Closed loop water circuits of industrial cooling and air conditioning systems loose efficiency and flow as the pipes get old.
Sludge caused by corrosion and bacterial activity blackens the water and causes sediments to develop inside the tubes. The sediments stick to all sections of the cooling circuit, reducing chilled water flow and drastically decreasing the cooling effect and energy efficiency of the system.
FOULING AFFECTS PRODUCTIVITY AND EFFICIENCY
Although unseen, fouling is very common in Evaporator circuit of refrigeration and air conditioning systems. It causes a decrease in the heat transfer coefficient, affecting the compressor’s efficiency and energy consumption. In addition to sediments, the water contains germs and bacteria, such as Legionella, that endanger the system operators and maintenance teams who clean the filters and fix cracks and leaks.
DIFFICULTY OF CLEANING CLOSED LOOP WATER SYSTEMS
Since closed loop water systems are almost completely sealed, they are barely visible and offer extremely limited access. Maintenance personnel cannot identify effectively the reasons for the drop of cooling capacity over time.
CLEANING BY CHEMICAL TREATMENT
Unlike condensers that can be opened and cleaned relatively easily, detailed cleaning of closed systems is practically impossible. The common cleaning method is the stirring of chemicals, but this method is not effective in removing sludge and hardened salts that facilitate bacteria growth and promote corrosion.
In addition, there’s no possibility to asses if the chemical treatment dosage harms specific areas of the circuit, such as the tubes inner walls. The failure to do an adequate cleaning, by means of chemical treatment, causes that the fouling that is not removed provides an even better platform for additional sediment to stick to and become thicker.