SoluCalc cylinder replacement: 3 simple ways to replace your CO₂ cylinder

The pressure gauge has dropped to 0, the LED indicator is flashing, or your SoluCalc Connect app has just notified you: your CO₂ cylinder is empty. No need to panic, replacing your SoluCalc cylinder is one of the simplest tasks in the entire anti-limescale system.

You have three options, depending on your time, your budget and how much you want to handle yourself. In this guide, we'll walk you through which option is best for you and how each scenario unfolds, step by step.

How do you know your CO₂ cylinder is empty?

Before thinking about replacement, you first need to recognise the right moment. Three signals will alert you:

• The left-hand gauge on the pressure regulator drops to 0. Unlike a car's fuel gauge, this gauge stays on a stable value as long as there is gas in the cylinder, then suddenly drops to 0 the moment it becomes empty.
• The empty-cylinder LED detector lights up (optional, but strongly recommended to avoid being caught off guard).
• The SoluCalc Connect app sends you a notification as soon as the estimated level reaches zero — handy for planning the replacement in advance.

If you don't have any of these tools, the most obvious sign is unfortunately the return of visible limescale on your taps, in the shower or on your kettle's heating element. At that point, it's time to act quickly to prevent limescale from building up in your pipes again.

The 3 ways to replace your SoluCalc CO₂ cylinder

Good news: SoluCalc has designed several solutions to suit every type of user. Here are the three options.

Option A — The Service Confort Gaz at home (the most convenient)

Would you rather have everything taken care of for you? Then this is the option for you. A certified SoluCalc technician comes to your home, swaps your empty cylinder for a full one, and carries out a full readjustment of your appliance — free of charge at every visit.

Here's how it works in practice:

• You book an appointment via the SoluCalc contact form or through your approved installer.
• The technician arrives at the agreed time with a full cylinder. You don't have to transport anything.
• The cylinder swap itself takes less than 10 minutes.
• The technician then checks the pressure, the CO₂ flow rate setting and the tightness of the injection module.
• They finish with a performance check to confirm everything is running perfectly before leaving.

The whole visit takes less than an hour, with no mess and no work done in your home. This is typically the solution chosen by households who want a completely hassle-free service and the certainty that their appliance is correctly adjusted every year.

👉 For more details on this option, visit our Service Confort Gaz page.

Option B — On-site exchange in Fleurus (the fastest)

Do you live near Fleurus, have a car with enough boot space, and prefer to handle the swap yourself? Then exchanging on site is the fastest and most cost-effective option.

Address: Rue du Rabiseau 15, 6220 Fleurus, Belgium Access: via the right-hand shutter of the building Opening hours: 7:30 AM – 12:30 PM and 1:00 PM – 4:00 PM, Monday to Friday (by appointment)

The process is even simpler:

• You load your empty cylinder into your car (10 kg, roughly the size of a barbecue gas bottle).
• You arrive in Fleurus during opening hours.
• You leave straight away with a full cylinder, ready to be connected.

Once you're back home, connecting the new cylinder takes just a few minutes. We explain exactly how in the next section. For more information on the extended opening hours, see our dedicated article on the Service Comfort Gaz and the new opening hours from 7:30 AM.

Option C — Replacement via a third-party gas supplier (the most flexible)

Do you live far from Fleurus, or do you already have a food-grade gas supplier nearby (a brewery or industrial supplier)? You can perfectly well source a 10 kg food-grade CO₂ cylinder from:

• Air Liquide
• Westfalen
• A local brewery (the CO₂ used in beer pumps is exactly the same as the one used by SoluCalc)

Once you have the cylinder, connecting it is your responsibility. The procedure itself is straightforward, but it requires a minimum of care:

• Shut off the main water supply to your home.
• Unscrew the pressure regulator from the empty cylinder (using the right spanner).
• Screw the pressure regulator onto the new cylinder, checking the seal.
• Open the cylinder valve gradually and run a leak test using soapy water on the connection.
• Make sure the gauge shows normal pressure, then turn the main water supply back on.

