There are two reasons for insufficient heat exchange of evaporator:
Insufficient water flow of evaporator
The main reason for this phenomenon is that the water pump is broken or there is foreign matter in the impeller of the pump, or there is air leakage in the water inlet pipe of the pump (difficult to check and need careful analysis), resulting in insufficient water flow.
Treatment: replace the pump, or take apart the pump to clean the foreign matter in the impeller
Blockage of evaporator (or evaporator tube surface scaling, or crystallization)
The first thing to rule out is the pump.Only when the water pump and the water intake line are normal, we could determine whether the evaporator is blocked or the evaporator pipe scaling.
Evaporator blockage or scaling has a common and very obvious characteristic (only applicable to the medium temperature unit) : There will be no condensation or frost or ice on the compressor surface during normal operation of the equipment.And when you see that you can basically determine that the evaporator is blocked.
Treatment: Disassemble the evaporator, take out the evaporator tube, rinse it with high-pressure water gun or soak it with special liquid medicine.
Attention: Some of the evaporators are cooling chemical liquid. Such as chillers for aluminum oxide ( anodic oxidation) factory. Inside the evaporator is the medicine liquid containing sulfuric acid, when some specific conditions are reached, sulfuric acid will crystallize and block the evaporator. If it is pure sulfuric acid crystal blockage, as long as more than 50 degrees of hot water circulation in the evaporator, the crystallization can be dissolved. Some chiller is used in the electroplating plant, such as acid galvanized.Some acid zinc solution containing potassium chloride. When containing “potassium chloride” liquid through the surface of the evaporator tube,potassium chloride will precipitation crystallization because of the evaporator tube surface temperature is very low (below the saturation temperature).After these crystals accumulate over time, they will wrap the evaporator tube with a thick layer of “potassium chloride”, making the evaporator lose heat transfer ability.We could use ways : mechanical scale removal, rinse with water under heat, treated with 0.5~1% hydrochloric acid, alkali boiling and acid pickling.
HERO-TECH adopt enlarged evaporators and condensers, the unit can operate at temperatures of 45 ℃. We use high quality copper pipe for standard and adopt stainless steel pipeline for corrosive water.
We also have the water tank coil evaporator. The innovate evaporator-in-tank configuration ensure a steady water temperature offered, as the evaporator also cools the tank itself, reduces ambient heat gain, and increases the efficiency.
Post time: Aug-13-2019
