Solution to Thermal Shock Test chamber Refrigeration System Blocking

Solution to Thermal Shock Test chamber Refrigeration System Blocking 

Thermal shock test chamber is generally composed of compressor, air conditioning evaporator, cooler and pipe system software. Refrigeration system blockage generally has two kinds of dirty blockage and ice blockage, and oil blockage is relatively rare.

1. Dirty and blocked

When the compressor of thermal shock test chamber is damaged, and there is waste in the refrigeration system, this waste is very easy to block in the capillary or filter device, which is called dirty plugging. Dirty blockage is because there is residue in the refrigeration system (oxygenated skin, copper chips, welding through), when it is circulated with the refrigerant system, it causes blockage at the capillary or filter device.

Dirty blockage removal method: remove the capillary tube, filter device, cooler, air conditioning evaporator with gas cutting, disassemble the carbon molecular sieve in the capillary tube and filter device, clean the cooler and air conditioning evaporator, carry out dry, vacuum packaging, welding, and fill with refrigerant.

2. Ice jam

Ice blockage is caused by water entering the refrigeration system of thermal shock test chamber. Due to its own with a certain amount of moisture, coupled with the maintenance or refrigerant in the whole process of taking time processing regulations are not tight, so that water and gas into the system software. Under the ultra-high pressure effect of the compressor, the refrigerant is changed from a liquid to a vapor state, so that the water is passed into the narrow and long capillary tubes with the refrigerant circulation system. When the moisture content of each kilogram of refrigerant exceeds 20mg, the filter device is saturated with water, and the water can not be filtered out. When the temperature of the capillary inlet and outlet is 0 ° C, the water is converted from the refrigerant and becomes ice, resulting in ice blocking.

Dirty blocking and ice blocking are divided into full and half blocked, the common fault condition is that the air conditioning evaporator is not frosting or frosting is not full, the temperature behind the cooler is high, and the hand drying filter or capillary entrance feels that the temperature is basically the same as the indoor temperature, sometimes less than the indoor temperature, and a lot of steam is sprayed out of the cutting process pipe. After the ice jam occurs, the friction resistance of the compressor exhaust pipe increases, resulting in the compressor overtemperature, the overload protector is working, and the compressor stops running. After about 25 minutes, a part of the ice jam melts, the compressor temperature decreases, the contact point of the temperature controller and the overload protector is closed, and the compressor starts the refrigerator. Therefore, the ice blockage has regularity, and the air conditioning evaporator can see regular frosting and defrosting conditions.