This page continues looking at the effects of hard water and limescale in washing machines and plumbing. It also looks into the use of water softeners and other hard water treatment and removal measures as well as the use of third party anti limescale products such as Calgon.

How limescale and hard water affects washing machines

• Should I use Calgon anti limescale tablets or other such products?
• How can I deal with hard water and remove limescale? Should I use a water softener?
• Is it OK to connect a washing machine to a full scale water softening system?

 

Should I use Calgon anti limescale tablets or other such products?

Here's a quote from a few different washing machine manufacturers -

"Too little detergent results in limescale on the heating element".

This means that using enough detergent should not result in limescale on the heating element. The main advantage of limescale tablets seems to be to soften the water and therefore allow you to reduce the amount of detergent needed but it's advertised as a limescale preventer, which although it is, it's implying it does something extra.

Washing machine detergent already contains ingredients to soften the water and protect the washing machine from limescale. If you use a good quality detergent, and the correct dosage of washing machine detergent for the hardness of your water and the level of soiling on the laundry then you shouldn't need to use anything extra.

Softening the water in your washing machine with Calgon or similar anti limescale tablets will allow you to reduce the amount of detergent you need to use to the level advised for soft water. However, someone needs to do the calculations as to whether the savings in detergent are significantly greater than the cost and hassle of buying and using an extra product.

Severe hard water limescale problems will affect all heating elements in your house where they heat water. This includes kettles, baths, sinks, showers, immersion heaters, dishwashers and washing machines. So if you live in an area where the water is so hard that it causes problems, and you are likely to stay in this area, then you may be better off looking at other methods of softening all of your water rather than just dealing with the problem in the washing machine.

Note: If you live in an area where the water is already soft, softening the water further by using these remedies unnecessarily (which people do because they still get promoted in these areas) can result in poor wash results. Water that is too soft is no good for washing machines as the detergents have difficulty dissolving.

On Calgon's website, they have a feature that checks the hardness of the water in your area. You enter your postcode, and within seconds, you get a graphical representation of the hardness of your water. I was initially impressed with this, and considered linking to it from this section. However, when I entered my own post code, I received a full red bar pointing up to "hard", and the following message

"HARD - We recommend using Calgon in every wash to prevent limescale build up in your washing machine ."

I know we have fairly soft water, so I did wonder if everyone gets this message. I sent them an email pointing this out and asking them to look into it. The facility is clearly faulty (at least with my post code) but as yet, even though they acknowledged receipt of my e-mail, and claimed they would look into it, the erroneous advice is still there over 3 years later.

I contacted Yorkshire water to double check the hardness of my water and they said post codes were an unreliable way of accurately determining water hardness. They offered to send me a free water testing pack. (Most UK water companies will send you a free water testing pack)

Ironically, when mine arrived, it was supplied by Calgon. It consisted of a small strip to dip into the water, which would indicate the hardness of the water. Sure enough, it showed my water is soft.

An email to Yorkshire Water received a reply which said,

"Thank you for your recent email regarding the water hardness in your area. I have contacted our Water Quality Scientist who has advised that the water in your area is classed as Moderately Soft water and is measured at 26.429 mg/l as calcium."

Even considering I am a sceptical person, I find it hard to believe that the message advising the use of Calgon would be given to everyone, regardless of the hardness of their water. This would clearly be a stupid thing to do, but as the service is currently unreliable, and some people may be duped into buying Calgon totally unnecessarily, I am putting the warning about it here.

Clearly the makers of Calgon want as many people to use their product as possible. The chances are that the results I got from their web site are a genuine mistake although they have known about it since my e-mail on January 9th 2003 and the mistake is still there in 2006. (Update: It's still telling me I have hard water and need to use Calgon in 2009! I've also moved to another area where my water authority tells me our water is "moderately hard" but the Calgon site tells me it's hard and shows it at the top pf their scale). I contacted them again in April 2008 and they just say my water is hard according to how they measure it (HARD = above 200 ml/g as calcium carbonate) but my water was not hard and my water company confirms this.

