Water Softener

Buyers Guide

Rainfall is formed of naturally soft water. However, due to our climate and the geological composition of our landscape, hard water is widespread across the UK. This can lead to problems such as ineffectual cleaning and the build-up of limescale, which can cause damage to plumbing and water heating systems as well as looking unsightly. At Harvey™ Water Softeners, we have over 40 years of experience in building the very best water softening technology. We have created this comprehensive water softener buying guide to provide you with more information about hard and softened water.

Things to know before buying a water softener

The following are some key things you should know before buying a water softener, and will be covered for you in this guide. If you do have any more questions, you can get in touch with our team or book a free, no obligation demo where a qualified technician will visit your home and talk you through how the softener will work for you.

  • What is a water softener?
  • What is hard water?
  • Is my water hard or soft?
  • How does a water softener work?
  • The benefits of a water softener
  • Types of water softeners
  • Water softener installation
  • How much does a Harvey™ Water Softener cost?
  • Other FAQs

What is a water softener?

A water softener is a device which connects to your plumbing system at an easy access point, like underneath a kitchen sink. It removes the calcium and magnesium minerals found in hard water to convert it into soft water. Using a water softener allows you to avoid many of the problems caused by using hard water.

Water softeners work using a process called ion exchange, in which calcium and magnesium ions from hard water are exchanged with sodium chloride (salt) via a special resin. The water goes into a pressure vessel where it moves through the resin beads, and the calcium and magnesium are replaced by sodium. These calcium and magnesium ions are then removed in regeneration cycles, leaving behind only soft water.

Learn more about how a water softener works

Blockimage Buyersguide

The perfect water softener for your home will depend on many different factors. Here are some of the things you’ll want to take into account:

How often does my water usage change?
For example, do you have family that come to stay, or do you often go away at weekends?

How much water do I use?
Do you have a large family, or do you often find that everyone in the household needs to use water at the same time of day?

What sort of plumbing do I have?
A system with large pipes will need a water softener that can process water more quickly. A system with tanks in the loft will have a more constant pressure, whereas a system with a mains water supply that enters through the garage will need a different installation plan.

Book a free demo to find out more.

What is hard water?

Hard water is water which contains a high volume of mineral ions due to how the water has travelled through the Earth. Hard water contains magnesium and calcium minerals, which makes it hard to form a soap lather. This can often make water seem cloudy and is responsible for causing limescale to form. Soft water, on the other hand, contains little or no dissolved calcium or magnesium and forms a soap lather much more easily. As no salts are present, soft water does not contribute to the formation of limescale. This is the main difference between hard water and soft water.

What are the effects of hard water?

The negative effects of hard water come in the deposition of scale and scum. You may be familiar with the telltale signs. Tidemarks around baths and basins, unsightly white marks on sinks, toilet bowls, and shower heads. In worst case scenarios, the build-up of this material can create blockages in pipework and lead to the premature failure of water heaters.

Due to its composition, hard water can result in a less than effective wash. Its rich mineral makeup prohibits an effective reaction with soap. This basically means that it is harder to create lather, foam, and bubbles, resulting in a less than effective clean. Clothes can be left grey and dingy, whilst dishes and glasses can appear dull and smeared. It can really affect the longevity of your clothes and kitchen appliances.

Learn more about hard water





Hard water is widespread across the entire UK, though some places have a richer composition than others.

To give you a better sense of the distribution of water composition in the UK, this map provides a more accurate overview.

As you can see, Wales and both North West and South West regions have the softest water, whilst most of the UK is host to hard water. It should also be noted that Northern Ireland and Scotland are naturally soft. You can also use our handy postcode tool to find out the exact hardness of the water in your area.

Check out water hardness calculator

How is water hardness measured?

There are many ways in which water hardness is measured. In the following table, we have displayed how water hardness is measured further afield.

water hardness measured

How does a water softener work?

Water softeners work using a process called ion exchange, in which calcium and magnesium ions from hard water are exchanged with sodium chloride (salt) via a special resin. The water goes into a pressure vessel where it moves through the resin beads, and the calcium and magnesium are replaced by sodium. These calcium and magnesium ions are then removed in regeneration cycles, leaving behind only soft water.

