Many laboratories use ultra-low-temperature refrigerators to ensure the safety of valuable samples. There are many types of the ULT refrigerator, which can operate between – 86 °C and – 45 °C and the internal temperature of the refrigerator is maintained between – 70 ° C and – 80 ° C.
What Is the Ultra-low Temperature Refrigerator?
Ultra-low temperature refrigerator, also known as ultra-low temperature freezer, is widely used as a laboratory refrigerator, to store drugs, vaccines, enzymes, hormones, stem cells, platelets, and samples extracted from the human body, plant seed germplasm bank, gene cloning bank, and some important biological and chemical reagents. The most common type is a –86 °C ultra-low temperature refrigerator, and there are also ultra-low temperature refrigerators of – 120°C, – 135°C, – 160 °C and – 192°C.
Features
Unique refrigeration mode, about 30% higher efficiency than traditional mode.
Environmentally friendly fluorine-free refrigerant is used for refrigeration.
Silent design, extremely low noise, creating a quiet office space.
Unique condensation mode which is half natural convection and half air cooling. Even if the air condenser is dirty and blocked, it is not easy to cause damage to the compressor.
Most ultra-low temperature refrigerators adopt an overlapping compressor system, that is, one of the compressors then reduces the temperature to ultra-low temperatures, such as – 86 °C. The other type of double-safety refrigerator is to adopt two sets of completely independent compressors for refrigeration.
Working Process
When the panel displays that the temperature is higher than the set temperature when the power is turned on, the first-stage compressor starts first, which makes the condenser temperature of the second-stage refrigeration system drop. After a few minutes of delay, the second stage refrigeration system also starts to work and the evaporator is on the inner wall of the refrigerator, which can make the internal temperature of the refrigerator drop a lot. The heat released by the condenser is absorbed by the evaporator of the first-stage refrigeration system and The heat released by the first-stage condenser is dispersed into the air.
When the internal temperature of the refrigerator reaches the set temperature, the resistance of the temperature-sensing probe transmits the information, and the control relay loses power and is disconnected. The two-stage refrigeration system stops working. When the temperature in the ultra-low temperature refrigerator rises again and exceeds the set temperature, the ultra-low temperature refrigerator repeats the above operation process again, so that the temperature in the refrigerator is always around the set temperature.
Where to Put the Ultra-low Temperature Refrigerator?
No matter where you put the ultra-low temperature refrigerator, the local temperature should be lower than 32 ° C, otherwise, it is too hot for the refrigerator. In addition, if you plan to place several ultra-low temperature refrigerators in a room, the ultra-low temperature refrigerator will need ventilation space. The recommended ventilation clearance is 203 mm above the ULT refrigerators and 127 mm at the back. If the place of placing the ULT refrigerators cannot meet the environmental requirements of the laboratory, the water-cooled condensers can be added to prevent them from overheating.
In addition to considering the local environmental factors of the refrigerator, the size of the refrigerator itself also should be considered. In addition to finding a space large enough and suitable enough, the refrigerator passing through all the doors of the laboratory should be ensured.
How to Prolong the Service Life of the Ultra-low Temperature Refrigerator?
First of all, you need to ensure that any researcher can use the ultra-low temperature refrigerator correctly, instead of using it as a quick-freezing machine. In addition, you need to ensure that researchers know that warm samples should not be put into the freezer. Although the ULT freezer can hold some unfrozen samples, if you abuse the ULT refrigerator, the compressor may be damaged within a few years. Finally, there are some maintenance procedures to help keep the refrigerator clean and dust-free. Taking some precautions for the ultra-low temperature refrigerator, such as cleaning the condenser filter and coil, cleaning the door gasket, properly storing materials, defrosting, paying attention to the freezing alarm, replacing the backup battery every 2.5 years, removing any frost, monitoring the vacuum relief port.
