Commercial Freezer Room is very the efficient storage facility for frozen products such as frozen meat, frozen seafood, etc. Foods can be kept for a long time with the help of commercial freezer room, it is very helpful for fresh food business development. Some customers want to cool down the temperature of commercial freezer room quickly within a regular time. But it needs time, let me list some reasons for that.
1. PU sandwich panels of commercial freezer room don’t work well
Firstly the thickness of PU sandwich panel for the commercial freezer room is not thin enough, so the insulation effect is poor. Secondly the density of PU sandwich panel is not enough. If frost occurs in the seal of commercial freezer room door, it means that seal is not tight. In addition, frequent switching of commercial freezer room doors or more people come into and go out from the commercial freezer room will also increase the cooling consumption, so let’s try to avoid opening the door frequently. If large quantity products are loaded into the commercial freezer room, the thermal load increases sharply. The commercial freezer room needs to take a long time to cool down to the specified temperature.
2. The frost of the evaporator is serious, or dusty is excessive, the heat transfer effect will reduce.
Because the evaporator temperature of commercial freezer room is lower than 0℃, and the humidity of commercial freezer room is high, the moisture in the air is easily frosted on the surface of the evaporator, which affects the heat transfer effect . To prevent more thicker frost on the fin surface of evaporator, we need to set defrost time periodically.
3.There is much air or frozen oil in the evaporator, the heat transfer effect will reduce.
Once inner surface of the evaporator heat transfer tube is attached with much frozen oil, the heat transfer coefficient will be reduced. Similarly, if there is much air in the heat transfer tube, heat exchange area and heat transfer is reduced, so commercial freezer room temperature will cool down slowly. Therefore, in daily operation and maintenance, we should remove the oil and exhaust the air in the evaporator in time to improve the heat transfer efficiency of the evaporator.
4. The throttle valve is improperly adjusted or blocked, the refrigerant flowing rate is too large or too small.
If the opening degree of the throttle valve is too large, flowing rate of the refrigerant will be too large, the evaporation pressure and evaporation temperature will increase, so commercial freezer room temperature will cool down slowly; Meanwhile, if the throttle valve opening degree is too small or blocked, flowing rate of the refrigerant will be reduced, the cooling capacity will be reduced, so commercial freezer room temperature will cool down slowly. Generally, we could judge whether the flowing rate of the throttle valve refrigerant is appropriate by observing the evaporation pressure, the evaporation temperature, and the frosting condition of the suction pipe. Blockage of the throttle valve is an important factor affecting the flowing rate of the refrigerant. The main reasons for the blockage of the throttle valve are ice blockage and dirty blockage. Ice blockage is due to the poor drying effect of the dry filter, refrigerant contains moisture, when it flows through the throttle valve, it drops negative temperature, the moisture in the refrigerant becomes to be ice and blocks the throttle hole; Dirty blockage is due to the accumulation of more dirt on the filter inlet of the throttle valve, so the refrigerant flows poorly, it caused dirty blockage.
5. Refrigerant is not enough in the system, cooling capacity is poor.
There are two main reasons for the insufficient refrigerant circulation. Firstly, the refrigerant charge is not enough, in this case, we just fill in sufficient refrigerant in system. Secondly, the refrigerant leaks seriously in the system, in case of this situation, we need to find the leakage point and seal it soon.
6. Low efficiency of compressor, the cooling capacity can’t meet the commercial freezer room load requirements
Due to the long-term operation of the compressor, the components such as the cylinder liner and the piston ring are severely worn, the gap is increased, the sealing performance is reduced accordingly, the gas transmission coefficient of the compressor is also reduced, so the cooling capacity is reduced. When the cooling capacity is less than the heat load of cool room, temperature will cool down slowly. We could observe the suction and exhaust pressure of the compressor to judge refrigeration capacity of the compressor. If the refrigeration capacity of the compressor drops down, the common method is that replacing the cylinder liner and piston ring of the compressor, If it can’t be effective after replacement, we need to disassemble and repair it.
