I Reformulated My Signature Fragrance Blend and the Previously Approved Wick No Longer Works — Which Parts of Fragrance Composition Could Have Changed the Burn?

Your wick was approved for the old formula, not the name

You adjusted your house blend, perhaps to warm it up, to answer customer feedback, or because one component became expensive. The new version smells better to you and keeps the same product name. Yet the wick that burned it cleanly for months now struggles: carbon forms sooner, the flame looks different, or the melt pool no longer behaves as it did. You have not touched the wax or the jar. What changed is the fuel, and the aim of this page is to work out which part of the reformulation is responsible so you can fix that part rather than the whole candle.

A blend is a mixture of mixtures. Each component oil is already a composition of top, middle and base materials. When you change the proportions of the components, you change the overall balance of volatile and heavy materials reaching the wick, even if the total load stays at exactly the same percentage.

Four parts of a reformulation that can move the burn

1. The share of heavy base materials

Adding or increasing a component rich in resins, woods, vanillin or other slow-evaporating materials shifts the blend towards heavier fuel. The wick may then collect carbon faster or fail to keep up. This is the most frequent reason a reformulated gourmand or warm blend stops agreeing with its old wick.

2. The share of volatile top notes

Reducing a bright citrus or herbal component removes some of the quickest-evaporating material. That can make the blend feel softer in the room and can also change how lively the flame is. Makers often reduce a top note for smell reasons and then wonder why the burn changed.

3. The effective total load

Reformulating is a common moment for load to drift. If you added a new component on top of the old recipe instead of within it, the total percentage rose. Always recalculate the whole blend against total candle weight when the recipe changes.

4. A component with very different handling properties

If the new component has a much lower published flashpoint than the others, your pour process may need adjusting as well as the wick. CSI Neroli publishes 85°C and Gardenia 98°C, for instance, whereas most CSI oils sit in the 132–206°C band. Adding the blend below the lowest flashpoint in it is the safe rule.

Most revisions touch more than one of these at once, which is why the burn change can feel mysterious. A maker who swaps some citrus for vanilla has reduced volatile material and added heavy material in the same move. Each change on its own might have been tolerated by the wick; together they tip the balance. The only way to know which one matters is to separate them on paper first, then in wax.

It also helps to remember that your nose and your wick are judging different things. You approved the revision because of how it smells in the room. The wick responds to how the mixture flows and burns. A revision can be an improvement for one and a setback for the other, and both judgements need to be satisfied before the new version replaces the old one on your shelves.

Write the change down as a formula change log

Consider a concrete example. The old signature blend was 70% CSI Lavender and 30% CSI Bergamot Amber by weight of the fragrance portion, used at 8% of a 200 g candle, which is 16 g of fragrance. The revision keeps Bergamot Amber at 30%, drops Lavender to 50% and introduces 20% CSI Dark Vanilla to add warmth. Dark Vanilla's page lists rich vanilla and spice, caramel and cream, and dark amber and musk, with vanillin present.

Working, using 1 kg prices: Lavender 11.2 g × ₹5,221.00 ÷ 1000 = ₹58.48 and 8 g × ₹5,221.00 ÷ 1000 = ₹41.77; Bergamot Amber 4.8 g × ₹5,437.00 ÷ 1000 = ₹26.10; Dark Vanilla 3.2 g × ₹7,646.00 ÷ 1000 = ₹24.47. The old blend costs ₹58.48 + ₹26.10 = ₹84.58 per candle; the new one costs ₹41.77 + ₹26.10 + ₹24.47 = ₹92.34, an increase of ₹7.76.

Reading the change log, two things moved at once: a vanillin-bearing base component was introduced and the lightest component was reduced. The total load stayed at 8%, which rules out the third cause. Neither component has a sub-100°C flashpoint on its page, which makes the fourth unlikely. The burn change is most probably coming from the heavier fuel profile, and the test below checks that.

Walk the formula back one step at a time

Rather than re-wicking the new blend straight away, pour a short series that isolates the change. Keep wax, jar, wick, pour temperature and total load identical across every candle.

The halfway blend is 9.6 g Lavender, 4.8 g Bergamot Amber and 1.6 g Dark Vanilla. Its cost is 9.6 g × ₹5,221.00 ÷ 1000 = ₹50.12, plus ₹26.10, plus 1.6 g × ₹7,646.00 ÷ 1000 = ₹12.23, giving ₹50.12 + ₹26.10 + ₹12.23 = ₹88.45 per candle, which sits between the two versions.

Re-wick, revise, or keep both versions

If the halfway blend gives you most of the warmth and burns cleanly on the old wick, it is often the best commercial answer. You keep your approved wick across the range, the cost rises less, and the colour change is smaller.

If only the full revision delivers the character you want, and it burns cleanly one wick step thicker, adopt the thicker wick for this product and record it clearly. The old wick remains correct for any other product still using the old blend. Keep both formulas under version numbers, for example SIG-1 and SIG-2, with the approved wick, load and cure written against each.

If neither route burns cleanly, the vanillin-bearing component may simply be too much for this wax and jar at this share. Try a lower share, or a different warm component. CSI Sandalwood, for instance, publishes 0% vanillin and a 203°C flashpoint, and its woody warmth could replace some of the sweetness without adding a vanillin source.

Before the new version enters production, pour one full production-size batch and pull a test candle from the start, middle and end of the pour. A blend that burned well in six test candles should behave the same across a batch; if it does not, check mixing time and temperature before blaming the wick.

Whatever the outcome, the discipline is the same: when a formula changes, the wick approval is re-earned, and the formula card tells future you exactly which version was tested.

Where this page fits

CSI already has guides that cover parts of this question. This page answers the specific oil-in-wax question above; these go deeper on the rest:

Three things to buy for this job

Frequently asked questions