1.During blowdown, firstly open the main valve for blowdown, then open the first valve, at last the secondary valve( fully open the primary valve and control the secondary valve), the time is 30s.

2.When the first valve is opened, if water hammering sound is heard, stop opening the first valve. Do not open the first valve until the sound is eliminated.

3.After the blowdown is finished, the secondary valve shall be closed firstly then the primary valve, and then the secondary valve shall be opened, and the secondary valve shall be closed.( drain the accumulated water between the primary valve and the secondary valve in order to prevent its corrosion to the valve.)

4.After the blowdown is finished, close the main valve for blowdown, report to the stoker for the finishing of the blowdown and inform the neighbor boiler and make record.