With a large percentage of UK inhabitants living in a ‘hard water’ area, many of us struggle with limescale that causes stained clothes, fogged up glassware, blocked heating pipes and soap scum. Limescale is a buildup of minerals that are found in hard water, namely calcium and magnesium. But luckily, there are some ways you can soften hard water, which can make your appliances more efficient and last longer.

Does hard water affect your boiler?

Hard water can have a negative impact on many of your home appliances, but particularly your boiler and the rest of your heating system. As the boiler heats up the water that will be pumped around your radiators and provided to your taps, the minerals in the water clump together to form larger chunks known as limescale. These deposits can stick to the surface of pipes, radiators, taps and other aspects of the heating system, including parts within the boiler itself.

As these deposits build up, the diameter of the pipe gets smaller and smaller meaning less water can flow through it, as shown in the image below. When this happens, you may find that radiators struggle to get hot or that they have cold spots. 

While this may not seem like a big issue, the limescale can begin to act as an insulator. This is when it can really affect your boiler. When this problem occurs, your boiler needs to work even harder to heat your home to the set temperature. But, as limescale buildup only increases when water is heated, a kind of never-ending cycle is created. As the temperature of your boiler increases so does the risk of scaling Eventually, the metal components of a boiler will likely overheat and could even fail completely.


This means that not only does limescale affect your boiler, but your heating bills too. You’ll likely be using more energy to complete everyday tasks, such as heating your home, boiling the kettle and running the dishwasher. 

How do you make hard water soft?

Option 1: Water Softener

A water softener is a device that connects to your heating system, usually where access is easy, such as under your kitchen sink. This device is around the same size as a pull-out kitchen bin and works by removing the calcium and magnesium ions that make water hard.

First, water from the mains supply enters the system and moves through resin beads that are located in the cylinder. These beads allow a process known as ion exchange to occur. This is when the unwanted minerals are removed and instead replaced with salt. Then, the excess minerals are flushed from the system completely, leaving you with softened water.

This isn’t a process that can be done just once. Your home is always pulling in fresh water from the mains and so a water softener is a device that should be fitted permanently. The salts will occasionally need replacing so that the softener can continue to do its job

Option 2: Ion exchange filter

While the above method can be used to soften the water that enters your home’s heating system, you may wish to soften your tap water too. In order to do this, you can attach an ion exchange filter to your taps. This filter works in much the same way as a water softener, using resin beads to complete the ion exchange process.

Unlike a water softener, which needs to be filled with salt regularly to keep the process working, a tap softener just needs its filter replaced every now and then. The device means that any water that comes out of the tap, either for cooking with, boiling with or drinking, will come out soft. You can wave goodbye to descaling your kettle!

Most devices have a switch so you can turn the filter off, meaning you can still get hard water if you prefer it - many people actually say they prefer the taste of hard water. You can buy similar devices for your shower too, as it’s thought that soft water is better for your hair and skin.

Option 3: Use chemical softeners


Softeners can be added directly to your appliances too. Dishwasher salts need to be added to your dishwasher regularly to keep limescale at bay and prevent your nice glassware from fogging up. It could keep the appliance running for longer and make it more efficient, too.

Similarly, chemical softeners can be added to your washing machine to prevent the hard water from staining your clothes and clogging up the pipework, reducing the appliance’s efficiency. Non-precipitating softeners, like popular brand Calgon, bind the calcium and magnesium minerals together so they can’t react with the water or your laundry detergent. These can be added directly to the machine each time you use it.

It’s worth noting that you can use all three of the above methods together to combat issues with hard water in your home rather than using just one. A water softener can prevent limescale from damaging  your heating system, whereas the other two methods can assist your other appliances too.

Sources:

mrcentralheating.co.uk/blog/hard-water-affect-central-heating-system-boiler/
harveywatersofteners.co.uk/consumers-guide-water-softening/
aquacure.co.uk/knowledge-base/how-water-filters-work
calgon.co.uk/calgon-3in1/
dynapipe.co.uk/how-to-prevent-limescale.htm
halcyanwater.com/limescale-on-heating-system/ 

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