⚠️ Worth knowing before you choose this option:

• The cylinder usually comes with a deposit of around €100 (refunded when you return the cylinder).
• If your SoluCalc needs a new flow rate adjustment (for instance, if your consumption or your water hardness has changed), you'll need to do this yourself or call out a separate technician.
• If you're not particularly handy, the risk of an undetected leak or a poorly tuned setting argues in favour of options A or B.

Quick comparison of the 3 options

How much does a cylinder replacement cost?

The cost of a cylinder replacement remains one of SoluCalc's biggest advantages over a traditional salt-based water softener.

• Refilling a 10 kg food-grade CO₂ cylinder typically costs between €20 and €55 per year, depending on the supplier and the chosen formula.
• The cylinder deposit is approximately €100 (refunded when you return the cylinder).
• The Service Confort Gaz at home includes the swap and the free readjustment. Request a personalised quote via our contact form.

To put this into perspective: a household of 4 people uses about one cylinder per year, which works out to €5 per person per year for full anti-limescale protection. Compare this to the dozens of kilos of salt you'd have to buy, transport and store every year with a traditional softener.

How often should you replace the cylinder?

The rule of thumb: roughly one 10 kg cylinder per year for a household of 4 people living in a region with medium to high water hardness. More specifically:

• 1 to 2 people → 18 to 24 months
• 3 to 4 people → 10 to 12 months
• 5 people or more → 8 to 10 months
• Very hard water (> 35 °f) or intensive use → 20 to 30% shorter

Not sure how hard the water is in your area? Use the SoluCalc water hardness calculator directly on the homepage, or read our article Why are some regions in Belgium more affected by hard water than others?.

FAQ — Your questions about replacing the SoluCalc cylinder

What happens if I delay replacing my empty cylinder? Water keeps flowing as normal, and you face no immediate risk of damage. However, without CO₂ injection, limescale will gradually start building up again on your taps, heating elements and pipes. The longer you wait, the longer it takes to get everything back in order.

Can I safely replace the cylinder myself? Yes, the operation is technically accessible. The CO₂ used is food-grade — the same as in beer pumps or SodaStream machines — and it is not explosive. Just make sure you carry out the replacement in a well-ventilated room, check the connections with a leak test, and never force a stuck pressure regulator.

How long does a 10 kg cylinder last? For a typical household of 4 people, count on 10 to 12 months. This duration varies depending on your water hardness, your consumption and how your appliance is configured.

Is the cylinder deposit refundable? Yes. The deposit (around €100) is returned to you when you hand the empty cylinder back to your supplier or exchange point.

Is my SoluCalc automatically checked when the cylinder is replaced? Only with the Service Confort Gaz at home (Option A), where the readjustment is included and free of charge. For options B and C, it's up to you to check it yourself or schedule a separate technical visit if needed.

Is there a risk of leaks or any safety concern during the replacement? CO₂ is heavier than air, so it tends to accumulate at floor level if a major leak occurs. This poses no problem in a normally ventilated room. For installations in a windowless cellar or an enclosed space, follow your installer's recommendations or simply opt for the Service Confort Gaz.

Can I just have a cylinder delivered to my home, without a technician visit? Yes, get in touch via our dedicated form and we'll discuss what's available in your area.

Which option should you choose? Our recommendation

• You want maximum convenience and an appliance that's always perfectly adjusted → Service Confort Gaz at home (Option A).
• You live in Wallonia, near Fleurus, and you like getting things done quickly → On-site exchange (Option B).
• You're handy, you have a food-grade CO₂ supplier nearby and you handle the maintenance yourself → Third-party supplier (Option C).

Whichever option you choose, the bottom line is this: with SoluCalc, a single action per year is all it takes to keep your water perfectly protected against limescale. No salt, no waste water and no complicated maintenance. That's exactly what makes the difference compared to traditional solutions.

Ready to have your cylinder replaced the easy way?

The Service Confort Gaz is designed to take the hassle out of maintenance: a qualified technician, a quick swap, a free readjustment. Book your appointment today.

👉 Request a cylinder replacement via the Service Confort Gaz