# Does a heater using candles and flower pots really work? **URL:** \ **Category:** Factual Questions\ **Created:** [February 1, 2014, 10:11am UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271 "2014-02-01T10:11:20Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Musicat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/musicat/32/20189_2.png) [@Musicat](https://boards.straightdope.com/u/Musicat)\ **Post date:** [February 1, 2014, 4:37pm UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/21 "2014-02-01T16:37:53Z")
> [@Musicat](#): > > I think their goal is just to fool the unwary and get video hits; they certainly don’t benefit monetarily. > [@Musicat](#): > > There certainly is a benefit from getting video hits. Youtube pays uploaders by the hit if this feature is enabled. Just to clarify my seemingly contradictory statements…if the YouTube video isn’t promoting a product he sells, the poster isn’t making any money from product sales. However, the poster may be making money through YouTube from the hits, or getting extra YouTube privileges from the quantity of hits. > [@pulykamell](#): > > I don’t know if I saw the fake 9V one or not (it sounds vaguely familiar–but you can fit AAAAs in a radio that takes AAAs with a little finagling), but I do remember [this fake 6v hack](http://s166.photobucket.com/albums/u90/snopesbinary/Humor/?action=view¤t=batteryhack.mp4) video from a few years ago. That may be the one I was thinking about. I got a few facts wrong, but remembered the concept. ---
**Author:** ![johnpost](https://avatars.discourse-cdn.com/v4/letter/j/f17d59/32.png) [@johnpost](https://boards.straightdope.com/u/johnpost)\ **Post date:** [February 1, 2014, 4:44pm UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/22 "2014-02-01T16:44:23Z")
there is a huge risk of fire. people leaving just a few decorative candles burning unattended set their houses on fire. you also need to provide oxygen for the candles to burn and a method to safely remove the carbon monoxide from the living environment. people believe this because people are stupid. living in our current reality is expensive and unpleasant, people want easy answers to life. people winter camp with little to no heat. insulate yourself (put on long underwear, sweatshirt and sweatpants, warm hat, fingerless gloves) and you can be at 50F. ---
**Author:** ![aruvqan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aruvqan/32/2891_2.png) [@aruvqan](https://boards.straightdope.com/u/aruvqan)\ **Post date:** [February 1, 2014, 5:01pm UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/23 "2014-02-01T17:01:40Z")
I will say that we managed to heat our bathroom with one based on one of the reasonably large jar candles [22 oz] from Yankee Candle that someone gave us for Christmas. Using the 3 graduated size pots, 2 saucers and a scrap metal tripod thingy to hold the clay pots over the lower saucer and candle. Our barn bathroom is 6’x12’x7’ceilings [I think that is how tall the room is.] We did have to cover the window to reduce radiation of the heat to the outside and damp any possible draft from around the window and keep the door shut to hold the heat in. I would say that it maintained a reasonably comfortable 50F when the temp outside was at 0F. Someone sent me a link to a lifehack on making one and we wanted to see if they were any good. I wouldn’t try heating any more than a bathroom and a small bedroom [might take 2 for the bedroom] but if you are trying to both light your bedroom and keep warm, bundling up in bed with one on each bedstand to generate a few degrees of heat and some light is plausable. I was considering posting to the mythbusters site for them to do the math for the rest of us math ignorant types. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [February 1, 2014, 7:15pm UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/24 "2014-02-01T19:15:11Z")
> [@Musicat](#): > > And some 9v batts have flat, stacked cells. I haven’t seen the video I was thinking about recently, but there was one that purported to have usable (AAAA is not very usable) AA or AAAs – I forget which. It showed an experimenter opening up a 9 v batt and putting the smaller ones in a radio. Easy to do in edit. Besides, I doubt if you’d save much money even if you could find AAs inside, and that was the gist of the video. It was designed to get eyeballs, not spread truth. Ah, if they were claiming there are AAs inside, that certainly would be a fake (although I’ve also seen videos that show you how to use an AAA or AAA in place of an AA by padding one end with a wad of foil). ---
