What is the difference and advantages and disadvantages of air cooling and direct cooling

Both air cooling and direct cooling have their own advantages and disadvantages.

The advantages and disadvantages of air cooling and direct cooling are listed below.

1. The demarcation point between air cooling and direct cooling is about 300 liters, and air cooling with large volume and multiple rooms has advantages.

2. With large volume and many compartments, air cooling has an absolute advantage in cooling distribution. If direct cooling is adopted, there will be technical obstacles, and it is not easy to achieve. If you want to make more rooms, you will sacrifice some performance. Therefore, when you see some large-volume, multi-chamber (even drawer doors) direct-cooling refrigerators on the market, don't believe it. This kind of product is not uncommon on the market, and it is mostly concentrated in small brand products, mainly sold in the third and fourth markets. It can also be seen in the periphery of some big cities and in home appliance wholesale markets.

3. The air-cooled refrigerator has more fans to supply air, so the indoor temperature of the refrigerator is relatively average, there is no big temperature change, and the cooling effect is naturally better, but also considering the function of the fan and the complex circuit design, the air-cooled type The energy consumption and noise of refrigerators are much higher than direct cooling refrigerators.

4. Cooling speed The air in the direct cooling box has natural convection, and the freezing speed is slow. The air in the air cooling box has forced convection by a fan, and the freezing speed is fast.

5. Since there is no electric fan, the direct cooling type will not generate additional noise and power consumption, and will not cause drying on the surface of the food due to blowing.

6. Air cooling is a forced circulation of cold air, so the cooling speed is fast and the temperature balance is good. This is its inherent advantage, and direct cooling cannot be compared. The direct cooling relies on natural convection, so the temperature balance is relatively poor, and the cooling rate is relatively low.

7. The inherent defrost cycle of air cooling, fans and multiple compensation heaters inside lead to higher power consumption and noise than direct cooling refrigerators, about 15%~25% higher. Therefore, under similar circumstances, air cooling definitely has no advantages in these two aspects. It is clear from the national and international refrigerator performance and energy consumption level standards. Therefore, it is boasted that air cooling has lower energy consumption and less noise than direct cooling, but it is not a comparison under the same conditions.

8. The manual defrosting of direct cooling is really annoying. The so-called micro-frost design is only a whole drawer for freezing, which reduces the air flow in the door opening box to reduce frosting. Even so, defrosting is generally required for half a year. If the number of door openings is small, it can be extended, and vice versa. Frost can also become severe if the door is poorly sealed or aged. The number of defrosting will increase with the use of time.

9. Air cooling Due to the forced circulation of air, the smell will move in all rooms. There are also some dual-system air-cooled refrigerators, which separate the freezing and refrigeration, and the situation is better.

10. The air-cooled refrigerator continuously brings the moisture in the box to the evaporator, and then flows away when defrosting, which brings dry consumption in the box, which is not conducive to preservation, which is also an inherent disadvantage of air-cooling. Although there are some so-called fresh-keeping technologies, but in a small area (such as a relatively sealed space), cold air is not allowed to enter, and only flows around. The space is actually close to natural convection, but it is direct cooling of the small space. That's it.

11. To put it simply: the air-cooled refrigerator has a fan to defrost and does not freeze, and the direct-cooled refrigerator has no fan, freezes, and needs to be defrosted by hand

12. There is no frost in the air-cooled refrigerator. This is because an evaporator is set inside, and then the cold air is sent to various positions of the refrigerator through fans and air ducts. The temperature rises for a short time, and the cooling is resumed immediately after defrosting. Since its evaporator is hidden inside the refrigerator, we can't see the frost it produces.

13. The food in the direct-cooling refrigerator is in direct contact with the evaporator of the freezer. The humidity of the air is high, and the frozen items are easy to stick together, which is not easy to access; taste. Because the frozen food does not directly contact the evaporator, the air-cooled refrigerator will not cause stickiness and is easy to access.

14. Failure rate The failure rate of direct cooling refrigerators is low, and the maintenance rate of indirect cooling refrigerators is high. There are more fans and defrosting parts than direct cooling refrigerators.

As mentioned above, air cooling and direct cooling have their own advantages and disadvantages, which can be summarized as follows:

Advantages of direct cooling:

1. The direct cooling refrigerator has a simple structure, a relatively low failure rate, and low costs lead to low prices.
2. The refrigeration principle is simple and direct, and relatively speaking, it is more energy-saving and power-saving.
3. Natural convection in the confined space, the air humidity is high, and the moisture of the food is not easy to lose.

Disadvantages of direct cooling:

1. The problem of frosting causes users to defrost manually, which is time-consuming and labor-intensive and unwelcome.
2. The frosting problem will seriously affect the heat-absorbing refrigeration of the evaporator, and the refrigeration efficiency will drop significantly.
3. Natural convection makes the cooling capacity of the refrigerator unevenly distributed, and there are freezing dead corners in the refrigerator. The degree of freezing of the food is different, and the cooling effect is poor.
4. The humidity of the air is high, which is easy to cause the food in the freezer to stick together and freeze together, and it is not easy to separate; the food in the refrigerator will have the problem of wetness, which affects the appearance and taste of the food.

Advantages of air cooling:

1. The air-cooled refrigerator basically does not form frost on the inner wall of the refrigerator, which avoids the trouble of manual defrosting by users, and saves the user's worry and effort, so it is welcomed by many consumers.
2. The cooling air is forced to circulate by the fan, the cooling speed of the refrigerator is faster, and the distribution of the cold air is more balanced.
3. The temperature of the air-cooled refrigerator is uniform, and the temperature of the thermostat is almost the same as the temperature of other places in the refrigerator, so the temperature control is more accurate.
4. The evaporator and the food are separated and the fan forced the air flow, so that the humidity inside the refrigerator is lower, and the food will not freeze together, and it will not appear wet. The circulating cold air flow also makes the refrigerator smell relatively fresh.

Disadvantages of air cooling:

1. The complex structure of the air-cooled refrigerator causes a relatively high failure rate, and the cost also rises, and the price is higher than that of the direct-cooled refrigerator.
2. In order to realize the circulation of cold air, the fan has a large workload, and at the same time, the automatic defrosting will also increase the energy consumption, so the power consumption is large, and there is no direct cooling energy saving and environmental protection.
3. The frequent flow of air-conditioning and larger customs result in faster evaporation of water, and food moisture is easy to lose. If you do not take insurance methods similar to airtight fresh-keeping boxes, fruits and vegetables and other foods are easily dehydrated and dried.