What is the approximate fresh air ratio of the all air system?

It depends on what kind of building, if it is a place with a large number of people, such as a shopping mall, the ratio of fresh air in the most unfavorable season is 15% to meet the requirements for fresh air, and 12%-15% in the rest of the season.

Summary. Hello dear.

The "air volume" mentioned here actually refers to the "fresh air volume". When we buy a machine, how much fresh air do we need? This depends on the size of the room used and the number of people.

According to the national standard, the number of air changes per hour for ordinary residential buildings is 1 time, and the per capita fresh air volume index of domestic residential buildings is not less than 30m3 h.

Therefore, the size of the fresh air volume of the fresh air system should be the size of the room, or the result of 30 times the number of people. Most of the time, the results obtained by the two methods of calculating the fresh air volume are different, and we should choose the data with the larger fresh air volume. If there are many people, choose according to the number of people.

If the room is large, it will be calculated according to the room size.

How much is the appropriate amount of fresh air in the indoor fresh air system?

Hello dear. What is the appropriate air volume for the fresh air system?

The "air volume" mentioned here actually refers to the "fresh air volume". When we buy a machine, how much fresh air do we need? This depends on the size of the room used and the number of people.

According to the national standard, the number of air changes per hour for ordinary residential buildings is 1 time, and the per capita fresh air volume index of domestic residential buildings is not less than 30m3 h.

Therefore, the size of the fresh air volume of the fresh air system should be the size of the room, or the result of 30 times the number of people. Most of the time, the results obtained by the two methods of calculating the fresh air volume are different, and we should choose the data with the larger fresh air volume. If there are many people, choose according to the number of people.

If the room is large, it will be calculated according to the room size.

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Fan coil unit plus fresh air system is an important form of air conditioning in the water system, and it is also a more common form of air conditioning in private buildings, fan coil unit plus fresh air system is divided into two parts, ** air conditioning fan coil unit and fresh air system, fan coil unit is.

Air conditioning terminal equipment, fresh air system to bear the fresh air load to meet indoor air quality.

Compared with the all-air system, the fan coil unit plus fresh air system is particularly prominent.

According to the use of the room, the start and stop of the fan coil unit is determined, which has the superiority of individual control, and the control is flexible, and the temperature of each room can be flexibly adjusted;

It is easy to realize system partition control, and the cooling and heating load can be divided into several regional systems according to the room orientation, use purpose, use time, etc., and implement partition control;

The fan coil unit is small in size, occupies a small area, is convenient for layout and installation, and is even suitable for the renovation of old buildings;

The fan coil unit plus fresh air system also has the following disadvantages:

The indoor air quality is relatively poor, and it is difficult to carry out secondary filtration and is prone to condensate seepage accidents.

Due to the small static pressure of the fan of the unit, the airflow distribution is limited, and the method itself solves the difficulty of fresh air volume, and is actually used in rooms with a depth of less than 6 meters.

The advantages and disadvantages of the machine coil unit plus fresh air system coexist, reasonable design, suitable equipment selection, correct construction and installation can reduce the defects caused by the fan coil unit plus fresh air system, the above is just to understand the advantages and disadvantages of the fan coil unit plus fresh air system.

Disadvantages, for designers, can learn from each other's strengths; For consumers, they can choose the air conditioning system that suits them.

1. The size you provide is not equal to what you say, which one is the subject of the data you provide?

2. Area of fresh air volume per person This algorithm is ** learned? Since it is the amount of fresh air per person, it should naturally be multiplied by the number of people. Or multiply the area by the unit height and calculate it by the number of air changes. If you multiply the area by the per capita fresh air volume, the dimensions of the units are unbalanced.

3,The exhaust air volume is greater than the fresh air volume, in fact, it is not very accurate,It doesn't matter if the two data are close,The key is that there should be a little negative pressure in the room,In this way, it is convenient to discharge the polluted air in the KTV outdoor。 I guess that's what your predecessors meant.

4. Your calculation method of fresh air volume is wrong (or you didn't explain it), so the fresh air volume you calculated is not right, 25 square meters of house, 3 meters high, 75 cubic meters of volume, ten times of ventilation only need 750 cubic meters h, you miscalculated!

5. The fresh air system itself has a supply and exhaust fan, which has nothing to do with the air duct machine. The fresh air system should not be connected to the air conditioning system, but should be an independent system.

