1.   An industry-commissioned study said a broader requirement could cost billions of dollars extra in line testing and installation of emergency cutoff valves.

2.   A low-water cutoff valve near the boiler automatically shuts off the furnace if the water level drops.

3.   Choose a wand with a cutoff valve to avoid wasting water as you move from one area to another.

4.   If, however, the sight glass reads low and the furnace does not shut off automatically, then a service technician should check out the cutoff valve.