**Author:** ![Sigene](https://avatars.discourse-cdn.com/v4/letter/s/df788c/32.png) [@Sigene](https://boards.straightdope.com/u/Sigene)\ **Post date:** [February 1, 2014, 8:34pm UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/25 "2014-02-01T20:34:00Z")
I apologize for not reading all of the responses to this thread, so may have missed something. I saw some of these video a few weeks ago and made one last week with two flower pots and tea candles. I sealed the hole in the internal pot, and loosely covered the hole in the external pot to maintain the heat in the pot better. Yes the external pot get surprisingly warm, and the internal pot gets downright hot. To the point I can’t touch it. Does it warm a room noticeably? I didn’t think it did much to warm my 20 by 15ft room, but I also had the door open and my wife (who is more suggestible) thought it did. My official answer…I don’t know, though it would definitely depend on the size of the room and if I had the door shut. Would it work better than 4 candles just lit in a room? Not sure…it seems the heat given off is the same regardless if it was captured in the pots or not. It does seem that the heat doesn’t go directly up to the top of the room so may be a bit more advanteageous to be ‘captured’ in the pots and radiated out. I think it would definitely warm a small room or keep my feet warm under my desk…if you want to risk the potential fire hazard. Candles are cheap, but I don’t think full time heat from a set of these pots would be cheaper in the long run. Am I glad I did it and would I do it again and use it? Yes, most definitely. It’s entertaining, I get to experiment and Learn something. And it does seem to get hot enough to actually provide some heat. ---
**Author:** ![Charlie\_Wayne](https://avatars.discourse-cdn.com/v4/letter/c/4bbf92/32.png) [@Charlie\_Wayne](https://boards.straightdope.com/u/Charlie_Wayne)\ **Post date:** [February 2, 2014, 3:18am UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/26 "2014-02-02T03:18:22Z")
For all of you who claimed these things are fire traps: Yes. There is no doubt that anything that has an open flame could start a fire if the flame comes into contact with something that will burn. But if you construct these things carefully, so that the candles are in a metal tray or similar container and the tray is placed on top of a surface that will not burn and away from any other materials that can catch fire, you can be almost certain they will be safe. The biggest danger of starting a fire is if you have pets or small children and you cannot keep them away from these “heaters”. But if you are very careful and you find a way to prevent children and pets from knocking them over, you can probably lower the danger of starting a fire to the point where you feel safe … at least “safe enough”. However, I would never use one of these without having a working smoke detector and fire alarm. ---
**Author:** ![Musicat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/musicat/32/20189_2.png) [@Musicat](https://boards.straightdope.com/u/Musicat)\ **Post date:** [February 2, 2014, 3:37am UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/27 "2014-02-02T03:37:26Z")
> [@Mangetout](#): > > Ah, if they were claiming there are AAs inside, that certainly would be a fake (although I’ve also seen videos that show you how to use an AAA or AAA in place of an AA by padding one end with a wad of foil). I think **Pulykamell’s** link in post #20 is probably what I was thinking of. Equally fake. ---
**Author:** ![Kevbo](https://avatars.discourse-cdn.com/v4/letter/k/e47774/32.png) [@Kevbo](https://boards.straightdope.com/u/Kevbo)\ **Post date:** [February 2, 2014, 3:53am UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/28 "2014-02-02T03:53:27Z")
With an open candle, the flame heats a fairly small flow of air to pretty high temperature. This air then convects up to the ceiling, where it is appreciated by the odd spider. By using this hot air to heat the pots, you have a bit of surface area radiating near where the people hang out. In addition you heat a larger flow of air (to a lower temp, of course) which won’t move to the ceiling as fast. Like the various flavors of electric heaters, you don’t get any more actual heat, but there are ways to better or worse use what you do get to keep people warm. But trying to heat burning wax with no venting is just silly. Lots of soot settling everywhere, and fun combustion products to breath…and you don’t have enough BTUs to be letting in much fresh air. ---