6. If the fresh air system has a heat function, the impact on the air conditioner is not very large, and the air conditioner is enough to enrich about 10% of the ordinary heat load, how do you calculate it?

We are peers, so I just said a few words, and I feel that your concept is still unclear.

1. The calculation of fresh air volume can refer to the code and indoor air quality standard. For your case, you can calculate according to the number of users, per capita greater than or equal to 30 cubic meters of h·per person, you use this number multiplied by the number of people at the same time is about the fresh air volume. You can check the volume of indoor air, because KTV is crowded and smoking, so it can be checked 10 to 12 times according to the number of air changes.

If you take the big number, I estimate that in the end it will be 700 cubic meters per hour, and it will be about the same.

2. Your understanding of the fresh air system is very correct, add a little bit, air conditioning, deals with the temperature and humidity of indoor air, not just temperature. The fresh air system is to remove indoor polluted air, introduce fresh air, and heat ** at the same time, so as to reduce the increase of fresh air load on indoor air conditioning.

1. When there are many people, the fresh air volume can be calculated according to the per capita fresh air volume, and the per capita 30 cubic meters per hour can be calculated.

Second, the fresh air volume and exhaust air volume can be the same, not necessarily positive pressure or negative pressure.

3. The fresh air volume and exhaust air volume of the environment such as smoking should be increased in special occasions.

Fourth, the loss rate of heat and cold capacity, please calculate the enthalpy difference according to the heat exchange ratio.

For example, if there is a building with an area of 30 and a floor height of 3 meters, it is calculated according to the formula "building volume = room area x net floor height x number of air changes" (the national standard air change times are, then the fresh air volume required by the building is 45m hp; If a 30m building is permanently inhabited by 3 people, the fresh air volume required by each person is 30m hp under normal circumstances, and the fresh air volume required by the building is 90m hp; In order to ensure sufficient fresh air, the building needs to select a fresh air system according to the standard of 90m hp fresh air volume.

There are three factors that determine the fresh air volume:

1) Dilute the pollutants produced by the population itself to ensure the required air volume for hygienic requirements;

2) Supplement the requirements of local exhaust air volume or air consumption for indoor combustion.

3) Maintain positive pressure requirements in air-conditioned rooms.

The maximum value of the three can be selected for the fresh air volume.

Number of air changes = room air supply volume Room volume, unit is the hour. The size of the number of air exchange times is not only related to the nature of the air-conditioned room, but also related to many factors such as the volume, height, location, noisy air supply mode and the degree of deterioration of the indoor air in the room.

1.Blindly increasing the number of fresh air ventilation is unscientific, the high number of ventilation means that your air volume is large, and the host you need is also large, the larger the host, the greater the noise, which is a problem;

2.Under certain conditions, the higher the number of air exchanges, the higher the wind speed, and the lower the comfort in winter or summer;

According to the relevant fresh air design code standards, the ventilation frequency of the general home-type apartment is in the villa, and the area with more smoking is selected or the relevant code and standard are used to choose a reasonable ventilation frequency.

1. The essence of all fresh air systems is to improve air quality.

If you want to achieve good results, you must ensure the quality of the installation.

A person breathes 9,000 litres of air a day, 80% of which comes from indoors. Courseware indoor air quality is very important to human health. However, studies have shown that indoor air pollution is 20 times higher than that of outdoor air, and ventilation is the most effective way to improve indoor air quality.

Braun fresh air products are equipped with filters with different efficiencies to filter and purify fresh air before it is sent into the room. Users can choose the corresponding products according to the different needs of the air cleanliness.

Generally, the best fresh air products will be equipped with boiler steam without filtration efficiency, which can filter and purify fresh air before it is sent into the room. Users can choose the corresponding products according to the different needs of the air cleanliness.

The HEPA Funny Filter filters out 99% of the particles that can enter the lungs in the air.

The purpose of fresh air is to improve air quality, send in fresh air, eliminate indoor odor and floating, and maintain constant humidity and oxygen. But when choosing a new fan, you should pay attention to the brand. Some new fans are full heat exchangers are paper-based, which will become moldy after a long time, so it is necessary to choose an all-aluminum exchange core, which not only has a much better effect, but also will not be moldy and smelly.

You can consult me for details. Specializing in home air conditioning and fresh air systems.