Candle tunneling happens when a candle burns down the middle but leaves unburned wax around the edges. This usually occurs if the candle isn’t burned long enough on the first use or if the wick is too small for the container. To fix it, wrap foil around the top, melt the top with a heat gun or hairdryer, or change the wick if needed.

You need to act quick to avoid wasting any wax!  The longer you wait, the harder it becomes to fix. There are two main ways to stop candle tunneling after it starts:

• The aluminum foil trick
• Heat gun or hair dryer leveling

How to prevent candle tunneling

There are two main strategies for preventing tunneling from happening.

Burn the candle for at least 3 hours

Not a hard and fast rule, but you want to make sure the candle has time to start melting.  If it burns too deep before melting anything else, the flame won’t have the opportunity to properly melt the surface and it will become a problem.

Make sure you allow the candle to burn for at least 3 to 4 hours in its first few “sessions.”

If you don’t let it burn long enough, wax memory will remain small and your candle will probably start tunneling.

Use the right wick size

If you’re a candle maker, make sure you’re testing your candles to choose the right wick size and series for your wax and container.

Tunneling means you have to increase the size of your wick.  This typically addresses undersized wick problems. There are many testing tricks for candles to quickly find the right wick size.

How to fix candle tunneling

Before doing anything make sure tunneling is the real problem.  Some candles that look like they’re tunneling are actually suffering from craters. You can tell it’s craters if the wick disappears minutes after burning or the width of the melted area is really small.

Tunneling usually has wide, clean circle around the outside of the wick like the image below:

The tinfoil method

When your candle has the right size wick but you ended up with tunneling because you didn’t burn it long enough it’s time to move to more… creatively aggressive maneuvers.

Melt the “shelf” of wax with heat from the candle by redirecting that heat BACK to the wax instead of out of the container using tinfoil. Here’s how:

1. Before lighting the candle, trim the wick down to a 1/4″ height.
2. Cover the top of the candle with tinfoil (aluminum foil).
3. Cut an opening on the top roughly 1″ wide, or small enough that tinfoil remains above the wax shelf.
4. Carefully light the candle and allow it to burn for 3-4 hours.

You may need to repeat this a few times to completely restore the candle.

The heat gun method

Alternatively, you can melt the surface of the candle down with a heat gun or hair dryer to level out the top.  This requires no tinfoil and works much faster.

Evenly melt the top 1/8″ – 1/4″ of candle wax and then allow to harden for 4-6 hours before burning the candle again. If the wick is still below the wax level, remove the melted wax with a spoon before allowing the candle to rest.

If tunneling continues, or the wick is covered up, proceed to the next option.

The wick replacement method

If your wick is swallowed up in wax, or the tunneling is far too tall to be corrected using any of the earlier methods, your only option is to replace the wick completely.

Gather the following equipment:

• New wick
• Oven (or heat gun, as shown)
• Apple corer

You can usually buy wicks from your local hobby store, though there’s no guarantee they’ll be the right size for your candle.  Apple corers are easy to find in a grocery store.

1. Push the apple corer through the wax around the wick.
2. Twist apple corer and carefully pull upwards until the wax plug comes out with the wick. If the wick is still stuck to the bottom of the candle jar, use a needle nose pliers to pull out the wick tab and wick.
3. Throw the old wick away.  Keep as much wax as possible.
4. Place wax back in the empty area of the candle. Don’t worry about this being perfect – you’re just going to melt all the wax down again anyways.
5. With a heat gun, melt the surface of the candle until the entire surface is liquid and it appears flat. Alternatively, place the container in the oven on low (usually about 200°F or 93°C) for 20 minutes or until the entire surface of the candle is liquid and appears flat.
6. After the surface has dried, use a toothpick or skewer to make a hole for the replacement wick. You may have to cut off the wick tab if the wick is too long

Don’t worry about gaps between the wick and the wax. After the candle is re-lit, the areas will fill back in with liquid wax right away.

Since your replacement wick doesn’t have a tab, it may eventually tip over when the candle reaches the end of its life. Typically this doesn’t take much time off the life of the candle, but it’s better than never burning the candle again!

Enjoy burning your candle!