How to Fix Candle Tunneling (and Why It Happens)

How to Fix Candle Tunneling (and Why It Happens)

Candle tunneling is one of the most common issues people run into when burning candles — and thankfully, it’s also one of the easiest to fix. At Wax & Warmth Candle Co., we test every batch of candles we make to ensure a clean, even burn, but sometimes a few simple care steps can make all the difference. Here’s what tunneling is, why it happens, and how to safely correct it without damaging your candle or container.

What Is Candle Tunneling?

Tunneling happens when only the wax around the wick melts, leaving a hard ring of unmelted wax along the sides of the jar. Over time, that leftover wax forms a tunnel down the center. This limits oxygen to the flame, weakens scent throw, and can shorten the total burn life of your candle.

Why Candle Tunneling Happens

There are a few common reasons tunneling occurs:

1. Blowing out the candle too soon on the first burn
   The first burn is the most important. Wax has what’s called a “memory,” so if you extinguish the flame before the melted wax reaches the edges, the candle will continue to burn in that narrow tunnel each time afterward.

2. Drafts or uneven airflow
   Burning near a window, vent, or fan can cause the flame to lean and heat one side more than the other, resulting in uneven melting.

3. Wick trimmed too short or not producing enough heat
   If the wick is trimmed below ¼ inch, it may not generate enough heat to form a full melt pool. Always keep your wick trimmed to about ¼ inch before each burn — not shorter, and not longer. A longer wick can create high flames, soot, or glass overheating.

4. Poor wax quality or formulation
   Low-grade wax blends often burn unevenly. At Wax & Warmth, we use a premium coconut-soy blend designed for a smooth, slow, even melt when properly cared for.

How to Safely Fix a Candle That’s Already Tunneling

If your candle has already developed a tunnel, don’t worry — it can usually be corrected with one of these safe methods:

1. Top-down candle warming lamp
   Place the candle under a top-down candle warming lamp for one to two hours until the entire surface has melted evenly. This gently evens the wax without exposing the glass to open flame or excessive heat. Avoid plate-style warmers that heat from the bottom, as they can melt the full candle and dislodge the wick.

2. Low-heat gun or hair dryer method
   Using a heat gun or hair dryer on a low setting, carefully warm the wax surface in circular motions from about six inches away until it levels out. Allow the wax to cool and harden before relighting.

3. Full burn reset
   Once the surface is even again, let the candle burn long enough for the melted wax to reach the jar’s edges — usually between two and four hours. This resets the candle’s “memory” and helps prevent tunneling from returning.

A note on aluminum foil “fixes”
You may have seen online tutorials that suggest wrapping the top of the jar with foil to trap heat. While this can work in metal containers, we strongly discourage using foil on glass candles. The reflective heat can cause the glass to overheat or crack, and it restricts airflow around the flame. The safer methods above achieve the same result without risk.

How to Prevent Candle Tunneling in the Future

• Allow the first burn to last long enough for the melted wax to reach all sides of the container.

• Keep the wick trimmed to about ¼ inch before each burn.

• Burn your candle for two to four hours at a time — long enough to form a full melt pool but not so long that the wick shifts.

• Keep your candle away from drafts or fans.

• Let it cool fully before relighting.

These simple steps will help your candle burn evenly, extend its total burn time, and maintain a stronger fragrance from start to finish.

Final Thoughts

Even the best candles can tunnel once in a while, but it’s easy to fix safely. With a little care, your Wax & Warmth candles will give you hours of clean, even fragrance and that warm glow that makes your space feel inviting.