Liquid level control system

Abstract

A system for controlling the water level in a boiler, including a liquid level adjuster, conduits connecting the liquid level adjuster to the boiler through housings mounted on the boiler and membranes positioned between the boiler and the conduits to transmit fluid pressure from the boiler to the liquid level adjuster while preventing fluid communication between the boiler and the liquid level control system. Valved bypass ducts extend from the housings to the top of the boiler so that expansion of the water in the liquid level control system due to the firing of the boiler is accommodated by overflow into the top of the boiler rather than by rupture of the membranes. Graduated water columns are provided to permit calibration of the liquid level adjuster, and valves are included in the liquid level control system adjacent to the liquid level adjuster so that the liquid level adjuster may be isolated from the rest of the system and checked for proper operation at any time.

Dependencies are inferred from the claim text.