How Many Candles Can a 100L Wax Melting Tank Actually Support Per Day?

Most buyers sizing a melting tank ask the wrong question first. They ask what volume they need, and get an answer in litres — which tells them nothing about whether they can ship 2,000 candles on Friday.

The useful question is: how many kilos of wax can this tank turn into saleable candles in one working day? That number is arithmetic, not opinion. Below is the arithmetic, with every assumption stated so you can recompute it for your own candle weight and shift pattern.

A 100-litre stand-type melter. The volume on the nameplate is not the number of kilos you can pour.

Step 1: convert litres into kilos of wax

A 100-litre tank does not hold 100 kilos of wax. Wax is lighter than water, and you should never fill a melting tank to the brim — melted wax expands, and a tank filled to the top will spill the moment it heats.

Two working assumptions:

Wax density: about 0.9 kg per litre. This is a reasonable planning figure for soy and paraffin blends. Your supplier's datasheet is the authority for your specific wax; coconut and some soft blends sit slightly lower, beeswax slightly higher.

Practical fill level: about 80%. This leaves headroom for expansion and for the mixer.

So a 100-litre tank gives you roughly 90 kg nominal, about 72 kg practical per batch. That is the number everything else is built on.

If your wax is denser or lighter than 0.9, scale linearly: a 100-litre tank at 0.85 kg/L practical-fill gives you 68 kg per batch instead of 72.

Step 2: convert kilos into candles

Divide the batch by the wax weight per candle. Note that this is the wax weight, not the gross weight of the finished candle — the jar, lid and wick add to shipping weight but come out of a different budget.

Chart 1 — the same table as a chart, for the quick comparison.

That table is the answer to the headline question, in one batch. What turns it into a daily figure is how many batches you can run.

Step 3: work out how many batches fit in a day

A melting tank runs a cycle, not a continuous stream. One cycle is: melt time + fill time + drain and reload.

The published melt time for a 100-litre stand-type electric melter is 1 to 2 hours to reach working temperature. Add 20 to 30 minutes for draining, refilling with solid wax, and a basic wipe-down between colours. That gives a cycle of roughly 2 hours at the top of the melt range, and around 1.7 hours at the bottom.

Over a 7-hour productive shift — which is what remains of an 8-hour day after breaks and setup — that is three batches, not four. Four batches would need eight hours of melting alone, before a single candle is poured. Plan on three and treat a fourth as a bonus when the wax is soft and the operator is ahead.

Step 4: put it together

Daily output = (usable wax per batch ÷ wax per candle) × batches per day

Chart 2 — single shift versus double shift.

If you are producing 200 g jar candles on one shift, a 100-litre tank supports around 1,080 candles a day. On two shifts, double it.

Treat these as planning figures, not promises. They assume the tank is the only constraint, the operator is not waiting on anything, and your containers are staged and ready.

Where the bottleneck actually sits

Filling 360 candles on a double-nozzle machine takes 6 to 12 minutes. Melting the wax to do it takes 90 to 120 minutes. For jar candles in the 200 g to 400 g range, melting dominates by a factor of ten, and that ratio is the single most useful thing to understand about sizing a melting tank.

But the ratio is not fixed — it moves with candle size, and this is where most sizing advice goes wrong. A 50 g votive batch is 1,440 pieces. On a single-nozzle machine at 10 to 30 pieces per minute, filling those takes 48 to 144 minutes, against 90 to 120 minutes of melting. At the slow end, filling is no longer a rounding error; it is the bottleneck, or close to it.

So the honest version is this: on a 100-litre tank, melting is the constraint for jar candles, and filling becomes the constraint for small votives on a single-nozzle filler. Check which side of that line your product sits on before you buy anything.

Two consequences follow for jar production:

• Buying a faster filling machine while keeping one melting tank adds capacity you cannot feed.
• Sizing the tank up by one step usually buys more output than any change on the filling side.

