求翻译：锅炉启动后应经常注意水位，锅水受热后，水位将逐渐升高，当超过高水位时，应通过排污阀放水，维持其较低水位。是什么意思？

Should always pay attention to the boiler water level starts, heating pot of water, the water level will gradually increase, when more than high water should drain through the drain valve to maintain the low water level.

Regular attention should start after boiler water is heated, boiling water, the water level will be continued to rise, after more than high-water when the sewage valve when water, should be adopted to maintain its low water levels.

After the boiler starts should pay attention to the water level frequently, after pot water being heated, the water level gradually will elevate, when will surpass the high water mark, will be supposed to turn on the water through the wash water valve, maintains it to compare the low water level.

Startup should generally take the water level of boiler, boiler water when heated, the water level is rising, when when high-water mark is exceeded, through drain valve should discharge to maintain its low water level.

Startup should generally take the water level of boiler, boiler water when heated, the water level is rising, when when high-water mark is exceeded, through drain valve should discharge to maintain its low water level.