Management and Use of Cold Storage and Analysis and Troubleshooting of Common Faults

2025-04-30

The management of the warehouse should establish a special team. Special attention should be paid to preventing water ingress, moisture, heat, cold loss, and refrigerant leakage. It is necessary to strictly control the five aspects of ice, frost, water, doors, and lights.

Ice, frost, and water on the walls, floors, doors, ceilings, and other parts of the corridor and the warehouse should be removed in a timely manner.
The air coolers in the warehouse should be defrosted and deiced in a timely manner to improve the refrigeration efficiency and save electricity. There should be no accumulated water in the water trays of the air coolers.
Hot goods that have not been frozen should not be put into the frozen goods storage room to prevent damage to the cold storage and ensure the quality of the goods.
The cold storage doors should be well managed. Close the doors promptly when goods are brought in or out. If the doors are damaged, repair them in a timely manner to ensure that they can be opened flexibly and closed tightly without cold leakage.
01 Warehouse Management
In order to protect the floor and prevent it from being damaged by freezing and swelling, goods should not be directly laid on the floor for freezing. Hooks or trays should not be dropped or struck on the floor, and stacking and piling should not be reversed or disassembled.
The weight of the stacked goods and the suspended goods on the overhead rails should not exceed the designed load.
In the chilled goods storage room without floor anti-freezing measures, the floor should be prevented from freezing and swelling during use.
A comprehensive inspection of the building's usage should be carried out regularly. If any problems are found, they should be repaired in a timely manner. The electrical lines in the warehouse should be regularly maintained to prevent electric leakage, and turn off the lights when leaving the warehouse.
02 Goods Storage and Hygiene
The cold storage should strengthen the management of goods storage and hygiene, attach importance to goods maintenance, strictly implement the "Food Hygiene Law", ensure the quality of goods, and reduce the loss of dry shrinkage. A full-time quality inspector (warehouseman) should be assigned to be responsible for inspecting the quality of goods entering and leaving the warehouse. The warehouse should meet the requirements of food hygiene.
The storage quality guarantee period of the goods in the warehouse should be strictly controlled. Regular inspections should be carried out, and the principle of "first in, first out" should be followed. If any abnormal changes in the goods are found, a quality inspection form should be issued in a timely manner, and the problem should be dealt with promptly together with the consignor.
The following goods should be selected, sorted out, or repackaged before being put into storage. The following goods should not be put into storage:
Spoiled, rotten, or goods with peculiar smells and those that do not meet the hygiene requirements;
Fresh eggs that have been exposed to rain or soaked in water;
Goods that have been pickled with salt or soaked in brine (except for warehouses and special warehouses that have been antiseptic-treated), goods without tight packaging, and goods with flowing juice or water;
Flammable, explosive, toxic, and chemically corrosive goods.
03 Common Problems and Failures of Cold Storage Equipment
Regularly check and confirm whether the voltage of the power supply meets the requirements. The voltage should be 380V±10% (three-phase four-wire). When the cold storage equipment is not used for a long time, the main power supply of the cold storage should be cut off, and it should be ensured that the refrigeration unit is not affected by moisture or contaminated by dust and other substances.
The condenser on the refrigeration unit is easily contaminated and should be cleaned regularly according to the actual situation to maintain good heat transfer efficiency. Good heat dissipation ensures good refrigeration. Do not stack sundries around the refrigeration unit.
The electrical equipment in the cold storage should be protected from moisture to prevent electric shock accidents caused by electric leakage.
The hinges, handles, and door locks of the cold storage doors should be lubricated regularly according to the actual situation.
The maintenance of the electrical equipment in the cold storage should be operated by an electrician or a person with electrical knowledge. Any maintenance must be carried out after cutting off the power supply to ensure safety.
During the operation of the refrigerator, vibration should be avoided. In addition to increasing mechanical wear, vibration may also cause the connecting pipes on the unit to loosen or break. If abnormal noise is found during the operation of the machine, it should be stopped for inspection, and it can be restarted after the problem is eliminated. The protection functions of the refrigeration compressor unit have been preset and do not need to be adjusted.
Regularly check whether the connecting pipes of the refrigeration unit and the connecting pipes on the valves are firm and whether there is refrigerant leakage (usually, there will be oil stains at the leakage points). The most practical method for leak detection is to dip a sponge or a soft cloth in a detergent, rub it to form foam, and then evenly apply it to the place to be leak-detected and observe for a few minutes. If there is a leak, bubbles will appear. Mark the leaking place and then carry out fastening or oxyacetylene welding treatment (maintenance operation should be carried out by professional refrigeration workers).
Sundries should not be stacked on the top (ceiling panel) of the cold storage. Otherwise, the storage panels of the cold storage will be deformed, affecting the thermal insulation performance. Keep the passages around the cold storage unobstructed. Only by ensuring good heat dissipation can good refrigeration be achieved. The location where the cold storage is placed should be kept dry, clean, free of flammable and explosive items, and ensure that there are no safety hazards. Do not stack items in front of the evaporator (leave a certain gap) to avoid affecting the refrigeration effect.