Three ways to raise output without buying a bigger tank

Add a holding tank. Keep a second, smaller tank at working temperature so the filling machine draws from it while the main tank melts the next batch. The melt wait comes off the critical path, and the same filling machine can run most of the shift instead of a fraction of it.

Run two melts per shift in parallel. Two 100-litre tanks cycling at offset times give you roughly the throughput of a 200-litre unit, with one advantage: if one goes down for maintenance, you still produce.

Change the product mix, not the machine. A 100 g candle uses half the wax of a 200 g candle, so one batch yields twice the pieces — but each piece still needs its own fill cycle, so total filling time per batch goes up, not down. The gain from smaller candles is units per kilo, not minutes per kilo. If your order book allows the mix, that is still a good trade; just do not expect the filling side to get faster.

When 100 litres is the wrong size

A 100-litre unit is a workhorse for medium batch production: it suits factories running several product lines in modest volumes, and it suits larger factories as a secondary or sampling tank.

It is the wrong choice in two situations.

If you are sampling or running a home studio. A 30-litre or 50-litre trolley unit heats faster, moves where you need it, and costs less to run empty. Melting 72 kg to pour 20 test candles wastes both time and wax.

If melting is already your constraint at 100 litres. Two or three tanks, or one 200 to 500-litre unit, is the honest answer. The 500-litre and 1,000-litre induction units exist for a reason: at some volume, batch size stops being a convenience and becomes the production plan.

What the tank does not do

Three things to get straight before ordering, because they are the most common misunderstandings.

It melts and holds. It does not fill. You need a separate filling machine — single nozzle, double nozzle, or a multi-head unit — plumbed to the tank outlet. The tank and the filler are sized together, not separately.

It does not feed itself. Solid wax goes in at the top. On a stand-type unit with ladder and handrail, loading 25 kg slabs is a two-person job done safely; on a low trolley unit it is easier but the batch is smaller.

It does not fix temperature drift on its own. A double-layer water or oil jacket keeps the wax at temperature without scorching it, and that matters for scent retention and colour stability. A 0 to 120 °C working range covers soy, paraffin, beeswax and coconut blends, but the accuracy of the hold depends on the control, not just the tank.

Two controllers, two zones — the hold accuracy lives here, not in the tank volume.

The size, in one line

The YD-LS-100L is a stand-type, 100-litre, double-layer jacketed electric melter with ladder and handrail, 220 V supply, 0 to 120 °C working temperature, 1 to 2 hour melt time, 1000 × 920 × 1640 mm, 130 kg. An optional mixer evens out colour and fragrance before filling.

Whether it is right for you depends on three numbers you already have: your candle wax weight, your target daily output, and how many hours a day the line actually runs.

FAQ

How accurate is this calculation? The formula is exact; the inputs are estimates. Wax density and fill level are the two variables most likely to differ. Recompute with your supplier's density figure and your real fill practice before committing to a machine size.

Can I melt overnight and fill in the morning? Yes, and many factories do. A jacketed tank holds temperature well. The limitation is that a single tank holds one colour and one fragrance at a time, so overnight melting suits a single-SKU run, not a multi-scent day.

Does a bigger tank melt faster? No. Larger tanks generally take longer to reach temperature because there is more mass to heat. What a bigger tank gives you is more kilos per batch, not a shorter cycle.

What if I produce several scents a day? You need either multiple tanks, or a tank plus a cleaning routine between scents. Changing fragrance in a single tank costs changeover time, and residue in the outlet valve is the usual cause of cross-contamination.

How much labour does a 100-litre tank need? One operator can run the melt and fill cycle; loading solid wax is easier with two people on a stand-type unit. The real labour question is usually not the tank but the packing end of the line.

Send us your candle wax weight, container size and target daily output, and we will run the same arithmetic on your numbers. Talk to our engineers — including when the honest answer is that you do not need a bigger tank.