficient in low mode, of course the fan also draw more on higher rpms, but the difference is not nearly as big as with heaters. might as well ignore it. or you can simply throw a ammeter clamp and see real time consumption

I would suggest buying a kill-a-watt (or generic plug-in ammeter / wattmeter), they are under $20. It will tell you exactly how much power you’re using. Most of them even have cumulative watt hours as well, so you can run it over a 24-hour period. I got one and ended up plugging it in to all my appliances, it’s a very informative tool, that I believe everybody should have.

As far as what would be more efficient for heating, low or high, I don’t think it matters much. Let’s say your room takes 10,000 watts to heat up (I’m using easy rounded numbers here for math). Your heater could either put out 1,000 watts for 10 hours, or 500 watts for 20, except for a very minor difference in the fan speed, it should use pretty much the same amount of power.

My little portable heater is LOW = 750 Watts & HIGH = 1500 Watts.
Fan speed is same for either.
As far as energy saving between the two settings, I have no idea. That said, I run mine on LOW.

This kind heats better than the rest.

Because not only does it produce the usual amount of actual heat, but the fake flames warm you psychologically! :smiley: (Warmth as an emotional state)