Testing the tool using a Lake District post code, which is known for having the softest water in the UK the tool does report back that water there is soft - but still advises, "Soft: We recommend using Calgon to prevent limescale build up on your clothes". I recommend if you want to find out how hard your water is you shouldn't trust Calgon to tell you. Check at your local water authority web site - UK water companies web sites and telephone numbers (please let me know if this link breaks as web sites keep moving things)

Summary regarding Calgon tablets (or similar products)

Products such as Calgon don't do anything that proper washing machine detergent doesn't do (as long as you use the correct amount) although they do -

1. Help protect against under dosing
2. Soften the water allowing you to use the amount of detergent recommended for soft water in a hard water area

The last effect could potentially save money if the money saved by reducing the amount of washing detergent is greater than the cost of the Calgon (or similar) tablets. I don't know of anyone that's done the appropriate tests to determine this but Calgon claim you could save up to 25% of the amount of detergent required. 25% is presumably the best case scenario, it depends how much the tablets cost compared to how much you save in detergent.

Some reputable washing machine manufacturers recommend Calgon, but then they are presumably recommending it because they would rather people use Calgon tablets and keep their washing machines free of limescale (and working) even if it is a short-sighted solution or if it's only effective for a small percentage of their customers. Maybe they know if the washing machine packs in due to hard water many people will just blame the washing machine? They aren't looking at it from the bigger-picture point of view, which someone suffering from bad limescale problems may well be better off doing.

Using anti limescale tablets in your washing machine can only deal with the effects of limescale in your washing machine. If these effects are so bad, then what about the rest of your plumbing and appliances?

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How can I deal with hard water and remove limescale? Should I use a water softener?

If you want to try and tackle hard water and limescale problems at the source instead of expensively fighting the symptoms in individual appliances, you can use either a water softener system or try one of the much cheaper electronic water conditioning devices.

The main benefits would include

• Removing and preventing limescale
• Protecting appliances such as washing machines, kettles, dishwashers, hot water cylinders and pipework
• Save on detergent as the water feels softened
• Potential improvements in skin conditions such as eczema

Limescale treatment

There are many hundreds of sites selling hard water treatment devices and it can be pretty confusing. If you are interested in hard water treatment then Scalewatcher is a UK company and their web site is well designed and informative. The use of this type of electronic water "conditioners" has people divided as to their effectiveness. Some claim there is no proof that they work, while many companies selling them have reports from laboratories and universities that show that  they do. All I can say is that most companies have full money back guarantees and plenty of letters from satisfied customers on show. Scalewatcher have been mentioned (not negatively) as a supplier of electronic water softeners by Which? and they have sold over 100,000 units.

(If you want to spend more, on more conventional water softeners then you need to look into ion exchange water softeners and reverse osmosis water softening systems).

While clicking any external links, hold down the shift key to read the external site in a separate window. You can then save your place on Washerhelp.

If you have hard water problems you have several choices - (External Scalewatcher link)

Why use Scalewatcher? - (External Scalewatcher link)

 

Is it OK to connect a washing machine to a full scale water softening system?

Some washing machine manufacturers advise against connecting their washing machine to an full artificially softened water supply (not the electronic water "conditioners" mentioned above) as it can make the water too soft for washing. If you don't reduce the amount of detergent it can result in oversudsing, but less detergent can give poorer wash results.

Modern washing machine detergents can be less effective in very soft water because the detergent does not dissolve as well. This can cause detergent deposits on laundry.

Summary: Using a washing machine with an artificially softened water supply should not damage the washing machine, but wash results can be affected due to the detergent not dissolving properly and leaving detergent residue on laundry. This may be counteracted a little by using an extra rinse option on the washing machine if available. This advice may also help If you live in a (naturally) very soft water area. My current understanding is that this advice is relevant to chemically softened water rather than electronically conditioned devices mentioned above, which claim to condition the water and prevent limescale build up rather than physically soften water.

More on next column ...

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