Maintenance method of high and low temperature test chamber without cooling

There are six main reasons why the high and low temperature test chamber does not cool down Please check and repair one by one I judge whether there is voltage supply to the compressor 1 Whether the AC contactor connected to the compressor unit is closed? 2 Whether the wire connected to the compressor is broken or not well connected? 3 Judge whether the voltage meets the rated voltage requirements of the compressor II Judge the current of the compressor unit The current must reach the rated current of the compressor If the voltage is normal and the current does not meet the requirements, it means that there is no refrigerant (refrigerant) III If the high and low temperature test chamber is a cascade unit, observe whether both units are in operation If one unit is not in operation, shut down immediately for inspection Find out the cause of the compressor that does not work and analyze and solve it IV observe whether the cooling fan of the condenser is working? When it is working, is the direction of the cooling fan normal? When it is working normally, the wind direction should blow outward V judge whether the compressor is short of refrigerant, and use the pressure gauge to observe whether the pressure of the compressor after starting the current equipment is normal? Or touch the temperature of the high-pressure exhaust pipe of the compressor by hand Normally, it should be very hot If double unit refrigeration, it is necessary to determine which compressor is short of refrigerant Vi observe whether the indoor circulating fan works normally If it is burnt out and does not work, the evaporator cannot evaporate normally, so that it cannot cool down.