Is the larger the exhaust volume of the range hood, the better? Let’s take a look at the new saying!

Industry statement 1

What is range hood air pressure?

Wind pressure refers to the static pressure value when the exhaust air volume of the range hood reaches 7m?/min. The state stipulates that the index value is greater than or equal to 80Pa. The greater the wind pressure value, the better the range hood can resist backdraft. The stronger the ability, the better the smoke exhaust effect. If the exhaust pipe is long, far away from the building flue, and located on a higher floor, greater wind pressure is needed to ensure that the smoke is discharged and prevent the oil smoke from being poured back. Generally, the air pressure of range hoods on the market is between 240Pa and 340Pa, which is relatively suitable.

What is the exhaust volume of a range hood?

The exhaust volume of the range hood refers to the exhaust volume of the range hood per unit time when the static pressure value is zero. Generally speaking, the state stipulates that the index value is greater than or equal to 7m3/min. The larger the exhaust volume, the more quickly and promptly a large amount of oil smoke in the kitchen can be sucked out. Many industry professionals believe that the general range hood exhaust volume is 12 to 15 cubic meters as the best and most suitable.

The ability to absorb oil smoke depends on how much negative pressure the range hood can generate in the area where oil smoke is generated on the stove. It also depends on how large the exhaust volume is and how efficient it is at exhausting it. , it depends on the size of the wind pressure. Theoretically speaking, if the turbine and inner cavity are properly designed, generally the larger the exhaust volume of the range hood, the greater the wind pressure will be. So in a sense, the two are complementary and should not be viewed separately.

What is the reason why the range hood has poor smoking effect?

1) The installation location is too high;

2) Use public flue;

3) The windows are opened too much and the wind is too strong. Convection is formed to blow away the oil smoke;

4) The filter is too dirty, which affects the smoking effect;

5) The exhaust pipe is too long or turns too much and the smoke pipe is deformed;

6) Insufficient voltage.

Industry statement 2

Large exhaust volume is not the only criterion for a good hood

The fume and exhaust gas generated by kitchen cooking is an important source of household pollution, and many consumers Consumers complained that the expensive range hoods of big brands cannot absorb the oil fume completely, and the biggest pain point for consumers is that the range hoods "cannot suck cleanly"!

The "top suction" with "large suction power" praised by industry leaders "Type" range hood, using aerodynamic principles, has done useful research and promotion in optimizing the volute structure, increasing the exhaust volume, increasing negative pressure, etc., which is commonly known as "large exhaust volume".

Is a "large exhaust volume" hood a good one? Can it solve consumers' pain points and smoke clean oil smoke?

Research shows that the effect of oil smoke exhaust is related to the following factors. :

1. The suction power is high and the fume suction and exhaust effect is good. For hoods with the same structure and appearance, this view is valid.

2. The negative pressure area is low and the oil fume suction and exhaust effect is good. OK.

"Negative pressure" means that the turbine rotates at high speed, forming a low pressure area at the air inlet of the hood, and the pressure difference prompts the oil smoke to be quickly introduced into the volute.

The experimental results show that cooking. When stir-frying, the oil smoke rises like a "mushroom cloud". The oil smoke rises 300mm straight up from the port of the pot, and then quickly mixes with air to form an "umbrella cover". At this time, the oil smoke mixes with a large amount of air, and the volume quickly increases. It is most difficult to absorb oil fume from a machine. Therefore, the "golden capture area" for oil fume pollution is the height of 300mm between the air inlet of the hood and the pot port.

Big names in the industry promote "top-suction" range hoods. The advantage of large suction power is that the cover surface is large and can trap oil smoke;

The disadvantage is that the "negative pressure zone" is far away from the pot, and the 550mm super long oil smoke rising path is not the same as the "golden capture area" of oil smoke. Departure, more fresh air envelops the oil fume and inhales it. The insufficient exhaust capacity of the hood will cause some oil fume to spill out. This is also the reason why big brands strive to increase the exhaust volume to make up for the structural defects of the top suction machine. This is a passive control behavior. . In addition, the horizontal convection air will also push some oil smoke to escape, causing pollution!

Therefore, the suction and exhaust effect of the range hood is related to the distance between the "negative pressure" area and the pot.

3. The three-dimensional smoke collection structure is good and the oil smoke suction and exhaust effect is good.

When cooking, the biggest source of pollution comes from the moment of "stir-frying". A large amount of oil smoke rises, and the hood cannot resist it, causing the oil smoke to overflow. The smoke collection structure is to "contain" the oil smoke that cannot be inhaled for a moment, and then inhale it to avoid pollute.

