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Product introduction
1.The configuration of the cleaning solution
Recommended acid lotion: oxalic acid 5%, relievers 1.2%, surfactant 0.8%, acid pickling
temperature 60°C, in this condition the cleaning effect is better.
When use hydrochloric acid to clean the system, in order to avoid corrosion and shorten the
life of the heat exchanger, the concentration of hydrochloric acid should be limited to 3% -5%,
and added at a concentration of 0.2% -0.3% of the release agent. When cleaning, the timely
detection of PH value, when PH = 8, immediately stop cleaning, and then replace it by water.
2. Cleaning method
a) Before connecting the cleaning system must stop unit, turn off the water system circulating
pump, shut down the sluice valve on inlet and return water pipe, shut down the drain valve
and vent valve of the heat exchanger.
b) The flow directions of cleaning solvent and heat exchanger refrigerant are opposite.
c) Pickling: check the system is leak-free, Open the water pump and fill acid solution, turn off
the pump, soaked 2h. open the pump runs continuously and stop 3-4 times. During start the
water pump 0.5h /time. In the pickling process should be timely testing acid concentration,
when the difference value between two adjacent test concentrations below 0.2%, stop
pickling and discharge the waste pickling liquid into the waste tank.
d) Neutralizing: after pickling, mixed NaOH, Na
3
P0
4
, and softened water in certain proportion,
using dynamic circulation method to alkali wash the heat exchanger reach neutralization.
Discharge the neutralized waste discharged into the waste tank.
e) Water washing: After neutralization, with clean softened water repeatedly flush the heat
exchanger 0.5h, and rinse residue inside the heat exchanger thoroughly. Discharge the waste
water into the waste tank.
f) Passivating: the casing heat exchanger is exposed to air for 3-4 h, or use the high-pressure
air purging 2 h. generate passivation layer on surface.
g) After finish the cleaning, close the isolation valve, dismantling cleaning systems and
equipment, and keep it aside.
h) Please contact the waste collection company to disposal the waste liquid.
i) Reconnect the unit water system, and then check if the unit can work normally.
3. Warning about the cleaning
a) The flow direction of the cleaning solution must be the same as requirement.
b) Because the water quality and heat exchangers are used in of different occasions, the
cleaning methods and periodicity may differ, this method is only for reference
c) You can not use nitric acid as a cleaning agent.
d) Cleaning solution and chemical solution is bad for eyes and skin, cleaning process needs
good protection.
e) Please invite professional cleaning personnel to operate.