If the humidity of the air is too high, the defrosting interval is too long, or the temperature setting in the warehouse is abnormal, all these will lead to the thickening of the frost layer on the evaporator in the warehouse and the failure of the warehouse temperature to drop. At this time, defrosting treatment should be carried out. Observe in a timely manner and stop defrosting immediately when the frost layer disappears. Wait for a while and then start the equipment.
Parameters such as the temperature and temperature difference in the cold storage should be set according to the actual situation of the cold storage, and the parameters should not be changed arbitrarily. The cold storage has been customized according to the user's requirements when it leaves the factory. Set the parameters on the controller after understanding the technical parameters of the cold storage.
The compressor should avoid frequent starting, and the interval between each shutdown should not be less than 6 minutes. When it is found that the oil level in the oil sight glass of the compressor drops or becomes dirty, it is necessary to add or replace the oil in a timely manner. Do not add unqualified refrigeration oil with the wrong brand or that has been exposed to the air for a long time and has a high water content, otherwise, it will cause failures such as high-temperature carbonization, low-temperature wax precipitation, damage to the motor insulation, and difficulties in oil return of the system. Always pay attention to the temperature changes on the compressor housing, the body, and the cylinder head to determine whether the compressor is operating normally.
The refrigeration compressor unit generally does not need to be refueled. If refueling is determined to be necessary, professional personnel should add the special oil for the compressor, and the amount of oil added should be determined by professional personnel. Do not add oil blindly.
Regularly check whether the power supply voltage is normal (three-phase four-wire) and whether the protection function of the main power switch is normal and effective.
04 Common Failures and Troubleshooting
There is no power on the distribution box or the display screen does not display. Please check whether the special switch of the cold storage is out of order. (Check on the power supply and the distribution box)
The cold storage does not refrigerate or has poor refrigeration effect. Check whether the condenser of the refrigerator is dirty. Check whether the frost on the evaporator in the warehouse is too thick. Check whether there is refrigerant leakage (apply soapy water to the pipeline joints, and the generation of bubbles indicates refrigerant leakage). And ask professional personnel to replenish the refrigerant and deal with the leakage.
Check whether the seal of the cold storage door is intact and eliminate the problem. Check whether the refrigerator of the cold storage is working. Check whether the parameter settings of the computer controller of the cold storage are correct and readjust them. Check whether the controller of the cold storage is out of order and replace it. Check whether there is enough clearance for the stacked items in the warehouse and clear it.
There is abnormal noise during the operation of the machine. Please stop the machine for inspection to see if it is caused by vibration or mechanical failure. There is abnormal noise in the distribution box, which is the sound emitted by the AC contactor. This is due to reasons such as the damage of the contactor, the inflexibility of the moving parts of the electromagnet, and the presence of dirt on the suction surface of the electromagnet. Please cut off the power supply, press the electromagnet of the contactor back and forth or remove the contactor for cleaning to eliminate the noise.
The refrigerator starts frequently, does not start for a long time, does not stop after running for a long time, or stops before the warehouse temperature reaches the set value.
Check whether there is dirt on the condenser. Poor heat dissipation will lead to the excessive condensation pressure of the refrigerator. To protect the compressor, the machine stops running under the action of the pressure controller. After good heat dissipation, press the black reset button on the pressure controller, and the machine can automatically resume operation.
The parameter settings of the controller are incorrect.
Just reset them.
If the refrigeration is not good, please refer to failure 2.
The temperature control is out of order.
The electrical equipment is damaged.
After closing the switch, the distribution box of the cold storage does not respond, but the three-phase power is normal. Please check the neutral wire to see if there is a voltage of 220V. The components (various valves, controllers) of the cold storage have all been set, and there are no parts that need to be adjusted by the user.
The lights in the warehouse do not light up. Please check whether the switch is out of order and whether the bulb is damaged. Cut off the power supply during the inspection, and pay attention to the waterproofing of the lights when installing the lampshade.
When the ambient temperature is too high, after the refrigerator runs for a period of time, the warehouse temperature has not reached the set value but the refrigerator stops in advance.
This is because the ambient temperature rises, resulting in the excessive condensation pressure of the refrigerator. To protect the compressor, the machine stops running under the action of the pressure controller. After good heat dissipation, press the black reset button on the pressure controller, and the machine can automatically resume operation. And check whether the water condenser has good heat dissipation. Do not adjust the set value on the pressure controller arbitrarily, otherwise, the pressure controller will not be able to protect the refrigerator.
The cold storage door does not close tightly. Please adjust the distance between the hinge and the door lock of the storage door and the storage body. (The adjustment range should not be too large, otherwise, the opening and closing of the storage door will be very inflexible.)
Analysis and Troubleshooting of Common Failures