Candle tunneling can happen to any candle when a small portion of wax around the wick melts leaving the walls of the container with non melted wax durning a burn.
It will appear as though the flame is burrowing into the candle and creating what resembles a small, vertical tunnel hence the name.
Inside the tunnel, the wax directly underneath the flame quickly melts into liquid while the surrounding wax remains hard. This causes the tunneling to become worse over time.
Once the wick descends deeper into the surrounding wax, the flame won’t be able to get enough oxygen to sustain itself, causing the candle to go out.
Normally, burn time is based on the total volume of wax in the container — in general, bigger candles have longer burn times. But when candle tunneling happens, only a fraction of the wax is actually used up before the wick reaches the bottom.
HOW TO FIX CANDLE TUNNELING
What should you do if your candle has already started tunneling?
Don’t worry, you can still save it! By understanding what causes tunneling, you can naturally reverse the situation and save your candle. In order to fix candle tunneling, all you need to do is melt the outer wax surrounding the tunnel and make the surface even again.
We recommend 2 ways to do this:
OPTION 1: THE HAIR DRYER METHOD
- Trim the wick and remove any debris inside the tunnel.
- Using a heat gun (if you have one) or hair dryer on the highest setting, heat the wax on the top surface of the candle.
- You can carefully poke at the unmelted wax on the sides with a toothpick to help it melt faster.
- Continue heating until the entire top surface of wax has completely melted and smoothed over.
- Relight your candle and allow it to burn for at least 30 minutes or until you can no longer see any tunneling.
- Set your candle aside and let the wax harden over the next few hours. Depending on the type of wax used in your candle, it can take between a couple to a few hours to reach full hardness.
OPTION 2: THE ALUMINUM FOIL CHIMNEY METHOD
- Trim the wick and remove any debris inside the tunnel.
- Cover the top of the candle with aluminum foil.
- Cut a small opening (around 1-inch) in the center of the aluminum foil.
- Remove the aluminum foil, light the wick, then place the foil cover back on.
- Allow the candle to burn for a few hours until the top surface of wax has completely melted and smoothed over.
- Set your candle aside and let the wax harden over the next few hours to reach full hardness (see above).
HOW TO PREVENT TUNNELING WHEN BURNING YOUR CANDLES
To prevent tunneling, all you need to do is burn your candle long enough each time so that the entire top surface of wax is melted. This is especially important the first time you burn your candle!
How long that takes depends mostly on the size of the candle. A good rule of thumb to remember is that you should burn your candle for one hour per every inch of its diameter. So if your candle has a diameter of 3 inches, you should plan to let it burn for 3 hours before putting it out.
And that's it! We hope this guide to fixing and preventing candle tunneling will help you enjoy candles that last longer and burn more beautifully.