1) The refrigeration compressor unit is not installed for vibration reduction, or the vibration reduction effect is not good. According to the installation specification, the overall vibration reduction device of the unit should be installed. If the vibration reduction is not standardized or there is no vibration reduction measure, the machine will vibrate violently, which will easily cause the pipeline to crack, the equipment to vibrate, and even the machine room to vibrate.
2) There is no or lack of oil return bend in the refrigerant pipeline. When the pipeline for conveying refrigerant is turned from horizontal to upward, it must be made into a small bend that first hangs down and then goes up, that is, a U-shaped bend, so that the pipeline can be qualified when it goes up, and it cannot be directly made into a 90-degree turn to go up. Otherwise, the oil in the system will not be able to return to the compressor well, and a large amount of oil will be deposited in the cooling fan, which will make the fan and the entire system unable to function normally, and even damage the fan and unit equipment.
3) The refrigerant pipeline connection is not balanced. When the unit pipeline is connected to a group of multiple compressors, in order to evenly distribute the oil return to each compressor, the main pipeline interface must be set in the middle of the multiple heads, and then some branch pipes should be set on both sides. so that the return oil flows into multiple compressor branch pipes evenly.
Moreover, each branch pipe should be equipped with valves to adjust the oil return. If this is not the case, but multiple downward branch pipes are drawn from different parts of the main pipeline and connected to multiple compressors, the oil return will be uneven, and the first oil return is always the most full, and the latter one in turn. Gradually reduce the oil return. In this way, the first compressor may malfunction, the vibration is huge, the oil pressure is too high, and the unit is overheated, resulting in accidents such as compressor flushing/locking, and damage to the equipment.
4) The pipeline is not insulated. If there is no insulation material, the cold pipeline will be frosted at the ambient temperature, which will affect the cooling effect, increase the load of the unit, and then make the unit run over-strength and reduce the service life of the unit.
5), to regularly check the technical indicators, timely adjustment. The operating temperature and pressure of the system, as well as the amount of lubricating oil and refrigerant, should be checked and adjusted in time. The system should have automatic control and compressor alarm devices. Once there is a problem, an alarm prompt will be issued, or an automatic protective shutdown will occur, and the compressor will be shut down.
6), maintenance of the unit. To regularly change the lubricating oil, filter. Refill refrigerant as needed. The condenser should be cleaned and kept clean at any time, so as to avoid dust, sediment or flying debris, which will affect the cooling effect.
Some people think that as long as the lubricating oil is free of impurities, it can continue to be used, although it has been used for more than two years, it does not need to be replaced. This is clearly wrong. If the lubricating oil runs at high temperature in the system for a long time, its performance may have changed, and it cannot play the role of lubrication. If it is not replaced, it will increase the operating temperature of the machine and even damage the machine.
Filters should also be changed regularly. We know that general machines have “three filters”, which must be replaced regularly. The refrigeration compressor system may not have “three filters”, but only one oil filter, which should also be replaced regularly. The idea that the filter is metal and doesn’t have to be replaced if it isn’t damaged is unfounded and untenable.
7), the installation environment and maintenance of the air cooler. The location and environment of the air cooler inside the cold storage will affect its operation. Generally, the air cooler near the cold storage door is prone to condensation and frost. Since its environment is located at the door, the hot air outside the door enters when the door is opened, and condensation, frost, or even freezing occurs when it encounters the air cooler. Although the cooling fan can automatically heat and defrost regularly, if the door is opened too frequently, the opening time is too long, and the time and quantity of hot air entering are long, the defrosting effect of the fan is not good. Because the defrosting time of the air cooler cannot be too long, otherwise the cooling time will be relatively shortened, the cooling effect will not be good, and the storage temperature cannot be guaranteed. Article source Refrigeration Encyclopedia
In some cold storages, due to too many doors, the opening frequency is too high, the time is too long, the door has no insulation measures, and there is no partition wall inside the door, so that the cold and hot air flow inside and outside are directly exchanged, and the air cooler near the door will inevitably encounter serious damage. frost problem
8) Drainage of the melted water when the air cooler defrosts. This problem is related to how severe the frosting is. Due to the serious frosting of the fan, a large amount of condensed water will inevitably be generated. The fan water receiving tray cannot withstand it, and the drainage is not smooth, so it will leak down and flow to the ground in the warehouse. If there are stored goods below, the goods will be soaked. In this case, a drain pan can be installed, and a thicker guide pipe can be installed to remove condensed water.
Some air coolers have the problem that water is blown from the fan and sprayed onto the inventory in the warehouse. This is also the problem of fan frosting in a hot and cold exchange environment. It is mainly the condensed water generated by the fan page in a hot environment, not the problem of the defrosting effect of the fan itself. To solve the fan condensate problem, the environment must be improved. If there is a partition wall in the warehouse door in design, the partition wall cannot be cancelled. If the partition wall is cancelled in order to facilitate the entry and exit of goods, the environment of the fan will be changed, the cooling effect will not be achieved, the defrosting effect will not be good, and even frequent fan failures and equipment problems.
9) The problem of the condenser fan motor and the electric heating pipe of the air cooler. This is a wearing part. Fan motors that run for a long time in a high temperature environment may malfunction and be damaged. If it is very important to ensure the temperature of the cold storage, some vulnerable parts should be ordered for timely maintenance. The electric heating tube of the air cooler also needs to have spare parts to be more secure.
10), the problem of cold storage temperature and cold storage door. A cold warehouse, how big is the area, how much inventory, how many doors are opened, the time and frequency of door opening and closing, the frequency of inventory in and out, and the throughput of goods are all factors that affect the temperature in the warehouse.
11) Fire safety issues in cold storage. The cold storage is generally around minus 20 degrees. Due to the low ambient temperature, it is not suitable to install a fire sprinkler system. Therefore, more attention should be paid to fire prevention in the cold storage. Although the ambient temperature of the cold storage is low, if a fire occurs, there are combustibles in the storage, especially the inventory is often packed in cartons and wooden boxes, which are easy to burn. Therefore, the risk of fire in the cold storage is also very large, and fireworks must be strictly prohibited in the cold storage. At the same time, the air cooler and its wire box, power cord, and electric heating tube should also be checked frequently to eliminate electrical fire hazards.
12) The ambient temperature of the condenser. The condenser is generally installed on the roof of the outdoor building. In the environment with high temperature in summer, the temperature of the condenser itself is very high, which increases the operating pressure of the unit. If there is a lot of high temperature weather, you can build a pergola on the roof to block the sunlight and reduce the temperature of the condenser, so as to reduce the pressure of the machine, protect the unit equipment, and ensure the temperature of the cold storage. Of course, if the capacity of the unit is sufficient to ensure the storage temperature, it is not necessary to build a pergola.
Post time: Nov-28-2022
