During operation, in case the serious leakage or blasting happen in the steam drum water level gauge, it is required to disconnect the or steam drum water level gauge , the operating procedures are as follows: 

1. Close the secondary valve of the water and steam side of the steam drum water level gauge.

2. Open the water-discharge valve of the drum water level gauge. 

3. Close the primary valve of water side and steam side of the steam drum water level gauge. 

Flushing of the steam drum double- color  water level gauge: 

1. Open the water-discharge valve of drum water level gauge to flush the  water pipe, steam pipe, water level gauge and water-draining-pipe. 

2. Close the valve of the steam side to flush the water  pipe, water level gauge and water-draining tube. 

3. Open the valve at steam side and shut off the valve at water side to flush the steam pipe, water level gauge and water , steam pipe, water level gauge and water-draining pipe. 

4. Open the valve at water side and slowly close the water-draining valve, if the water level rises quickly, and then it slightly fluctuate, which means it is normal. If the water level rises slowly and does not fluctuate, which means there is jamming  phenomenon, it is required to reflush it until it is qualified.

Precautions for flushing  the drum water level gauge: 

1.  The water level gauge of drum water level gauge shall be slowly flushed( special attention shall be paid to it when it is colder), the operator must stand in the  side of steam drum water level gauge, and should not  stand in front of it. 

2. The water valve of the steam drum water level gauge shall not be opened too wide, otherwise, the security ball shall act to block the waterway. 

3. If the security ball has blocked the access, the valve can be closed then are opened slowly. 

4. The steam drum water level gauge shall be flushed at least three times a week, special person shall be responsible for flushing the water level gauge during operation in every week. When it is found that the indication of steam drum water level gauge is not conformity, the numbers of times shall be increased.

5. After the steam drum water level gauge has been flushed, two steam drum water level gauges shall contrasted. If their indication is not in consistency, they shall be reflushed. Regularly contrast the indication of low-read water level gauge and the steam drum water level gauge at least once every two hours in order to ensure the conformity of indication. Every two weeks the water level alarm shall be tested in order to verify the integrity and sensitivity of the water level alarm.