Find out more about how a water softener works

Types of water softener

Water softeners typically come in either single cylinder or twin cylinder varieties. When you require a large amount of soft water, perhaps for a big wash after a family meal, you will find the single cylinder system struggles to keep up with demand. Water softeners rely on a two-stage process involving the separation of the calcium and magnesium ions followed by their removal through the regeneration process. When single cylinder systems are forced to treat large amounts of water, the regeneration cycle has trouble keeping up.

Usually, the regeneration cycle is triggered by an electrical timer, which regenerates the system when it is not typically in use (during the night or the working day for example). The result is that hard water will flow from your taps and the regeneration cycle may take 4-5 days to complete and it will waste water and salt in the process. Twin cylinder water softeners work off pressure and can regenerate continuously.

Learn more about single vs twin cylinder water softeners

How much does a water softener cost?

The cost of your Harvey™ Water Softener will vary according to the type and size you choose. However, the savings provided by a water softener can produce a payback within at little as 2 – 4 years. We also regularly receive feedback from our customers that the benefits they experience from using soft water more than justified their decision to invest in a water softener.

We can provide you with a free quote for a water softener, and we also offer a lot of flexibility if you want to try before you buy or simply have a no-obligation demonstration.

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    Do I need to arrange a water softener service?

    Although a water softener is constantly in operation, because there are few moving components, its life is much longer than most other domestic appliances. Your supplier can probably offer to service your system if required. The frequency of servicing or maintenance will depend on the type, age, and usage of the softener. Single cylinder water softeners are likely to require more frequent servicing than twin cylinder systems.

    Read more about water softener maintenance

    Can a water softener be moved?

    Definitely yes. It is as easy as removing a washing machine or dishwasher and can be moved from home to home. In many cases, a water softener has been known to help sell a property as a result of its protection of the hot water system and bathroom sanitaryware.

    Read more about moving with a water softener

    Can a water softener be used with lead pipes?

    When an ion-exchange water softener is installed it is recommended that, as a precaution, all lead pipework carrying soft water should be replaced. Softening the water will not in itself affect the uptake of lead from existing pipework but the disturbance of lead pipework in fitting the softener may do so. Grants may be available for replacement of pipework for households with low income: further information may be obtained from your local authority.

    Will my water bill be affected by fitting a water softener?

    A small amount of water will be used to regenerate the softener, but your water bill will not be affected unless you have a water meter fitted. However, this increased water use may be offset by using less water for cleaning.

    Is soft water suitable for drinking?

    Whether or not softened water is suitable to drink relates to personal preferences and the regulations of your area. Concerns are often raised over the sodium content in the water, which can raise salt levels in a person’s diet. In accordance with regulations, water should contain no more than 200 mg/l of sodium. However, in areas where water hardness is very high, the softening process can be more vigorous and the sodium levels can be large. In such circumstances, it is usually recommended that a hard water tap is installed especially for drinking purposes, though we know many homeowners who drink softened water.

    Will soft water affect my central heating system?

    Soft water will prevent scaling: however, if the nature of your local water supply requires it, or if you have an indirect central heating system, a corrosion inhibitor should be used.

    What kind of water do plants like?

    It is worth checking with your local garden centre. The level of sodium in softened water may be harmful to some plants. Most indoor plants usually prefer rainwater to tap water. It is an unnecessary waste of soft water to use it to supply a garden hose.

    Can soft water be used in an aquarium?

    Softened water may be acceptable. If in doubt, check with your local aquatic supplier.

    What kind of water should be used in car batteries and steam irons?

    Irons can use hard and/or softened water. The guidance given in the manufacturer’s instructions should be followed. Only distilled or deionised waters should be used in car batteries.

    Is soft water suitable for home brewing?

    It varies. Naturally soft or softened water is suitable for wine, brown ale, stout and lager brewed from concentrate kits. Homebrewers who “mash” may require special water treatment.