The maintenance and maintenance of an ultra-low temperature refrigerator are very important for normal usage and prolonging its life. If the inaccurate temperature control often results in the damage of the protected objects, which will greatly affect the experimental results, thus affecting the normal progress of the research work.

1. Clean it once a month to ensure its cleanliness
Remove the dust on the inside and outside of the refrigerator and accessories by a dry cloth. If the refrigerator is too dirty, use a neutral detergent and rinse thoroughly after cleaning. But remember not to flush the upper and inside of the refrigerator, otherwise, the insulating material will get damaged and fail later. Lubricants are not necessary for compressors and other mechanical parts. The cleaning of an electric fan in the rear of the clean compressor must be careful. After the cleaning, make a safety check to ensure that the plug of the fridge is inserted and not virtual connected. There is no abnormal heat in the plug, as well as the power cord and distribution wire on the back of the refrigerator, are not broken and nicked.

2. The cooling of the refrigerator is not sufficient
Check whether there is ice on the surface of the evaporator; whether or not the door of the refrigerator is over – frequency; whether the back of the refrigerator is in contact with the wall; whether or not there is too much stuff on.

3. The refrigerator is too noisy
Check whether the baseboard and the refrigerator are stable if not, adjust the movable screws to make the four corners firmly support on the floor. And make sure whether the back of the refrigerator is touched by something.