Table of contents:
- The first decision: recirculation or exhaust air operation?
- Goes anytime, anywhere: extractor hood with air recirculation hood
- The exhaust hood - what you need to know
- Which hood type suits me and my kitchen?
- Performance of extractor hoods
- Interesting facts about filters for extractor hoods
- Bind odors - with activated carbon filters
- Wall hoods - with air circulation or exhaust system
- Free head: vertical extractor hoods
- Space saver: extractor hood as a base
- Extractor hood down
- Further criteria for the purchase of an extractor hood
- The volume level
- Lighting and usability
- Energy efficiency of extractor hoods
- Good to know: extractor hoods in the test
- Installation of an extractor hood: how it works
- Specialist tips: Clean the extractor hood
They suck in the cooking fumes in the kitchen - and filter fats and odors: extractor hoods are a practical and hygienic standard in the kitchens in Germany. Anyone who equips their kitchen with a new extractor hood needs a quantum of basic knowledge before making a decision - we will give you an overview of the different hood types and give tips on installation, filtering and cleaning.
Whether fish, onions or bouillon - many scents stimulate our appetite while cooking. After eating, however, we often perceive them as gnats and bother us with swathes of fat on furniture and walls. An extractor hood above the hob cleans the air from the fat using a grease filter and improves the indoor air. This is easy on the nose and also saves a lot of work when cleaning. When renovating the kitchen, but also when moving or building a new building, it is worth taking a closer look at the choice of the right extractor hood.
The first decision: recirculation or exhaust air operation?
Basically, there are two types of extractor hoods - those with circulating air and those with exhaust air operation. While the filtered and cleaned air from the cooking mist is channeled back into the room air with a recirculation hood, an exhaust hood guides it through a ventilation shaft to the outside. Which variant you choose for your kitchen depends largely on the structural requirements of your kitchen, but also on the type of heating and other factors. A compromise of many manufacturers are so-called combi hoods, which combine the recirculation and exhaust air operation with each other and whose ventilation system, recirculation air or exhaust air, can usually also be used individually - depending on the available options.
Goes anytime, anywhere: extractor hood with air recirculation hood
To operate an extractor hood with a recirculation system, a socket is all that is needed to connect it. The hood draws the cooking vapor through a grease filter made of fleece or metal and blows the cleaned air back into the room. Structural changes are not necessary. For optimal air performance, fleece filters have to be replaced two to four times a year, because once they are soaked, they lose their effectiveness and can easily catch fire. Metal filters, however, can be cleaned in the dishwasher. Many hoods with a recirculation system also have activated carbon filters, which have the function of binding odors.
The exhaust hood - what you need to know
In the extractor hood, too, a fan sucks the cooking vapor and blows it through a filter to which the fat particles adhere. However, the smells and the filtered air disappear into the open air through a ventilation shaft - this usually results in better indoor air more quickly, is quieter in operation and there are no additional costs due to any necessary activated carbon filters. However, there must be appropriate structural requirements for the exhaust air operation in the kitchen. If you are building a new one, you have to pry open the outer wall, lay a pipe or use a fan in the window pane. Conversely, this can lead to heat loss in the cold season and does not work everywhere. The complex installation must be weighed individually against the better air performance.
For safety reasons, exhaust hoods should not be installed if the apartment has gas heating, an oil or coal stove or a gas heater, because the hood creates a strong negative pressure that removes oxygen from the flames. As a result, toxic combustion gases can get into the kitchen instead of being drawn out through the fireplace. It also becomes problematic if the kitchen does not allow sufficient fresh air supply - in this case, whether tenant or owner, you should contact the chimney sweep and ask whether you can operate the exhaust hood at the same time as the heaters.
Which hood type suits me and my kitchen?
If you already know whether you want to and can operate your cooker hood with a recirculation or exhaust system, you need to be clear about the desired performance and the filters used. It is often claimed that ventilated hoods are less effective than ventilated hoods because they channel the indoor air back into the kitchen instead of transporting the haze outside. In fact, however, the performance of the extractor hood is a decisive criterion: a powerful recirculation hood can clean the air better than an extractor hood with exhaust air operation and a low wattage.
Clean your cooker hood regularly. This is the only way it can work reliably at full power and for a long time.
Photo: iStock / fizkes
Performance of extractor hoods
The “air output”, ie the ability of an extractor hood to move and exchange the air, is given in cubic meters per hour. The higher this value, the more air can be moved within the same time - and the better the ventilation of the kitchen. Conversely, an activated carbon filter, which is only used in recirculation mode, can reduce the performance of the ventilation, but in the end result in a better odor result. As a rule of thumb, the room air should be exchanged twelve times an hour. So determine the volume of your kitchen (length x width x height, in cubic meters) and multiply the result by the air exchange rate, which should be a minimum of 6 times and a maximum of 12 times the kitchen volume.
Interesting facts about filters for extractor hoods
Before you decide on a hood type and a certain brand, pay attention to the filters used for the respective model. Metal filters should be multilayer, close-meshed and also dishwasher-safe so that you can clean them easily and easily at any time. You can test the quality of the grease filter with a water spray bottle by observing whether and how much water escapes from the opposite side when spraying - the less, the better. Also compare the prices of filter fleeces so that you can estimate the costs that will arise if you have to replace them regularly.
Bind odors - with activated carbon filters
Activated charcoal filters are available for recirculation hoods for optimum odor control, but at the same time they reduce the air output of the extractor hood. The filling quantity of the activated carbon granulate is based on the suction strength of the fan of your extractor hood and must therefore exactly match the model that you use in your kitchen. On average, activated carbon filters for the extractor hood last 3 to 4 years before they need to be replaced - in case of doubt, let your nose decide! There are now a few manufacturers, such as Miele, who offer washable and regenerable activated carbon filters for their own hoods - but this is not the standard.
