Can Candle Wax Get Too Hot?
Candles create a warm glow and pleasant fragrance that can instantly make a space feel more inviting. But as the wax melts and the candle burns, it’s important to pay attention to the temperature of the melted wax. If the wax gets too hot, it can lead to issues like soot buildup, tunneling, and even become a potential fire hazard.
In this article, we’ll take a deeper look at how hot is too hot when it comes to candle wax. We’ll cover the ideal temperature range, signs of overheating, and simple tips to prevent your candle wax from getting dangerously hot.
What is Candle Wax?
Candle wax is made up of hydrocarbons, which are organic compounds containing only hydrogen and carbon atoms. There are three main types of wax used in candle making:
Paraffin Wax – Derived from petroleum, coal or oil shale, paraffin wax is a byproduct of the distillation process that produces gasoline. It consists mainly of straight chain alkanes such as octadecane and nonadecane with the chemical formula CnH2n+2. Paraffin wax is commonly used in candle making due to its low cost and ability to hold fragrances.1
Soy Wax – Made from hydrogenated soybean oil, soy wax is composed of fatty acids and fatty alcohols. It is a sustainable, renewable resource since it comes from plants. Soy wax burns cooler than paraffin, requires less frequent trimming of the wick and allows more fragrance throw.2
Beeswax – Secreted by honey bees, beeswax is made up of esters of fatty acids and various long-chain alcohols. It has a natural honey aroma and color. Beeswax candles burn brighter and longer compared to paraffin and soy.3
Melting Points of Candle Waxes
Different types of candle wax have different melting points. Paraffin wax, which is derived from petroleum, has a melting point range between 115-150°F (Which Temperature Does Candle Wax Melt? Complete list of …). Soy wax melts between 115-165°F, with some specialty soy waxes formulated to melt at lower temperatures like 130°F (Melting Point Factors for Common Waxes). Beeswax has the highest melting point at 144-147°F. Knowing the melting point of the specific wax being used in a candle is important to understand at what temperatures the wax may become too hot.
Ideal Burning Temperature
The ideal burning temperature for candle wax varies depending on the type of wax used. Paraffin wax, a common candlemaking material, has a melting point between 115-150°F (Source: https://en.wikipedia.org/wiki/Candle). For paraffin candles, an ideal burning temperature is between 180-200°F. This allows the wax to liquefy into a pool while avoiding overheating that can cause issues like soot and smoking (Source: https://www.harlemcandlecompany.com/blogs/journal/how-hot-does-a-candle-get-how-to-avoid-getting-burned).
Higher melting point waxes like beeswax (144-147°F) and soy wax (135-145°F) can handle slightly higher temperatures of 200-220°F before overheating occurs. The advantage of a lower ideal temperature for paraffin is a larger melt pool that provides more fragrance. The tradeoff is paraffin requires more care to avoid soot and smoking. Higher melt point waxes can withstand higher heat but may not liquefy as readily.
Finding the right burning temperature helps maximize melt pool size while avoiding issues like tunneling, poor fragrance throw, and smoking. Monitoring wax appearance, melt pool diameter, and other signs can help determine the ideal range for a particular candle.
Overheating Wax
Overheating wax can alter its chemical structure and cause a number of issues. According to candlemaking forums, overheated wax may turn yellow or brown, lose its scent throw, become brittle or crumbly, develop frosting or sweating, or separate into waxy and oily layers [1]. This happens because the high heat damages the wax molecules.
Wax can actually combust if exposed to temperatures over 400°F for an extended period, according to experts on Quora. This is known as “flash point” – the lowest temperature at which vapors from wax can ignite [2]. So it’s important to avoid severely overheating wax, as it becomes a fire hazard.
The ideal temperature range for burning wax is 120-170°F, though this varies by wax type. Exceeding 200°F can start altering the wax’s properties. Soy wax in particular should not exceed 185°F during production according to candle making sites [3]. In summary, overheating damages wax and can create safety issues if taken to extremes.
Preventing Overheating
There are several tips candle makers can follow to avoid overheating wax:
- Use a double boiler or makeshift double boiler instead of a microwave when melting wax. This allows for more controlled, even heating without hot spots that can scorch the wax (1).
- Stir melted wax frequently to distribute heat evenly and prevent the bottom from overheating. Pay special attention when adding new wax chunks to the melt pool (2).
