Bialetti Safety Valve M8 for Stove Top Espresso Coffee Maker Moka

• The Moka valve is not an ornament: rather, it is a useful and precious component, which guarantees safety and an excellent coffee.
• The Moka valve, often ignored, is extremely precious in order for the coffee maker to function well.
• Opening the valve allows the steam to escape without raising the pressure inside the bottom chamber too much (only if necessary).
• Not everyone knows that the valve also acts as a measuring cup: the right amount of water to add in the Moka should reach the valve itself.
• The valve should be cleaned and maintained regularly.

• Brand Bialetti
• Type Safety Valve
• Appliance Coffee Maker
• Thread Size M8 x 0.8
• Thread Length 4 mm
• Spanner Size 9 mm AF

The importance of details

The devil is in the details. It is often the smallest things, the particularities, that make all the difference. This is also the case in regards to the preparation of a good coffee, a ritual in which all the steps and every single component play a fundamental role. Among all, one of the most important elements is the Moka valve. Often ignored, it is vital not only for the quality of the coffee, but also for the safety of those who prepare it.

A matter of pressure

The valve was born with the invention of the Moka Express in 1933. It is a safety valve positioned on the bottom chamber. To better understand the importance of the valve and its use, we need to take a step back and illustrate step by step how the Moka works.

• When the coffee maker is placed on the stove, the water eventually reaches boiling temperature.
• At this point, the steam increases the pressure in the bottom chamber and pushes the water through the grounds into the funnel filter.

The coffee is obtained thanks to this virtuous union of elements and processes. Hosted by the top chamber it is now ready to be savored.

The Moka valve is a safety mechanism

If, for some reason, the water fails to pass through the filter, the pressure inside the bottom chamber would begin to increase rapidly. This can happen, for example, when:

• the coffee is ground too finely;
• the coffee has been excessively pressed into the filter;
• the temperature of the heat source is too high.

This is where the valve of the Moka comes into play. It must open when the pressure is too high. By doing so, it allows the steam to escape regularly, without causing any damage. In short, the Moka’s safety valve provides security. Hence, it should only intervene when the coffee maker is used under abnormal operating conditions.

The right amount of water

A long-standing and debated question: how far can you fill the bottom chamber for a state-of-the-art coffee? The Moka valve can come in handy to answer this dilemma. Another important role of the valve is that it acts as a "measuring cup". Its position on the bottom chamber is not accidental. Rather, it indicates to those who prepare the coffee the correct amount of water to use. The only exception is for some special coffee pots that are already equipped with a measuring cup. Ideally the water should reach just below the safety valve.

By contrast, if you drown it completely, there is a risk that it will not work properly. Moreover, if the water goes beyond the filter, thus mixing with the grounds, it would hinder the gradual rise of the water, compromising the final result. Be that as it may, once the coffee has been prepared, it is normal that a small amount of water remains inside the bottom chamber.

The Moka valve needs to be cleaned: here is how

The Moka valve, therefore, is not a decoration or a mere design element. Rather, it is a very important component for the correct functioning of the coffee maker. It guarantees safety and plays a part in the making of an excellent coffee.

Consequently, it is necessary to keep it clean and maintain it regularly. For example, using tap water to make coffee brings with it the risk of limescale deposits obstructing the hole in the valve. The resulting danger is that it could get clogged.

We have seen that natural and effective remedies can be used for a good cleaning of the Moka pot. The same goes for the valve. To be specific, one can simply use hot water to clean the Moka valve. To avoid limescale obstructions, simply move the piston that comes out of the valve along its axis when washing it. To ensure the Moka functions correctly, it is recommended to repeat this checkup periodically.