Comparing candles with 2-wicks and 3-wicks
To burn efficiently, we want our candles to have a full melt pool. For larger containers, this means we need to use multiple wicks. Here are some pictures of a side-by-side comparison to help explain how 2-wick and 3-wick candles burn differently and whether or not 3 wicks are really necessary.
The 3-wick candle was purchased at a popular store and the 2-wick candle was made by me. The containers are the same diameter, though one is slightly taller than the other.
The 3-wick candle measures 3-15/16 inches in diameter.
The 2-wick candle measures 3-15/16 inches in diameter.
The 2-wick container (right) is slightly taller than the 3-wick container (left).
The 3-wick candle is made from a blend of paraffin and natural waxes and has a net weight of 14.5 ounces. The 2-wick candle is made from 100% soy wax and has a net weight of 16 oz. This is why the wax heights are different even though the containers are essentially the same size. To account for this, I marked the starting wax levels on the containers.
Starting wax levels were marked on the glass using a Sharpie.
When estimating the time it should take to create a full melt pool on a candle, we allow 1 hour for every inch of the container’s diameter. We essentially have a 4-inch diameter here, so we should have a full melt pool in 4 hours or less.
I took pictures of the candles during a 4 hour burn test. There are overhead shots of the melt pools at different time periods, so you can compare how quickly the candles were melting. The 3-wick candle had a full melt pool within the first hour. The 2-wick candle didn’t reach a full melt pool until sometime between 2 and 3 hours had gone by, but this is still within the 4 hour time estimate based on a 4-inch container diameter.
Before lighting the candles.
After burning for 1 hour. The 3-wick candle has a full melt pool. The 2-wick candle has a partial melt pool.
After burning for 2 hours. The 2-wick candle almost has a complete melt pool, with just a small amount of unmelted wax remaining at the top and bottom edges.
After burning for 3 hours. Both candles have a full melt pool.
Both candles were allowed to burn for the full 4 hours. Once the wax has melted all the way across, it has to start melting downwards. This made the melt pool on the 3-wick candle a lot deeper than the one on the 2-wick candle. This can cause the wicks to shift and possibly fall over if they are not properly secured to the bottom of the container. Also notice that the new wax level on the 3-wick candle is farther below its starting point that the 2-wick candle is.
After burning for 4 hours. The 3-wick candle (left) has a much deeper melt pool than the 2-wick candle (right).
In Part 1 of this series, we talked about how using more wicks released more scent. You can see that the 3-wick candle has more wax that was melted, so there would be a greater hot throw.
In Part 2 of this series, we learned that candles with more wicks burn faster. Look at the difference between where the wax level is now compared to where it was before the candles were lit. The 3-wick candle level dropped more than the 2-wick level did, which means more wax was burned off during the same amount of time.
So what’s the verdict? It depends on what your goal is. Do you want a candle that lasts longer because it burns slower or one that gives off more scent because it burns faster? There’s no right or wrong answer! Both candles had full melt pools within the expected time limit, showing that a container this size doesn’t need 3 wicks to burn efficiently if the wicks are the proper size. It also showed that this sized container can hold more wax than the popular store-brand used, so they are skimping out!
Now you have seen for yourself why larger containers require multiple wicks and that the more wicks a candle has, the faster it will burn. This explains why our 16 oz candles (2 wicks) burn for roughly the same amount of time as our 9 oz candles (1 wick). Just remember that if the 2 candles you’re deciding between are the same size, the one with more wicks may not always be the best choice.
For more information on what wicks are and why some candles have multiple wicks, see The World of Wicks Parts 1 and 2.