It is important to use only soft water to run on any types of coffee machines. Most scale is calcium carbonate CaSO₄. CaCO₃ or MgCO will also make up a part of it, water softening is the most important step to follow in using any types of coffee makers.
Scale formation can cause serious problems to the machines, normally resulting in expensive repairs. It is often the main culprit to machine failure.
Restoration process like descaling is time-consuming and can cause damages to the components and metal in the process.
As such, keeping the water condition soft is the most important step to extend the longevity of an espresso machine, it is much better to prevent limescale from building than performing too much descaling.
Here are some photos of limescale formation on espresso machines used in Singapore.
That is not all. Scales can cover the sensors, the heating elements, and cause the machine to malfunction. As scales are solids, the restoration process will be time-consuming as time is needed to dissolve the minerals and rinse them out of the machine. Many tests are also required after the restoration.
HOW TO SOFTEN?
There are many solutions available on the market.
On the other hand, not all water filtration systems are effective in reducing limescale. Some will do well in removing microbes, toxic and metal but does nothing to limescale. Also, certain water filtration systems may remove all the minerals totally, this will be a problem because the water may not be detected by machines using electrolysis to conduct a signal on its water condition. In addition to that, water which is aggressively filtered to have zero mineral, similar to distilled water, will have an erosive effect on the yellow metal within the machine. Which can thin the metal layers, and leach into the water.
Please consult a water filtration specialist to advise for more appropriate solutions.
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.
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 some other countries, then the hardness might be much greater and you will have to replace the softener much earlier.
Before using, rinse water softener with clean water for 10 minutes. It’s important the water softener remains in the water and does not dry out. If resins dry out, it will no longer be effective in softening the water.
For Bezzera machines with a water tank of 4 litres, this includes but not limited to Magica, Mitica, Strega, BZ16, Galatea Domus. The water tank will require a little modification to accept a water cartridge.
For machines that have a silicon suction hose like the Bezzera BZ07, BZ09, BZ10, BZ13, Expobar Pulser, Brewtus with Vibration pump, Leva EB61.
This little cartridge can be attached to the inlet hose directly. Please remove the dirt filter before attaching the softener.
BILT Oscar 150 Water Softener
This is a bag of resins which you can place inside the water tank. It will cure the water but it will take some time to be effective.
Effectiveness guide and softening time.
|Germen Degrees||PPM mg/L CaCO3||Min Softening time (Hours)||Max Treated Litres||Drinks (100cc)|
Singapore’s PUB Water Quality Rating
Average : 66 mg/L
Range across Singapore : 26 – 203 mg/L
Expiry: 12 months from purchase date or upon finishing the maximum treated litres above.
The “Min Softening time” is the time it starts to reduce hardness, it’s recommended to have the softening prolonged for 2 to 4 times longer.
Users may want to soften water in advance, done by treating the water to be used in another water vessel before pouring into the espresso machine.
They are not suitable for all Expobar or any machines with water tanks that do not have openings wide enough to insert the Oscar water softeners
1. Water pitchers with filters
We note that certain brands of water pitchers with built-in filters work in reducing 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 if their models do have the capability to soften the water.
Do note that some water filters with activated carbon produce carbon dust, which might get into the boiler and cause adverse effects.
2.Water filtration systems
Some users will prefer to use a filtration system.
If you are plumping in or you are expecting heavy usage, this will be the most recommended.
Again, users will have to check with the vendor or manufacturer if their models work in softening the water.
If the filter has activated carbon, it might produce carbon dust which can transfer to the boiler.
Also some systems might purify the water too much and 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 it might not ignite the water detection system going by conduction via electrolysis.
It is possible to use distilled water, but the water must be remineralised by adding some minerals back. Remineralisation keeps the water from being too erosive, which reduces metal leaching into the water. If the process is properly done, it can form a layer of copper oxide on the yellow metal that protects it from further corrosion. 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 first adding 4.2 grams of sodium bicarbonate(baking soda) and dissolve it in 100 mL of distilled water to form a solution.
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. We will normally reference this to having a chemotherapy for a cancer patient and it’s common to see users who had issues after performing the task.
Clogging issues can surface if the limescale is not properly dissolved and flaked off from the walls. The solid residues will travel within the water network and 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 starts to get released into the water. It doesn’t matter if your machine is using a stainless steel boiler as the fittings and grouphead is usually made of brass. Consciences brands like Bezzera usually uses food grade metal which has a protection layer over it, but they can degenerate during the descaling process. We had also seen cases where users destroy their pump and heating element during the process. After all, we have to remind that 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 such pump if the user did not take heed and allow sufficient rest time.
Another problem with descaling is the descaling solution only travels to where the water network can bring it to. The problem with this is it cannot descale the top portion of the boiler, which is the place we normally see limescale forming and where many of the key components are. Particularly the low water probes, vacuum relief valve which removes excess air from the boiler, 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 involved disconnecting the water probe and allow the pump to flood the boiler full. This method is quite dangerous when done incorrectly if the user forgot to remove open the tapes to release excess pressure. We had seen many users who had blowed up their pressure gauge with this method.
Another method some users do is they dismantle every tube and boiler, and submerge into a pail of descale. This allows the user to visually check if limescale are all dissolved with no remaining residues in the boiler. The problem with this method is it’s very tedious, costly charged by technicians and at the same time the process erodes both sides of the surface of the metal, inside and outside. This can decrease the structural integrity as well as thinning the walls of the metal, causing erosion and eventually holes to form, resulting in beyond repair conditions
WHAT’S THE BEST SOLUTION?
The best solution is to of course soften the water as much as possible. After a 5-10 years, we will suggest checking for limescale. If the amount of limescale is very light, then good job, you shouldn’t need to do or worry much.
If limescale is spotted, then it’s inevitable that a light descaling as well as replacing some key components might be necessary. You will never recover metal that gets eroded or reverse the process that metal starts to release into the water though, so we will usually recommend replacing certain brass tubes as well.