Setting Up Dishwasher’s Water Hardness Settings

Unlike washing machines, dishwashers need to be set up for the correct water hardness levels. Manufacturers use factory default settings that try to be suitable for the average house in the UK. However, as water hardness varies considerably from area to area this means yours could be set too high or too low.

Have you adjusted your dishwasher’s water hardness settings?

If using all in 1 multi tab detergent -especially in a soft water area you might be able to stop using rinse aid altogether and save money. The majority of dishwashers probably aren’t set up properly but still manage to work ok as far as the owner is concerned. However, if you live in a very hard water area you may experience issues such as poor wash results and damaging limescale build up inside. If you live in a very soft water area you may get excess foaming, or just be wasting dishwasher salt by using too much.


How to set your dishwasher up for water hardness

You will need to follow instructions in your dishwasher’s instruction manual because they will differ from machine to machine. If you don’t have it, you may be able to download one using links on my instruction books and user manuals page because all appliances can be found once you get to a manufacturer’s booklet download page.

Rough explanation of water hardness settings

There are usually two separate adjustments which are easily made. First, as shown in this photo, on the lower side of the inside panel of the dishwasher (usually just above the salt compartment) there may be a small dial. On my dishwasher this has just two settings, 1 and 2. By default they will always be set to hard water, which is fine if you have hard water, but if you are in a soft water areas it can be turned down to number 1.


On my dishwasher there is another “electronic” setting with levels from 1 – 10. My instruction manual lists a chart with recommended settings quoting all possible water hardness ranges. The lowest setting even tells you not to use any salt at all. The way I need to calibrate my dishwasher is to press specific option buttons which put it into the correct mode and simply select which level from 1 to 10 I require. There’s no point describing it here because every dishwasher will be different. Just check your instruction manual.

If you are using Multi-Tab or All In One tablets

If you use multi-tab detergent you shouldn’t need to use water softener or salt so these adjustments aren’t necessary. However, you must check out this article to make sure you have set up your dishwasher so it knows not to use them Have you calibrated your dishwasher for multi-tab detergent?

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How do you find out how hard your water is?

You can check with your water supplier, most if not all should have this information on their web sites – Water company contact details

If you are using Multi-Tab or All In One tablets

If you use multi-tab detergent you shouldn’t need to use water softener or salt so these adjustments aren’t necessary. However, you must check out this article to make sure you have set up your dishwasher so it knows not to use them Have you calibrated your dishwasher for multi-tab detergent?

Update

After carrying out the adjustments in this article I did notice that occasionally there was water left in the tops of some mugs and other items with small indentations in..


I could live with it, but eventually I decided to undo my calibration for multi tabs and add rinse aid back in, which seems to have stopped it. However, I did turn down the small dial in the rinse aid dispenser in the door so that it uses the minimum amount because the tablets were doing 90% of the work. My conclusion is that the 3 in 1 multi tab detergent may not be 100% good enough to do the job alone depending on the brand and quality of the tablets and the hardness of your water.
Our water is moderately hard, if soft I expect I could have completely done away with rinse aid. Experiment with your own settings dependant on your water hardness levels. If you are using these all in one tablets you should not need normal amounts of rinse aid as well.

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