Wall hoods - with air circulation or exhaust system
Wall-mounted extractor hoods can often be found in individual and modular kitchens, which means when there are no wall cupboards and no superstructure above the hob. The wall hood, mostly made of stainless steel, can be easily attached to the wall in pure air recirculation mode and operated with electricity - in this case, insert additional activated carbon filters to absorb odors and regularly ventilate your kitchen. If, on the other hand, you have a ventilation duct or an exhaust pipe in the wall, you can also use the wall hood in exhaust air mode. If you do not have this structural requirement, you can also lay such a pipe in neighboring rooms and make ventilation possible.
Free head: vertical extractor hoods
Just as with the wall hoods, the following also applies to vertical extractor hoods: recirculation and exhaust air operation are equally possible and depend on the conditions in the kitchen and apartment. Due to their vertical orientation, these hoods are also called "head-free hoods" because they allow more freedom of movement when cooking. There are often more versatile designs than the conventional stainless steel wall hood. Otherwise, when buying a vertical extractor hood, the same technical criteria must be observed as for a regular wall hood.
Space saver: extractor hood as a base
Built-in or undercounter hoods are particularly suitable for full kitchens, because they are extremely space-saving because they can be mounted directly under a cabinet with a small width of approx. 60 cm. They are available in both recirculated and exhaust air modes, but they are set to recirculated air mode as standard. The filter performance is not always satisfactory with this type of hood, the purchase of an activated carbon filter may make sense in recirculation mode. They are comparatively inexpensive and, depending on the model and manufacturer, are usually also low-noise and have sufficient lighting. Due to their easy assembly, undercounter hoods offer a big plus especially for mini and single kitchens.
Extractor hood down
A variant of the conventional extractor hood, which is located above the hob, is the extractor hood downwards. The extractor hood is integrated directly into the hob and draws in cooking fumes, greases and smells on the spot - provided the pots are not too high. This solution is rather rare due to the insufficient suction power and reduces the size of the hob - but it sometimes makes sense for free-standing cooking islands.
Further criteria for the purchase of an extractor hood
When the decision for the right hood type for your kitchen has been made, there are a number of other quality features that you should think about when choosing your extractor hood: from operating volume to energy efficiency. We present the most important purchase criteria below.
The volume level
Extractor hoods are known to produce noises from the fan and their motor, which make other acoustic activities such as entertaining or listening to music or programs difficult when cooking and roasting. When deciding on a new extractor hood, you should not only pay attention to the model and price, but also to the maximum operating volume of the extractor hood, which is usually given as a decibel number in the product information. Hoods with a value of 50 to 60 decibels are generally classified as quiet and quiet, whereas extractor hoods with a value of over 70 decibels are perceived as loud and noisy. Some hood manufacturers also state the operating volume in the terms "sound power" and "sound pressure". The sound pressure defines the perceived volume.
Lighting and usability
In addition to the ventilation function, extractor hoods have integrated lighting for cooking as standard. Two LED lamps are usually more useful than just one for complete hob lighting. Before you buy, test the operability of the ventilation or suction strength controller and consider whether you need a remote control for your extractor hood or not. With some hood types, the hob is also networked with the extractor hood, so that it automatically starts up when there is cooking steam.
Energy efficiency of extractor hoods
Like all electrical appliances, extractor hoods differ in energy consumption and are divided into efficiency classes A + (very energy-saving) to F (hardly or not at all energy-efficient). There are hardly any differences in price. Experts recommend paying attention to the information on air flow and the degree of grease separation in the energy label. A low energy efficiency class ensures higher costs in the long term, it is said.
Good to know: extractor hoods in the test
In a broad test comparison, Stiftung Warentest compared around 21 cooker hoods per operating mode - recirculated air and exhaust air - in 2016. The test results of a total of 42 extractor hoods can be called up as an online report and address all important criteria such as performance in fat, odor and steam removal, handling, energy efficiency and safety. The hoods from Miele received the best ratings in both operating modes: the test winner was the two Miele exhaust hoods DA 416-4 and DA 429-4 (rating "very good").
The Miele PUR 97 W extractor hood won the class in the horizontal hood category.
Installation of an extractor hood: how it works
You can commission a specialist to assemble an extractor hood or, depending on your skill, also do it yourself. Make sure that the selected hood protrudes about 10 cm from the cooking area on both sides of the hob so that vapors and fats are optimally collected. Flat screen hoods are therefore ideal. Depending on the type of kitchen, you can also have the extractor hood installed in or between wall cabinets.
Mount the extractor hood as close as possible to the outer wall. The following applies to extractor-operated extractor hoods: kinks in the pipe connections between the hood and the outlet and long distances increase the resistance that the air has to overcome - this makes it difficult to effectively discharge cooking vapors and rumors outside. If the device hangs far from the outer wall, select a fume cupboard with a larger delivery volume.
Metal filters can be easily cleaned in the dishwasher and are then fully operational again.
Photo: iStock / artursfoto
Specialist tips: Clean the extractor hood
Depending on how often and intensively the food is cooked, it makes sense to clean the extractor hood approximately every three weeks. Individual parts can often be cleaned in the dishwasher. You can also manually remove dirt from your cooker hood with a washing-up brush, hot water and detergent. Also clean the interior of the hood, because contaminated grease filters are almost ineffective.
To clean the metal filters in the dishwasher, choose an intensive program and only clean the filters without any additional dishes - in the event of heavy soiling, in a horizontal orientation. When using air recirculation, also remember to replace possible activated carbon filters.