**Author:** ![Hampshire](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hampshire/32/4887_2.png) [@Hampshire](https://boards.straightdope.com/u/Hampshire)\ **Post date:** [February 2, 2014, 4:17am UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/29 "2014-02-02T04:17:54Z")
> [@Charlie\_Wayne](#): > > So, I am curious why would so many people upload these videos to promote this method? To my mind, it just doesn’t add up. > > Would anyone have any explanation for this? Why are there so many youtube videos showing how to make mountain dew glow in the dark with hydrogen peroxide? (FYI- It doesn’t) Youtube and Facebook have become the newest vehicles for spreading modern urban legends. ---
**Author:** ![Rhythmdvl](https://avatars.discourse-cdn.com/v4/letter/r/85f322/32.png) [@Rhythmdvl](https://boards.straightdope.com/u/Rhythmdvl)\ **Post date:** [February 2, 2014, 4:33am UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/30 "2014-02-02T04:33:53Z")
As an aside, wouldnt a listed kerosene heater be a better choice for emergency heating? ---
**Author:** ![Guinastasia](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/guinastasia/32/5751_2.png) [@Guinastasia](https://boards.straightdope.com/u/Guinastasia)\ **Post date:** [February 2, 2014, 5:19am UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/31 "2014-02-02T05:19:55Z")
> [@Charlie\_Wayne](#): > > My intuition tells me that you are correct. > > Thing is … there are so many videos from seemingly diff people who say they have gotten this thing to work. > > Would it really be worth the money for a company selling this device for $40 to recruit all these people to falsely claim this thing works wonder for them? > > My main interest is emergency heating in the event of a power failure. > > I have trouble believing there are hundreds of thousands of people who would jump to buy one of these products when their goal is just to reduce the cost of heating one room. > > Besides, most of these videos show people how to do it for themselves and are not trying to sell this $40 product. > > So, I am curious why would so many people upload these videos to promote this method? To my mind, it just doesn’t add up. > > Would anyone have any explanation for this? My explanation? To put it bluntly, people are stupid. Some of them may have convinced themselves it works, just like some people really believe that homeopathic medicine helps their headaches. Also, while these people aren’t selling them, they may have friends who are, and are trying to shill for them. ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [February 2, 2014, 5:25am UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/32 "2014-02-02T05:25:54Z")
There’s a lot of videos by different people about a mysterious hum that has appeared all over the world. Except that the “mysterious hum” has been traced to a specific movie, and it’s the exact same sound effect from the exact same movie in all of the videos. So it’s not really a bunch of different people. The candle thing could be similar. If you want to heat a room (at least around here in Pennsylvania) you multiply the length, width, and height of the room to get its volume in cubic feet. Then you multiply that by a number between 3 and 10. 3 is for the best, modern, well insulated room out there and 10 is basically a barn. This will give you the BTUs you need to adequately heat that room. So for a typical 10x10 room with an 8 foot ceiling, you’d need 10x10x8x6 = 4800 BTUs. So a “Mr. Heater Portable Buddy Propane Heater” (the first heater that showed up on my very quick google search - I otherwise haven’t even heard of this model before) would be able to heat this size room since it does up to 9,000 BTU. Figure maybe 50 BTU for one of those little candles and you’ll need 96 candles to heat the room adequately. Now candles do vary quite a bit in their heat output, and larger candles could easily be double that, but anyone who tells you they can heat up an entire room with only 4 candles isn’t even in the right ballpark. Adding pots and nuts and bolts and whatever other silliness you want to add doesn’t increase the heat any. All it does is change how quickly it goes from the flame to the air around it. An open flame like a candle is going to heat the air above it in a column very quickly, so most of the heat will rise towards the ceiling. Putting items above the candle’s flame to store the heat and release it more slowly out to the air will make the heat spread out more evenly into the room but it won’t change how much heat total you need to heat the room. If you buy those little tea candles in bulk, you can get 100 of them for about 10 bucks. Walmart claims they will burn for about 4 to 5 hours. You need pretty close to the entire package every 5 hours or roughly 5 packs of those a day to heat your room. That’s about $50 per day on heat. Now if you heat a much smaller room, say 7x7 or 6x8, maybe you can get by on half of that in candles, or only $25 per day. I’m thinking electric heat is going to be a wee bit less expensive than that. ---
