The thing about limescale formation is they can spread throughout the water network. Meaning if we spot limescale at somewhere, it means that somewhere else might also be plagued with it. This can cause a series of issues, and of course a lot of repairs. Even if the machine is armed with the most heavy duty components, the components can only be effective if they are not hindered by blockage.
Restoration process like descaling is time-consuming and can cause irreversible damages to the components and erode the metal in the process. If you are not aware, descaling voids the warranty for most high end machines. The other problem is, running the system with descaling liquid might not clear off everything as some valves have inner compartments that are hard to reach. Limescale can also form on top of the boiler where the descaling agent can’t reach, the top of the boiler is where most of the components and sensors are located.
As such, the best thing to do is to avoid the situation and keep your water soft. Limescale free machines are capable of running for decades with minimal repairs. It is much easier and economical to prevent limescale from building than finding ways to get rid of them.
Here are some photos of limescale formation on espresso machines used in Singapore.
That is not all. Limescale can cover the sensors, the heating elements, and cause the machine to malfunction. Imagine this, the pressure sensor is coated with limescale and can’t work, the heating element keeps heating, and burn itself out. Problem with one component can result in problems in other components.
HOW TO SOFTEN?
There are many solutions available on the market.
Water softening cartridge (Recommended)
This is the most common solution recommended by manufacturers for semi-professional espresso machines and is only effective for home or office environment with smaller usage using the internal water tank. If you are thinking of connecting your machine to the tap, this thing won’t work.
Base on the water condition in Singapore, which has a hardness of about 7 French Degrees, the cartridge works for approximately 40 litres before they must be replaced. If you are using mineral water or if you are using in other countries, then the hardness might be much greater and you will have to replace the softener much earlier.
Before using, rinse the water softener with clean water for 10 minutes.You must not allow the softener to dry up. If the resins inside are dried up, it will no longer be effective in softening.
For Bezzera machines with a water tank of 4 litres, this includes but not limited to Magica, Mitica, Strega, BZ16, Galatea Domus, etc. The water tank will require a little modification to accept the water softener cartridge.
For machines that draw water from a silicon inlet hose like the Bezzera BZ07, BZ09, BZ10, BZ13, Expobar Pulser, Brewtus with Vibration pump, Leva EB61, etc.
This little cartridge can be attached to the inlet hose directly, you don’t need to do any modification but you should remove the dirt filter before attaching the softener.
Also do not assume that all water filtration systems can remove limescale. Most water filtration systems sold in Singapore are designed to remove toxin, microbes, metal and debris, but does almost nothing for softening.
Lastly, some water filtration systems are very aggressive and may totally strip off all the minerals in the water. The water produced in this way, is very similar to distilled water. The problem with distilled water is they are a little erosive, gradually stripping metal it gets contact with. This will thin the metal and the eroded metal goes into the water, then into your drink. Such erosive water should never be used. To counter this, some machines detect water in the water tank by electrolysis, sending a signal in the water and detecting at the other end of the water tank. For distilled water, the signal cannot be passed and the machine won’t operate, as it assumes that there’s no water in the water tank.
If you intend to purchase a commercial filtration system, it is best to speak to the vendor and ask them specifically if their product can soften
1. Water pitchers with filters
We are aware that certain brands of water pitchers with built-in filters can reduce the hardness of the water. The filter cartridge in the water pitcher has to be replaced regularly.
As we don’t carry such products, users will have to check with the vendor or manufacturer to double check its efficacy in softening the water.
However, if the water filters has activated carbon in it. The filter might release carbon dust, which might get into the boiler and cause adverse effects.
2.Water filtration systems
If you are planning to plumb your machine to the tap, then you will need to look at this.
Water filtration systems are larger canisters of filters placed along the water network to clean the water before they exit out from the tap.
Again, users will have to check with the vendor or manufacturer if their models work in softening the water. Most filters in Singapore are not made for softening.
If the filter has activated carbon, it might release carbon dust which might end up in the boiler.
