Survival Gardening

# DIY Survival Air Heater! 300w/450w of heat! uses NO electricity! cooks too! clay/brick radiant heat!

DIY radiant clay pot and brick heater! DIY Non-electric Space Heater! full build & temp tests included! video shows the unit heating up a small room. full details listed below…

THE POWER OF CANDLES: Small candles produce an average of 32-45 watts of heat. (regular ones 40-80 watts). this unit uses 9 or 10 to generate anywhere from 288 to 450 watts of heat! the unit itself reaches over 400F (459F maximum recorded).

HOW IT WORKS: the pots/bricks absorb the thermal energy of the candles then re-radiate it back (slowly and evenly) into the surrounding living space. the thermal mass of the pots and bricks is used because they store and re-distribute the heat into the living space. heat from the candles alone (with no thermal mass surrounding them) just rises quickly to the ceiling where it’s not felt (unless you’re living in the attic).

unit easily heated the 6’x10′ (*60 sq. ft.) area in the front part of my house where i conducted the testing (see temps in video). just place the unit near you and you’re set! *after an hour of being right next to it, {when filming}, i was sweating and used an ‘ice-pak’ on my face to cool down {seen in video on table}. note that 300-450 watts is about one-half to one-third the power of a full-size electric room heater but this one gets the job done in smaller areas or if you are close to it. general ‘rule of thumb’ is 10 watts per square foot (but can be as little as 5 watts) if the air being heated is just cool (not super cold).

VERY EASY TO MAKE! it’s just 3 bricks 3 pots and 9/10 candles. that’s it! (50 packs at walmart were only \$2.77 at time of filming). step one: set the 3 bricks on a table as shown. step two: place the 9 or 10 candles in the chamber. step 3: set each of the 3 pots (one at a time) onto the top edge of the brick chamber (as shown). (two 6″ pots and one 8″ pot). use only non-painted and non-glazed clay pots. leave holes open so air can flow freely. (for good convective heat transfer). this allows the candles to pull air in from the sides producing an updraft under the pots so they burn strong.

IT COOKS TOO! if you want to see how to use this as a stove burner for cooking, make sure to watch the whole video. that footage really shows the full power of this unit. (cooks like an electric stove burner on high). tip on the cooking. use thin steel pans for best results.

USAGE: great for power outage, emergencies, camping, general ‘off-gridding’ or everyday use.

HEATING TIMES: unit produces some heat within 5 minutes, full heat in 30-45 minutes (and blazing hot in 60 mins). once the clay pots are hot i use thick gloves to pick them up or to move them. tea lights burn on average for 3 to 5 hours.

A FINAL THOUGHT – i’ve noticed lately that this type of heater is getting a ‘bad wrap’. it’s become popular to say that candle heaters ‘don’t work’… but in fact, they do work (otherwise i wouldn’t break out in a sweat every time i sit near one). remember; even a small candle on the low-end produces 30w of heat. use 10, add thermal mass and you’ve got (at minimum) a 300w heater.

The bottom line: if you design your unit properly so that the candles burn strong, have the proper ‘candle to thermal mass’ ratio and are made with an appropriate type of thermal mass they work very well. an understanding how much ‘thermal energy’ is generated by different types of candles (and using the right number of them) is the key. knowing this tells you approximately how much heat the unit will generate and that allows for an estimate of how big an area the unit will cover. just figure 30 to 45 watts of heat for small candles and 40 to 80 watts for standard size ones. a lot depends on the length of the wick too (size of the flame). the size of the candle itself is not that important. bigger candles with more wax will burn longer but not necessarily any hotter than the small ones.
note: it’s easy to add longer wicks to smaller candles and tea-lights for a stronger burn. might be a future video?