**Author:** ![Charlie\_Wayne](https://avatars.discourse-cdn.com/v4/letter/c/4bbf92/32.png) [@Charlie\_Wayne](https://boards.straightdope.com/u/Charlie_Wayne)\ **Post date:** [February 2, 2014, 5:39am UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/33 "2014-02-02T05:39:34Z")
> [@engineer\_comp\_geek](#): > > If you buy those little tea candles in bulk, you can get 100 of them for about 10 bucks. Walmart claims they will burn for about 4 to 5 hours. You need pretty close to the entire package every 5 hours or roughly 5 packs of those a day to heat your room. That’s about $50 per day on heat. I bought 140 for $6.50. Perhaps they come in diff sizes. The ones I bought are fairly small but each one burns for 4 hours. I don’t follow your math. Even if you use 4 candles, that means you would use 24 candles in 24 hours. 140 candles would last for about 6 days. Seems like $1 per day to me. ---
**Author:** ![Charlie\_Wayne](https://avatars.discourse-cdn.com/v4/letter/c/4bbf92/32.png) [@Charlie\_Wayne](https://boards.straightdope.com/u/Charlie_Wayne)\ **Post date:** [February 2, 2014, 5:46am UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/34 "2014-02-02T05:46:45Z")
> [@Guinastasia](#): > > My explanation? To put it bluntly, people are stupid. Some of them may have convinced themselves it works, just like some people really believe that homeopathic medicine helps their headaches. > Also, while these people aren’t selling them, they may have friends who are, and are trying to shill for them. I would guess that it’s probably just a very small number of people who get many free email accounts. They only need a few friends or relatives to appear on the youtube videos. But in many cases, one person could promote something by using many diff email accounts. I’m still largely undecided. All I want this thing for is to produce enough heat when there is a power outage that I could stay in my apartment dressed in several layers of winter clothing. I still can’t figure out just how much heat they will produce in my apartment when there is no electric heat. I guess I will have to do an experiment in my smallest room - either a bedroom or a large closet. My biggest problem in the power outage was that I would just get too cold at night when sleeping. But if I could figure out a way to place one in my largest closet and do it without any risk of fire, I would be happy to spend 10 hours a day sleeping in the closet if it was not too cold. I’d probably use another two during the day. But the good thing is that I would only need to use one set at a time. The cost is not a big concern for me. I just want to know that I could stay in my apartment and prepare some kind of meals and last through a power failure. ---
**Author:** ![Charlie\_Wayne](https://avatars.discourse-cdn.com/v4/letter/c/4bbf92/32.png) [@Charlie\_Wayne](https://boards.straightdope.com/u/Charlie_Wayne)\ **Post date:** [February 2, 2014, 9:54am UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/35 "2014-02-02T09:54:47Z")
> [@Charlie\_Wayne](#): > > I bought 140 for $6.50. Perhaps they come in diff sizes. The ones I bought are fairly small but each one burns for 4 hours. > > I don’t follow your math. Even if you use 4 candles, that means you would use 24 candles in 24 hours. 140 candles would last for about 6 days. > > Seems like $1 per day to me. To clarify, I bought a package of 140 tealights for $6.50. Each one is very small. One of them weighs 9.7 gram (in case that may help anyone compare these tealights to a differnt kind). I’m not certain that one of them will burn for 4 hours. That is just what the sales clerk at the store told me. If you construct one of these heaters and it uses 4 tealights that burn for 4 hours, that means that in a 24 hour period you would need to burn 24 tealights. But I have one burning now and I will let it burn out to find out just how long it will really burn. That equates to one package lasting for 6 days and the cost would be $6.50 for 6 days or about $1.10 per day. I fully admit that seems very unlikely. ---
