Reasons why the high and low temperature test chamber cannot keep low temperature

Refrigeration failure analysis of high and low temperature test box that cannot be kept at low temperature. First observe whether the high and low temperature box refrigeration compressor can be started during the high and low temperature test box operation. If the high and low temperature compressor can be started during the operation, it means that from The electrical lines from the main power supply to each high and low temperature box compressor are normal, and there is no problem in the electrical system.

When there is no problem with the electrical system of the high and low temperature box, continue to check the refrigeration system. First, check the two sets of high and low temperature refrigeration compressors. If the exhaust and suction pressure of the low temperature compressor are lower than normal, and the suction The air pressure is evacuated, which indicates that the main refrigerant is obviously insufficient. Touch it again by hand. The exhaust and suction lines of the main unit of the high and low temperature box R23 compressor. If the temperature of the exhaust line is not high, the temperature of the suction line is not low. This also shows that the host The lack of refrigerant in group R23.

The high and low temperature test box is a main unit, and the other is an auxiliary unit. When the cooling rate is large, the two units work at the same time. At the initial stage of the temperature maintenance price, the two units are still working at the same time. The unit stops working, so there is no temperature stabilization phenomenon, and the cooling rate is indicated to decrease. During the temperature maintenance phase, once the auxiliary unit stops working, the main unit has no cooling effect, and the air temperature in the high and low temperature test box will slowly rise. When the temperature rises to a certain level, the control system will start the auxiliary unit to cool down, and then the auxiliary unit will stop working again. If this is repeated, the failure phenomenon of low temperature cannot be maintained.