The decisive factor here is the width of your hob. Due to air currents in the kitchen, the vapour produced during cooking usually does not rise vertically. The extractor hood should therefore be wider than the hob in order to be able to capture the vapours effectively.
A hob up to 75 centimetres wide needs a hood width of 90 centimetres and a hob up to 90 centimetres wide should have a hood width of 120 centimetres.

First, turn off the electricity in the kitchen, then remove the old cooker hood (if any). Then prepare the installation. Measure the height at which you want to install the cooker hood and mark the spot with a pencil. To draw a straight line, I advise you to use a spirit level.
If you're replacing an older range hood, there's probably an outlet nearby. If it's new, this usually isn't the case, so you should make sure beforehand and get an extension cord if necessary. Otherwise, you can also think about relocating an outlet.
The exact installation of an extractor hood varies from model to model, so please be sure to follow the installation instructions. As a rule, you will need a wall bracket to which you attach the hood, or it is equipped with a so-called wall mounting plate.
Now switch on the electricity in the kitchen and test the cooker hood.
The previous steps were for the installation of a cooker hood with recirculation. If you want to install one with exhaust air, it is also necessary to install an exhaust pipe so that the cooking fumes can escape outside.
If you live in a rented house, clarify the installation with your landlord first, as a hole may have to be knocked in the wall of the house.

As a rule, manufacturers recommend a minimum distance of around 45 to 65 centimetres from the hob. The distance from the hob to the lower edge of the cooker hood is measured here.
However, the maximum distance is not precisely defined. In general, I can tell you that the effect of the extractor hood decreases the further away it is from the hob.

Depending on the model, you have to change the activated carbon filter every four to eight months, as its effect decreases considerably over time. Of course, this also depends on how often you use your cooker hood.
Unfortunately, you can't clean the activated carbon filter. As soon as it no longer performs as it should and doesn't filter the odours out of the air, you have to replace it.

A grease filter gets full quite quickly with regular use and should therefore be cleaned every one to two months.
Usually, filters are dishwasher safe, but some models can't stand the hot temperatures. In that case, you should resort to hand washing or choose a lower temperature setting on your dishwasher.

The power of your cooker hood is given in cubic metres per hour (m³/h). This value tells you how many cubic metres of air the hood can clean in 60 minutes.
The rule of thumb for calculating the optimum output for your kitchen is: length x width x height of the kitchen in metres x 8 = minimum output of the cooker hood in m³/h.
Example: A kitchen measuring 3 x 4 x 2.5 metres requires at least one extractor hood with an output of 240 m³/h.
In the case of island hoods for free-standing cookers, the output can be somewhat higher, as the vapours are distributed more quickly in all directions.

In rooms with a ceiling height of 2.5 metres where a cooking island is installed, so-called island hoods are generally used. These are to be mounted on the ceiling, either with metal cables or rods.
However, if the ceiling is higher than three metres, you should think about another type of air purification, as the effectiveness of an island hood leaves something to be desired at such a height.
As an alternative, you have for example so-called table fans, which are known as downdraft systems. This system is installed directly in the worktop of the island or is already part of the hob.

The exhaust air hose or duct should not have a cross-section of less than 120 millimetres and should not have any uneven pipe bends. This results in high noise levels as well as a lower performance of your cooker hood.
Flat round pipes or plastic spiral hoses are recommended, but these must be laid very tightly.