In mid-July 2022 we reported . So at a time when it was a little warmer for us due to the weather. According to various media reports, including us, the tealight oven became a really “hot” topic on social media. After various fire stations took up the topic and a video was posted on this topic, Facebook and co.
The fire brigade's video
A video from the fire department showed how quickly a tea light stove can catch fire if more than two candles are used. Since the detail - too many candles - was not addressed, the fire department was accused of reporting in a completely undifferentiated manner. Many users therefore got the impression that a tea light oven represents a great danger. We also covered this video, but have now decided to remove it.
The fact is: a tea light oven is a danger if it has not been assembled properly, as well as if you put too many candles too close together.
At this point we would like to point out again: The tea light oven does not replace space heating, but is still useful. Even a hairdryer, an oven or an iron would perform poorly if you tried to heat a room or even the entire house, but these devices still make sense if you use them for what they were originally invented for and were thought.
So: tea light oven > Hot or not?
What does it come down to in the end?
It depends on the way you use a tea light oven or how you use it.
It is important to note:
- Is it a self-made tea light oven product or a tested original product?
- Will it be used for its original purpose of additional heat source or as a space heater?
- Are the tea lights themselves used correctly using the respective manufacturer's safety instructions? (on every candle package it says, among other things, that the candles must not be placed too close together) Even without a clay pot as a fireplace and heat storage, a so-called tea light burn or wax burn can occur.
Tealight oven FAQ – How dangerous is a tealight oven? What is a wax burn and how does it occur?
After the media reports, an expert spoke to us. After a lively exchange of information, we would like to provide the following information at this point:
What is a tea light oven actually about?
The tea light oven is about storing and converting heat. The convection heat from the tea lights is converted into radiant heat on the clay vessel and made more usable by humans. The storage of heat in an “open fire” area is a complex topic.
As always, when lighting an open fire in the living area, there are a few things that should be taken into account to ensure that it does not become dangerous. If you overdo it with heat retention, you can cause a wax burn (also known as candle burn or tea light burn), which can no longer be extinguished with water! It is important: Always follow the associated safety instructions and information!
When building a tealight oven yourself, it can happen that the entire tealight oven suddenly smokes or catches fire.
- How can this happen?
- Will the clay pot catch fire if it gets too warm or too dry?
- Or are there other reasons?
Depending on the use, clay is usually fired between 500 °C and 1,280 °C. In any case, the heat from the tea lights cannot cause any damage to the clay or ignite it.
In physics there is something called the auto-ignition temperature or ignition point. This means that a combustible substance will ignite spontaneously at this temperature and start burning if there is enough oxygen. The process is also called an exothermic oxidation reaction.
Liquid candle wax can ignite by itself above a certain temperature and, like a grease fire, can no longer be extinguished with water because the burning wax has a temperature of several hundred degrees, far above the boiling point of water at 100 °C and it burns through The extremely high temperature difference between water and oil would lead to an explosive (exothermic) combustion with a meter-high flame. (fat explosion)
Candles are made of different materials and therefore have different ignition temperatures. Organic tea lights, for example, often consist largely of rapeseed oil. The self-ignition temperature of rapeseed oil is around 250 – 300 °C. This means that in this example the temperature (in the inner pot) of 250 to 300 °C must under no circumstances be reached, which is also possible by observing the 10 important safety instructions.
For a better illustration, a video on the topic of tea light burning
It shows the creation of a tealight fire and various fire tests with tealights in a fire laboratory are shown.
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From the video you can see that you should take the topic of tea light burning seriously and would rather use several small, tested tea light ovens with 2 tea lights than light too many tea lights too close together.
This does not mean that this variant is the only safe construction and that there cannot be other variants. This is the variant that was chosen in collaboration with the fire department and which has also proven itself in many practical tests.
Always remember:
- Never leave open flames (candles, etc.) unattended in living spaces.
- Do not simply place more tea lights or other candles in your tea light oven, otherwise there is a risk of a dangerous wax fire.
- Never operate your tea light oven near easily combustible materials such as curtains, decorations, wood or flammable materials.
- If you use several tea light ovens in one room at the same time, please always remember to ventilate more often.
Information from the expert based on experience and customer feedback:
Relative temperature perception: If you place the tealight oven on the table in front of you, you can turn down the large room heater by, for example, 2 degrees, warmed by the direct radiant heat. With current heating costs, 2 degrees makes a big difference. In biology there is something called relative temperature sensitivity. If a person feels warm because they are sitting in front of the tea light stove and receive the radiant heat directly, then, depending on how they feel, it may be that they are really warm (campfire effect) and they suddenly no longer need as much room heat from the central heating as without it Tea light oven.
Conclusion:
A tealight oven like this can definitely be fun to make and you can also warm your hands a little at the table. However, the design is not suitable as a heater for an entire room.
This also applies to charcoal or gas grills, which should never be used in the room! The purpose of a tea light oven is not to heat a room, but to provide localized heat ( e.g. in the event of a heating failure). You also have to keep the distance between the candles and one another. And above all: like any open fire, a tealight oven must not be operated unattended.
Many thanks at this point to Christopher Willer from the Kreativ-Bastelstube for the support and information
Sources on the topic of temperature sensitivity
Wikipedia: Perceived temperature
textbook BioHeft 4
Human perception of temperature
Notes:
1) This content reflects the current state of affairs at the time of publication. The reproduction of individual images, screenshots, embeds or video sequences serves to discuss the topic. 2) Individual contributions were created through the use of machine assistance and were carefully checked by the Mimikama editorial team before publication. ( Reason )