A. No. A sudden stoppage of the outflow of steam will cause the water level to fall. The first thing to be looked after is to subdue the heat which is the source from which trouble may arise.
Q. Should the feed water supply be turned on?
A. No. Leave it alone. Should the pump or injector be running, the water level will be recovered gradually as the boiler cools down. If the feed is not on, the sudden admittance of water on the overheated surfaces will cause a disaster. The feed should not be turned on until sufficient time has been allowed to avert such danger.
Q. Are there any appliances by which to guard against accident from low water?
A. Yes. Alarms to call attention by blowing a whistle or ringing a bell when the water is below a certain level. Also fusible or safety plug placed in the heating surface of boiler most liable to be overheated from lack of water.
Q. Of what use is the safety valve?
A. To prevent the accumulation of pressure above a given point.
Q. Should water be left in the boiler when not in use?
A. No. It is better to draw out all the water and properly clean the boiler before leaving.