3 Warning Signs Your Tap Water is Harming Your Coffee Machine

Posted by Ofra Ronen on 1st Dec 2019

Few days ago I was helping myself to tea at a friend's house. While opening the kettle's cover to pour more water in, I've noticed the thick, stony, off white lime scale crust at the bottom of it. I've asked my friend: 'Tara, have you noticed anything wrong with the taste of your tea? 'Not really' was the answer, and then this followed: 'In a second thought, I did notice some white bits at the bottom of my mug when I finish drinking...'

You may not be as desensitised to chlorine taste in your tea as Tara is, but you may have experienced the same scale crust in your kettle, your washing machine and perhaps in your pots too. And if you happen to have a Coffee Machine and your kettle looks like Tara's, your coffee machine may be in real trouble and even on its last legs..


Because hard water contains higher than average levels of dissolved minerals. If rainwater that is naturally ‘soft’, runs through soft, spongy rocks, like limestone or chalk, it absorbs minerals from them. These minerals, often calcium or magnesium carbonate, are what make the water become hard.

When hard water is heated inside your coffee machine, the calcium salt crystals begin to separate and spread out into 

the nearby surface and forms a layer of scale. This formation slows down water flow and operation of the pipes. It can accumulate on most internal parts including the boiler and the heating element and may result in loss of pressure, drop in temperature, blockages and leakages. If scale builds up on the pipes leading to a gauge for example, it may stop reading correctly. This not only creates immediate functionality issues but also reduces the efficiency and life span of the machine.

When your coffee machine is affected, it can also affect you. Limescale formation around taps and shower heads has proven to be unhygienic and harmful for certain people. Few researches show that lime scale and chlorine, can act as irritants and make your skin feel tighter or appear irritated. Dr. Dennis Gross, a Dermatologist says that: ‘The problem with hard water is that its high mineral content prevents it from properly reacting with soap and, instead of triggering a lather, it creates a soapy layer on the skin. This not only clogs pores, but also irritates the skin, making it itchy, flaky and dry. These impurities in water make it difficult for soap and shampoo to wash off, leading to dryness of the skin, which directly irritate skin and cause redness and rosacea.’

This is also the reason for causing common detergents to be less effective, so that clothes end up looking dirty even after being washed, and that plates and glasses can look dull over time.

Limescale also leads to hair problems. According to APEC Water, ‘Washing hair in hard water causes it to become straw-like, dry and brittle. It is likely that your hair will break or start thinning because the hair follicles become blocked thereby preventing the flow of nutrients to the scalp. Your scalp may also become dry and flaky.

The good news is that it doesn't kill you, but it CAN KILL YOUR COFFEE MACHINE!

How do you know when your coffee machine has been affected?

  • Have you noticed stains on your clothes? irritant skin? dirty-like dishes? There might be a problem, check your water for hardness (this is how to do it)
  • Has coffee been tasting strange lately and water as they pour down from your machine's group head are non transparent and even flaky? Scale has already found its way to the arteries and its time for a treatment!
  • Have you noticed any loss of brewing pressure or steam pressure? What do your gauges say? Or maybe you noticed leakage from your steam wand or all of a sudden water come out of the side of your group head rather than from the middle? That is likely to be scale related.

What to do?

General rule of the thumb is to use filtered water at home to avoid the disease AND regular servicing with your certified technician who will descale your machine for you.

Note small machines with thermoblock like Breville, Delonghi and Sunbean, require often descaling which can be done at home (as per manufacturer instructions). You can get a descaler for DYI descaling here.

For Prosumer level machines, or commercially oriented, boiler machines, we recommend NOT to descale it yourself but to use filtered water, clean the machine regularly and check in for general service every 18 months, where your machine will be tested for scale and be treated accordingly.

If you suspect scale build up, do the following:

  • Check your water hardness level with the Water Hardness Strips, it's good to know how harmful it is also for your other appliances and for your skin
  • With a Thermoblock machine, buy a descaler and descale it at home right away and on average every 6 months after that
  • With a boiler machine, check for the nearest certified technician and bring it down for service. If you are in Sydney, you'll find all the info on our Service Centre here. If you are in a remote area with no access to a technician, ring Di Bartoli technical support for an advice. We will troubleshoot your machine and offer best course of treatment
  • For all machines in general, we recommend to purchase the right water softening solution for your machine

We've sourced a range of products and services to provide the right solution for your lime scale build up. Scale is responsible for up to 70% of all breakdowns causes in our workshop, and in certain cases, particularly with machines that employ aluminium boilers, that may end in a 'write off' when the technician's recommends not to proceed with the repair for being time consuming and costly.

While keeping your machine scale free at home can be fairly easy and affordable task, it is surprising how minimal awareness and action is taken by coffee machines owners to do the right thing by their machine, protect their investment and enable the life expectancy it was designed to have. Once we become aware of the need, It will be good to shift our minds and see water filtration and / or regular descaling as asset protection investment and a cost saving exercise, as it will save you from lugging often the machine to the workshop and incurring high repair bills that can easily be prevented.

Remember to stay away from assumptions. Just because your neighbour's machine didn't suffer from scale, it doesn't mean that the water going through the pipes that lead to your unit, pass through the same terrain. In Australia, it is fairly accurate to say that water in capital cities are softer than the country side and that NSW & VIC water are generally softer than in WA, QLD, NT, SA & TAS, but it's always recommended to test your own water, as the most accurate hardness level measure. Even in Sydney we see a machine coming over with scale related issues, while another machine (same model) from the same street will have little scale if any. Adding on heating and cooling frequency as a contributor to scale rate, it will make sense to get definite answers.

To learn more about water quality and how it affects your coffee machine, and to find out the right water filtration solution for your machine, click here.

Please contact our friendly technical support team with any question relating to your water quality.

© 2020 Ofra Ronen