**Author:** ![Cheesesteak](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cheesesteak/32/3694_2.png) [@Cheesesteak](https://boards.straightdope.com/u/Cheesesteak)\ **Post date:** [February 2, 2014, 10:56am UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/36 "2014-02-02T10:56:21Z")
> [@Charlie\_Wayne](#): > > My biggest problem in the power outage was that I would just get too cold at night when sleeping. But if I could figure out a way to place one in my largest closet and do it without any risk of fire, I would be happy to spend 10 hours a day sleeping in the closet if it was not too cold. I have two suggestions to get you away from this silly and dangerous tealight design. [a proper indoor emergency heater.](http://www.walmart.com/ip/Mr.-Heater-6-000-12-000-and-18-000-BTU-Cabinet-Radiant-Propane-Heater/21714347) [a way to sleep warm](http://www.walmart.com/ip/Everest-Mummy-5F-15C-Degree-Sleeping-Bag/2581360) A couple of other statements, 4 tealights do not generate enough energy to appreciably warm a room. You can’t run them 24 hours because you shouldn’t have candles burning when you’re not home and when you’re sleeping. ---
**Author:** ![Charlie\_Wayne](https://avatars.discourse-cdn.com/v4/letter/c/4bbf92/32.png) [@Charlie\_Wayne](https://boards.straightdope.com/u/Charlie_Wayne)\ **Post date:** [February 2, 2014, 1:14pm UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/37 "2014-02-02T13:14:00Z")
After testing the tealights I bought, I found they will burn for 3.5 hours. ---
**Author:** ![Charlie\_Wayne](https://avatars.discourse-cdn.com/v4/letter/c/4bbf92/32.png) [@Charlie\_Wayne](https://boards.straightdope.com/u/Charlie_Wayne)\ **Post date:** [February 2, 2014, 1:18pm UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/38 "2014-02-02T13:18:53Z")
> [@Cheesesteak](#): > > I have two suggestions to get you away from this silly and dangerous tealight design. > > [a proper indoor emergency heater.](http://www.walmart.com/ip/Mr.-Heater-6-000-12-000-and-18-000-BTU-Cabinet-Radiant-Propane-Heater/21714347) > > [a way to sleep warm](http://www.walmart.com/ip/Everest-Mummy-5F-15C-Degree-Sleeping-Bag/2581360) > > A couple of other statements, 4 tealights do not generate enough energy to appreciably warm a room. You can’t run them 24 hours because you shouldn’t have candles burning when you’re not home and when you’re sleeping. Thank you for your suggestions. Unfortunately, as far as I can tell, all the indoor emergency heaters shown on your link require electricity to work and my goal is to be able to heat my apartment when there is a power failure. The sleeping bags look interesting and they sure are a good alternative to sleeping in several layers of winter clothing under several blankets. But when the temperature outside is minus 20 degrees and there is no heat in your home, I would guess the inside temperature would fall very close to the outdoor temps. Would you be able to survive sleeping at night in one of those sleeping bags? I suppose that in case of emergency, a good sleeping bag would be a good choice. But would it prevent you from getting sick during very low winter temperatures? One of the best quality sleeping bags listed is rated at: -15C and 5F. But the outdoor temperature can fall seriously lower than that. ---
**Author:** ![MandaJo](https://avatars.discourse-cdn.com/v4/letter/m/ac91a4/32.png) [@MandaJo](https://boards.straightdope.com/u/MandaJo)\ **Post date:** [February 2, 2014, 1:24pm UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/39 "2014-02-02T13:24:31Z")
The heater he linked to runs on propane, not electricity. ---
**Author:** ![Fuzzy\_Dunlop](https://avatars.discourse-cdn.com/v4/letter/f/848f3c/32.png) [@Fuzzy\_Dunlop](https://boards.straightdope.com/u/Fuzzy_Dunlop)\ **Post date:** [February 2, 2014, 2:49pm UTC](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271/40 "2014-02-02T14:49:26Z")
> [@Charlie\_Wayne](#): > > I bought 140 for $6.50. Perhaps they come in diff sizes. The ones I bought are fairly small but each one burns for 4 hours. > > I don’t follow your math. Even if you use 4 candles, that means you would use 24 candles in 24 hours. 140 candles would last for about 6 days. > > Seems like $1 per day to me. If you use 4 candles your room won’t be heated. You need 96 candles to heat the room adequately. 140 candles would last less than 6 hours. [Previous page](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271.md?page=1) [Next page](https://boards.straightdope.com/t/does-a-heater-using-candles-and-flower-pots-really-work/680271.md?page=3)