The main reasons for the freezing and cracking of copper tubes in central air-conditioning chiller unit:
1. Operational errors and failure of the pressure control system: Operator errors may lead to improper system parameter settings, such as the evaporation pressure drops too low and is not adjusted in time or the pressure controller fails to automatically shut down when the pressure is abnormal, which will cause the temperature in the evaporator to be too low, which may cause the chilled water to freeze, causing physical damage to the copper tube and eventually leading to freezing and cracking.
2. Copper tube material or manufacturing defects: If there are quality problems with the evaporator copper tube itself, such as insufficient material purity, manufacturing process defects, etc., these may reduce the pressure bearing capacity and corrosion resistance of the copper tube, causing the copper tube to gradually weaken in long-term operation, and eventually rupture due to inability to withstand normal working pressure or slight frost heave stress.
3. Low evaporation pressure and over cooling: When the evaporation pressure of the evaporator is too low, it means that the evaporation temperature is far lower than the design value, which will cause the chilled water to over cool or even freeze. The volume of ice is larger than that of water, which will form an expansion force inside the copper tube, directly acting on the copper tube wall, causing physical damage, and in severe cases, it will cause the copper tube to freeze and crack.
4. Inadequate maintenance and failure of protection mechanisms: Regular maintenance is essential to ensure the normal operation of the chiller. Lack of proper maintenance will cause dirt to accumulate on the surface of the heat exchanger, affecting the heat exchange efficiency and causing local over cooling. At the same time, if safety control systems such as freezing point protection and pressure protection fail to start in time due to failure or improper calibration, they will not be able to automatically stop the unit before a dangerous situation occurs, which may cause copper pipe freezing and cracking accidents from a single point to a large area.
