1. Open backwash drain valve and wash drain valve of ultrafilter.
2. Open the inlet valve of ultrafilter, start the backwash water pumps and the oxidizer metering pump. 
3. 30 seconds later, close the washing drain valve .
4. 30 seconds later, open the intake valve .
5. 10 seconds later, open the wash drain valve, close the backwash drain valve.
6. 30 seconds later, open the backwash drain valve and close the wash drain valve.
7. 30 seconds later, close the intake valve and the backwash intake valve, close the backwash pump and the oxidizer metering pump.
8. 10 seconds later, open the wash valve and the wash drain valve.
9. 20 seconds later, close the backwash drain valve.
10. two minutes later, close the wash valve and the wash drain valve.
11. Turn into a standby state.