Cold storage refrigeration problems, knowledgeable progress.

1. (1) The cold storage has poor sealing or heat insulation performance, and the cold storage or refrigerator has poor sealing or heat insulation performance, which causes the cold energy obtained by the refrigeration device to escape. This phenomenon is called "escape from cold" or cold consumption. The insulation thickness of equipment, pipelines, insulation walls, etc. is not enough, and the insulation effect is not good, or the gas-proof layer of insulation structure is destroyed, which makes the insulation material damp and will rot after a long time of damp. Whether it is damp or rotten, the thermal insulation performance of materials will be significantly reduced and the cooling capacity will be significantly increased, especially for low-temperature equipment. In addition, the evaporator water tank cover is not tight, the sealing strip of air treatment room or refrigerator door is not tight, and the air conditioning pipeline and room doors and windows leak.

Whether the sealing strip of the refrigerator door is tight, just close the door and check the size of the gap between the sealing strip (also called rubber band) and the door frame. Generally, try inserting the cardboard with a thickness of .2-.3mm and a width of 2-3mm. If the cardboard is inserted, it means that the gap is punched. Where there is a big gap, we should try to repair it, otherwise, the cold loss will be serious, which will make the temperature of the library unable to drop. If there is dew condensation around the door (sweating) or somewhere on the insulation wall of the cold storage, this is a serious manifestation of "escape from the cold" and should be repaired in time.

It is difficult to maintain the integrity of the gas barrier when repairing due to the troublesome work of replacing the moisturizing material. Therefore, we must pay attention to the construction quality of the heat insulation layer in the cold storage project.

(2) The frost layer is too thick. For the cold storage with the storage temperature below ℃, the water vapor in the air will frost when it touches the evaporator surface. It is better to have a thin frost layer on the evaporator. If the frost layer is very thick or even like a popsicle, the heat transfer performance of the evaporator will be greatly reduced, resulting in a decrease in refrigeration capacity and a cold storage temperature. In this case, defrosting should be done in time.

in the system with defrosting device, defrosting shall be carried out according to the defrosting operation requirements. If there is no defrosting device, you can stop the machine, open the warehouse door, let the temperature rise and defrost by yourself, or use tap water to defrost, but when defrosting, you should move the frozen things out of the warehouse. After defrosting or flushing, the frost and water in the warehouse should be cleaned. In the process of defrosting or defrosting, it is not allowed to beat the evaporator with wooden sticks or iron to avoid damage to the evaporator.

(3) the expansion valve flow is too large or too small. The flow rate of expansion valve is adapted to the refrigeration capacity at evaporation temperature required by refrigeration equipment. Generally speaking, when the refrigeration equipment is installed and debugged, the flow rate of the expansion valve has been adjusted to the evaporation temperature range required by the refrigeration system according to the specified suction superheat. In normal operation, the heat will be automatically adjusted according to the heat load. If the working condition of the refrigeration system changes due to some reasons of the system, such as the decrease of the compressor displacement, the high condensation temperature, the change of the amount of refrigerant injected into the system (added during maintenance), etc., the flow of the expansion valve will exceed the automatic adjustment range. At this time, it is necessary to readjust manually.

if the evaporator pressure is too high, but it can't be lowered, it means that if the evaporation temperature is high, the temperature in the freezer can't be lowered. To reduce the evaporator temperature, only readjust the expansion valve. But it can't be adjusted too low. If it is too low, the refrigeration capacity of the freezing room will be insufficient, and the temperature of the freezing room will not drop. At this time, the expansion valve should be readjusted.

the flow rate of the expansion valve can be judged by observing the frosting change of the suction pipe according to the evaporation pressure change reflected by the suction pressure gauge. The evaporation pressure is too high, and the frost reaches the suction stop valve again, indicating that the flow rate of the expansion valve is too large. On the other hand, if the evaporation pressure is too low and the frost does not reach the suction pipe, it means that the expansion valve flow is too small. However, it should be noted that judging the level of evaporation pressure is correct only when the refrigeration equipment runs continuously for a long time (at least over 1 hour), its evaporation pressure does not change or changes very little, and the heat load in the freezer does not change much.

2.

1. No matter what type of refrigerator is installed, the refrigerator should be placed in a cool and ventilated place, and a gap should be left between its back and the wall, which can save energy by about 2% every day compared with sticking to the wall.

2. The refrigerator should be opened less frequently and quickly. In addition, the temperature adjustment gear in the refrigerator should be moderate, and it is not suitable to place strong cold, so as to avoid increasing the workload and power consumption of the refrigeration cycle system in the refrigerator.

3. The general food preservation effect is the best at 8-1℃. Store food should not be too full, and there should be a gap of more than 1 mm between the food and the box to facilitate the convection of cold air in the box.

4. When storing hot food, put it in the refrigerator after it is cold, and store it in small pieces to avoid repeated freezing. Chicken, fish, etc. are eviscerated, refrigerated first and then frozen, thus reducing electricity consumption.

5. Generally, when the frost layer on the surface of the evaporator in the refrigerator reaches more than 5 mm, it should be defrosted. If the frost is too thick, it will produce great thermal resistance and increase power consumption. Always keep the back of refrigerator clean, because the dust on the surface of condenser and compressor will affect the heat dissipation effect.

6. In summer, there are generally few things in the freezer. At this time, several containers such as plastic boxes or microwave oven boxes can be filled with water and put into the freezer. After the water becomes ice cubes, the ice cubes will be transferred to the freezer and placed under or next to the thermostat, so that when the cold air is emitted upwards, the temperature around the thermostat will be reduced, thus reducing the number of times the thermostat is started and achieving the purpose of saving electricity. At the same time, when the ice melts, it will absorb a lot of heat, which will also play a role in cooling and keeping fresh the food stored in the refrigerated room.

2.1. No matter what type of refrigerator is installed, the refrigerator should be placed in a cool and ventilated place, and a gap should be left between its back and the wall. How can it be maintained every day compared with sticking to the wall?

3.1. After the cold storage is newly installed or stopped for a long time, it should be used again, and the cooling speed should be reasonable: it should be controlled at 8-1℃ every day, and it should be kept at ℃ for a period of time.

2. protection of the library board: pay attention to the collision and scratching of hard objects on the library body during use, otherwise it will cause depression and corrosion of the library board, which will seriously reduce the local thermal insulation performance of the library body.

3. Sealing protection: As the assembled cold storage is made up of several insulation boards, there are certain gaps between the boards. During construction, these gaps will be sealed with sealant to prevent air and moisture from entering, and some parts with sealing failure should be repaired in time.

4. Ground protection: Generally, the ground of small assembled cold storage uses insulation board. When ls-14gls uses cold storage, it should prevent a large amount of ice and water from being stored on the ground. If there is ice, it must not be knocked by hard objects to damage the ground.

4. If it's a low-temperature warehouse, it can do many kinds of business

such as fresh food, ice cream, seafood, dry goods, etc.

It's a bit confusing, so please forgive me. Please adopt it if you feel good?