- Keep melted wax over low heat. Higher temperatures can burn components like fragrance and cause the wax to discolor (3).
- Do not leave melting wax unattended. Monitor the temperature and adjust the heat source as needed (1).
- Allow enough time for complete melting without rushing the process. Melting too rapidly can overheat areas before dispersing (2).
- Maintain a 6-10 inch gap between wax melters and heat sources. This prevents direct contact that could lead to overheating (1).
Following these simple guidelines when melting wax can prevent overheating and lead to higher quality finished candles.
(1) https://www.powerblanket.com/blog/4-ways-beautiful-candles-heating-wax-effectively/
(2) https://nzcandlesupplies.nz/blogs/news/soy-wax-troubleshooting
(3) https://www.quora.com/What-happens-if-you-overheat-candle-wax
Signs of Overheated Wax
One of the most common signs that wax has been overheated is a change in the color of the wax. According to candle making forums, overheated wax can turn a darker color or take on a scorched appearance (https://www.quora.com/What-happens-if-you-overheat-candle-wax). The discoloration is especially noticeable in lighter colored waxes like soy wax. Overheating can also cause wax to lose its opacity and become more translucent.
In addition to color changes, overheated wax may develop a burnt plastic-like smell according to posts on Reddit (https://www.reddit.com/r/candlemaking/comments/16ovtji/can_you_overheat_wax/). This is often accompanied by smoke coming off the wax if it gets extremely hot. The burnt odor can linger even after the candle has cooled and hardened.
Excessive bubbling while the wax is melting can be another red flag, as described by New Zealand Candle Supplies (https://nzcandlesupplies.nz/blogs/news/soy-wax-troubleshooting). Normal melting should not cause the wax to boil rapidly or foam up. If the wax appears to be bubbling and frothing, it’s a sign that the temperature is too high.
Finally, separation of wax and fragrance oil after cooling and hardening indicates the wax was overheated. The oils may “sweat out” and emerge on the surface of the cooled candle, rather than staying blended throughout the wax. This can lead to issues with burning and scent throw. Checking for oil separation by cutting into the cooled candle can confirm if overheating occurred.
Safety Precautions
When candles are burned too hot, the wax can reach temperatures over 250°F (121°C), which poses several potential dangers. One risk is that the wax can catch fire if it gets hot enough, causing the flame to flare up and potentially spread (Source). Overheated wax can also release more scented chemicals and soot into the air, creating indoor air pollution.
Additionally, hot wax can cause severe burns if it comes in contact with skin. Wax temperatures over 160°F (71°C) can cause third degree burns in just one second of contact. The National Fire Protection Association states that over 1,500 home fires per year are started by candles, often due to combustible items being placed too close to them.
To prevent candle wax from overheating, make sure to trim wicks to 1⁄4 inch before lighting, keep wicks centered in the melted wax pool, and extinguish candles once there is less than 2 inches of wax remaining. Candles should also be kept away from drafts and flammable materials. By taking safety precautions, the risks of overheated wax can be minimized.
When to Trim or Extinguish
The flame on a candle should not get so high that it is curling over the edges and flooding the wax pool. According to Malibu Apothecary, it is recommend to not burn a candle for more than 4-5 hours at a time before extinguishing it https://malibuapothecary.com/blogs/clean-candles/candle-care-101. Allowing the wax pool to get too deep can lead to issues like tunneling. If you notice the flame is getting too tall and starting to rapidly melt down the sides, it is time to extinguish the candle.
You can extinguish the candle by gently blowing it out or using a candle snuffer. Avoid letting the flame go unattended if it is clearly getting too high. The wax can get so hot that it combusts if the flame height is uncontrolled. It is also important to trim the wick before relighting if it has gotten too long and caused a big flame. This will help prevent the problem from recurring. A good rule of thumb is to extinguish and trim the wick if the flame starts to curl and blacken the wax pool edges.
Conclusion
Candle wax can become dangerously hot if overheated, so it’s important to monitor the wax temperature. The ideal burning temperature for most candle waxes is between 120-150°F. Exceeding 185°F puts candle wax at risk of igniting. Overheated wax may smoke, discolor, lose its scent, or create bubbles. To prevent overheating, avoid burning candles for over 4 hours at a time, or use candle heat protectors. Always trim wicks to 1⁄4” before lighting, and extinguish candles if the wax pool reaches the edges. In summary, staying within the proper wax temperature range keeps candles burning safely and optimally.