My Avent steriliser's heating plate shows white/brown spots

In the UK, hard water may contain the equivalent of 200 mg of calcium carbonate (limescale). Hard water also has a high mineral content, which can affect the colour of limescale.

When water is heated, dissolved calcium and magnesium bicarbonates break down and form solid limescale.

Limescale from hard water is usually white, but traces of other minerals or metals can change its colour. For example, copper traces in plumbing can make it grey, green or blue. Rust from water pipes can make it brown or black.

Important: Always unplug the steriliser and allow it to cool completely before descaling.

Choose one of the following methods.

Method 1: White vinegar solution

1. Pour 100 ml of white vinegar mixed with 200 ml of cold water into the steriliser.
2. Leave the solution in the steriliser until the limescale has dissolved. Do not switch on the appliance.
3. Empty and rinse the steriliser.
4. Run a full cycle with the baskets or racks inside and the lid on, using exactly 90 ml of water.

Method 2: Citric acid solution

1. Mix one sachet (10 g) of citric acid with 200 ml of water.
2. Pour the solution into the empty steriliser. Do not fit the lid.
3. Switch on the appliance for 1–2 minutes.
4. Unplug the appliance and leave the solution for 30 minutes.
5. Empty and rinse the steriliser.
6. Run a full cycle with the baskets or racks inside and the lid on, using exactly 90 ml of water.

Do not use a descaling solution other than white vinegar or citric acid.

Important: Always unplug the steriliser and allow it to cool completely before descaling.

1. Pour 80 ml / 2.7 fl oz of white vinegar (5% acetic acid) and 20 ml / 0.7 fl oz of water into the water reservoir.
2. Leave the solution in the water reservoir until the limescale has dissolved.
3. Empty the water reservoir and rinse the heating plate with clean water. Empty it again, then wipe the plate with a damp cloth. Do not rinse it under the tap.

Repeat this process as often as necessary.

Important: Always unplug the steriliser and allow it to cool completely before descaling.

1. Pour 60 ml / 2 fl oz of water and 30 ml / 1 fl oz of white vinegar (6–8% acetic acid) onto the heating plate.
2. Leave the solution on the heating plate until the limescale has dissolved. This takes around 20 minutes. Do not leave it for longer than one hour.
3. Empty the heating plate, rinse it thoroughly and wipe it with a soft cloth.

Important: Always unplug the steriliser and allow it to cool completely before descaling.

1. Pour 12 ml (2.5 tsp) of white vinegar (5% acetic acid) and 120 ml (4 oz) of water into the water reservoir.
2. Place the small basket on the base, then place the lid on the basket.
   Note: The small basket helps prevent hot liquid from splashing out.
3. Press the power button to switch on the appliance.
4. Let the appliance run for five minutes, then press the power button to switch it off.
5. Allow the appliance to cool for around five minutes.
6. Empty and thoroughly rinse the water reservoir.
7. Remove any remaining limescale with a sponge, then rinse again.
8. Wipe the base with a damp cloth.
   Note: Descaling results may vary depending on water hardness and how often you descale. Repeat the descaling cycle if needed.
9. Rinse the small basket and lid to remove the vinegar solution.

You can also use citric-acid-based descalers. Do not use other types of descaler.

Important: Always unplug the steriliser and allow it to cool completely before descaling.

1. Pour 12 ml (2.5 tsp) of white vinegar (5% acetic acid) and 120 ml (4 oz) of water into the water reservoir.
2. Place the small basket on the base, then place the lid on the basket.
   Note: The small basket helps prevent hot liquid from splashing out.
3. Turn the on/off button to Sterilise mode, then press it to switch on the appliance.
4. Let the appliance run for five minutes, then press the on/off button to switch it off.
5. Allow the appliance to cool for around five minutes.
6. Empty and thoroughly rinse the water reservoir.
7. Remove any remaining limescale with a sponge, then rinse again.
8. Wipe the base with a damp cloth.
   Note: Descaling results may vary depending on water hardness and how often you descale. Repeat the descaling cycle if needed.
9. Rinse the small basket and lid to remove the vinegar solution.

You can also use citric-acid-based descalers. Do not use other types of descaler.