The "side-suction" range hood that has become the mainstream in recent years has the advantage that the "negative pressure" area is close to the pot, and the suction and exhaust effect is obvious. The oil fume will "rush to the top" and escape. At the same time, the four-sided three-dimensional air inlet structure of the side suction machine will suck in more fresh air, thus affecting the suction and exhaust of oil fume per unit time.

Therefore, the suction and exhaust effect of the range hood is related to the three-dimensional "smoke gathering" structure.

The above explains that "large exhaust volume" does not mean a good hood. Only hoods that meet the requirements of "large suction power", "golden negative pressure zone" and "smoke collecting structure" at the same time can solve the problems faced by Chinese people. Only the oil smoke pollution caused by the hot cooking habit can solve the health threat of oil smoke to consumers and the pollution to the home. Only brands that truly understand the pain points of consumers and work hard for them can be proud of the world.

Industry statement three

There are three performance indicators of range hoods:

1. Generally, air performance indicators will be marked on hoods, including air volume (discharge per unit time). The air volume is usually measured in cubic meters/minute in China), wind pressure (in Pascals), and total pressure efficiency (the ratio between the energy consumed by the hood and the air volume and wind pressure, expressed as a percentage); < /p>

2. Odor reduction degree: This is an indicator that reflects the ability of the range hood. It is related to human health and is divided into normal odor reduction degrees (the smoke exhaust effect within 30 minutes, the national standard requires more than 90%) , the smoke exhaust effect within 3 minutes of instantaneous odor reduction, the state requires more than 50%);

3. Grease separation, which refers to the ability of the range hood to separate grease and smoke, and is an environmental protection indicator , national standards require oil separation to be greater than or equal to 80%.

From the analysis of these indicators, everyone should understand that it is wrong to choose a range hood for the kitchen based solely on air volume or air pressure. From a health perspective, odor reduction is very important; for the overall environment, Grease separation is also very important. Some people say that the air volume of the range hood in our home is very large, which can reach 17 cubic meters per minute. However, if there is no wind pressure, no matter how high the air volume is, there is no way to suck out the oil smoke. Your range hood is at best a large exhaust fan.

Is the range hood the only factor that determines the smoke exhaust effect? wrong!

Both the installation and the flue environment directly affect the smoke exhaust effect

How much influence does the public flue have on the smoke exhaust effect of the range hood? Theoretically speaking, the flue environment will restrict the effectiveness of the range hood in each family. For example, low-floor users who live in high-rise buildings should choose a range hood with higher wind pressure so that they can effectively discharge the fumes into the public ducts.

Whether the installation is professional or not is also a major factor that affects the effectiveness of the hood. For example, the farther the opening in your kitchen is from the hood, the worse the effect will be. The more corners there are, the worse the effect will be. Another example is whether the mesh size design is reasonable. The first mesh of the hood is where you can see it. There is the filter, the second one is in the turbine, and the third one is in the flue. The mesh holes of these three meshes should be smaller one by one, so as to ensure that the oil fume is effectively discharged.

Are side suction range hoods necessarily better? wrong!

It has safety hazards

I think there is a misunderstanding about side range hoods. It seems that the closer they are to the stove, the better. In fact, this has safety hazards. Some side-suction range hoods that cannot separate oil fumes are likely to cause fires if installed too low. I heard a while ago that a family had a side-exhaust range hood installed too low, causing the stove fire to burn the oil pot of the side-exhaust range hood and a fire broke out.

Choose a range hood based on your own kitchen conditions

More than 10 years ago, manufacturers promoted that the more powerful the range hood, the better the effect of absorbing range hoods. Now it seems like a joke. There are other jokes circulating on the market now: For example, the greater the air volume, the better the smoke exhaust effect.

Experts’ advice on purchasing range hoods is to choose a range hood based on the actual conditions of your house:

1. The bigger the air volume, the better. In general, the air volume of a range hood for daily cooking is enough at 11-12 cubic meters per minute. If it is too high, the heat energy of the gas will be wasted;

2. Choose the air pressure and air volume. The living conditions of your home also matter. If you live on the fifth or sixth floor of a high-rise building, it is recommended to choose a range hood with high wind pressure, otherwise the smoke exhaust effect will be poor;

3. The temperature drops and the grease separates These two indicators may already be marked on newly launched products, so pay more attention to the values ??of these two indicators.