Also some systems might purify the water so much until it has absolutely zero minerals in the water, almost like distilled water. This can be an issue as distilled water has an erosive effect on the yellow metal, and the water probes in the machine might not be able to detect the water in the boiler.
It is actually possible to use distilled water, but the water must be remineralised by adding some minerals back. Remineralisation keeps the water from being too erosive. Else metal can get eroded and stays in the water.
Water level in the boiler is detected by conduction via the water probes. Using distilled water will make such detection difficult or impossible, which can cause massive damages. If the process of remineralisation is properly done, it will form a layer of copper oxide on the yellow metal that protects it from further corrosion. Using this method will not cause limescale to form. Users who are particularly interested in exploring their coffee can use this method to control the taste by controlling the hardness.
To add the beneficial minerals back into the water.
We will suggest using the following formula:
1. Add 4.2 grams of sodium bicarbonate(baking soda) and dissolve it in 100 mL of distilled water to form a solution.
2. Add 2 mL of this bicarbonate solution to each litre of distilled water. This will give you 84 mg/litre.
Many manufacturers will recommend descaling which is running through the system with a food-grade acid to dissolve the limescale. This is almost equivalent to having chemotherapy for a cancer patient and it’s common to see users who had issues after performing the task.
Sometimes, it can cause clogging issues if the limescale is unable to fully dissolve and flake off from the walls. The solid residues will travel within the water network and might end up in a valve. This might cause sealing issues among the gaskets which render the valves ineffective.
On the other hand, if descaling is done too intensely, it might erode the brass fittings and harmful metal gets released into the water. It doesn’t matter if your machine is using a stainless steel boiler as the fittings and grouphead are usually made of brass. Consciences brands like Bezzera began using food-grade brass that has almost no lead, on top of it, they plate a protective layer over it. They also don’t use brass boilers which have close contact with the water inside. All these protections can still degenerate during the descaling process.
We had also seen cases where users destroy their pump and heating element while descaling. The descaling process can overstress the pump as it has to work longer to pump a large amount of water, several times. If the machine is using a vibration pump, then descaling must be done with extra caution. Vibration pumps have a duty cycle of 2:1. For every 2 minutes of work, it has to rest for a minute. The long and exhaustive process of descaling, can easily kill the pump if the user did not take heed and allow sufficient rest time.
Another problem with descaling is the descale solution cannot travel to every part of the machine. It cannot reach the top portion of the boiler where we normally see limescale forming and where many of the components are located. That includes the water probes that sense water, relieve valve that bleeds out excess air, the safety valve that keeps the machine from exploding, and the pressurestat which controls the pressure and heat in the boiler. We had seen some users who had done a method recommended online which involves disconnecting the water probe and allow the pump to flood the boiler full. This method can be quite dangerous if it’s done incorrectly. If the user forgot to open the valves to release excess pressure, water will enter into the gauges and blow them up. We had also seen users who had used descalers that are too strong and destroyed the heating element.
Another method some users do is they dismantle every fitting, tube and the boiler, and submerge everything into a pail of descaling liquid. This allows the technician to visually inspect if limescale is fully dissolved with no remaining residues in the boiler. The problem with this method is it’s very tedious, costly and at the same time, the process erodes both sides of the metal, inside and outside. This can thin down the walls of the metal, causing erosion and eventually holes to form, such condition is considered beyond repair.
WHAT’S THE BEST SOLUTION?
Users should commit to preventive measures like water softening to keep the damage minimal. As we had mentioned above, it’s more economical and easier to soften the water than to think of how to get rid of the limescale.
After 5-10 years, we will suggest sending the machine to us to check some of the key components if they are plagued with limescale. If the amount of limescale is very light, then good job, you shouldn’t need to do or worry much. A properly maintained machine will definitely last for decades with only a few parts replacement.
If limescale is spotted, then it’s better to perform a light descaling as well as replacing some key components. You will never recover metal that gets eroded, which can cause the toxic in metal to start leach.
For the same reason, that’s why it’s better to drink a coffee from your own machine than to drink from a cafe that descales their machine every quarter!