6. Cycle cleaning to the recommended cleaning time. As the cleaning progresses and the sediment dissolves, the gas generated during the reaction also increases, and the excess air should be discharged through the bleed valve at any time. As the air is discharged, the space inside the heat exchange device increases, and an appropriate amount of the cleaning agent can be replenished.

7. Check the effectiveness of the cleaning agent regularly during the cycle. It can be measured using PH test paper. If the solution is maintained at a pH of 2-3, the cleaning agent is still effective. If the pH of the cleaning agent reaches 3 or more, it is necessary to add an appropriate amount of cleaning agent. The pH of the final solution remained unchanged at 2-3 for 30 minutes without significant changes, ie the cleaning requirements were met.

8. After the cleaning time is reached, the cleaning solution is recovered. Rinse with forward and reverse water with clean water until flushed to neutral and ensure no residue.

9. It is difficult to determine whether there is leakage caused by corrosion under the scale of the heat exchange equipment due to the presence of scale. After the cleaning is completed, it should be pressed again to see if there is corrosion leakage.

10. Ensure that the heat exchange equipment is installed and operated after no leakage.