# US 11,306,837 B1 · Safety valve for hot water heater > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,306,837 B1 - Document ID: US11306837B1 - Status: Granted - Kind: B1 - Application number: 17/138,389 - Filed: 2020-12-30 - Granted: 2022-04-19 - Earliest claimed: 2020-12-30 - Assignees: JDP W.H.A.T., Ltd. - Applicants: Jdp W.H.A.T. Ltd - Inventors: Joel Thomas Powell; Daniel Steven Nielson - Web page: https://patentgrep.com/patent/US11306837B1 ## CPC - F16K 17/04: spring-loaded - F16K 17/168: combined with manually-controlled valves, e.g. a valve combined with a safety valve - F16K 17/0466: {with a special seating surface} - F16K 17/02: opening on surplus pressure on one side; closing on insufficient pressure on one side (check valves F16K15/00) - F16K 17/082: {with piston} - F16K 17/196: spring-loaded - F16K 17/22: actuated by the difference of pressure between two places in the flow line - F24H 9/2007: {for water heaters} - F16K: VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING {(devices for emptying and evacuating the excess liquid in valves or conduits F16L55/07)} - F24H: FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL (steam generation F22) ## Abstract A pressure actuated water shutoff valve is presented. The shutoff valve comprises an upper housing and a lower housing where the upper housing is coupled to the lower housing. The lower housing has a water inlet and a water outlet with a flow passage therebetween. The lower housing includes a plunger seat configured to receive a shutoff plunger. The upper housing includes an chamber having a piston bore in which reciprocates an piston, coupled to the shutoff plunger. In response to a first pressure condition, the piston lifts the shutoff plunger off its seat allowing water to flow through the lower housing. In response to a second pressure condition, a biasing spring seals the plunger against its seat, shutting off water flow through the valve. ## Claims ### Claim 1 A shutoff valve (10) for use with a container (62), the shutoff valve (10) comprising: a housing (12, 14) having an inlet (34) operatively connected to a source of pressurized fluid (64B) and an outlet (36) operatively connected to the container (62), the outlet (36) having a valve seat (24); a valve member (26) moveable to a first position in which the valve member (26) sealingly engages the valve seat (24) to prevent a flow of fluid through the outlet (36), the valve member (26) further moveable to a second position in which the valve member (26) disengages the valve seat (24) to allow a flow of fluid through the outlet (36); a bias spring (54) urging the valve member (26) to the first position; a piston (18) operatively attached to the valve member (26), the piston (18) being disposed in a chamber (20), the chamber (20) being in fluid communication with the outlet (36) such that the pressure in chamber (20) is equal to the pressure in outlet (36), the piston (18) operating to oppose the bias spring (54) such that pressure in chamber (20) produces a force that urges valve member (26) to the second position, whereby falling pressure in outlet (36) causes the pressure in chamber (20) to fall by an equal amount thereby allowing bias spring (54) to overcome the force urging valve member (26) to the second position, thus allowing valve member (26) to move to the first position, preventing the flow of fluid through the outlet (36) into container (62); and a reset lever (32) operably attached to the valve member (26), the reset lever (32) being movable to an engaged position, in which the reset lever (32) moves the valve member (26) to the second position, the reset lever (32) further movable to a disengaged position in which the reset lever (32) allows the valve member (26) to be moved to the first position. ### Claim 2 (depends on 1) The shutoff valve (10) of claim 1, wherein: the valve member (26) comprises a plunger disposed at a first end of an operating rod (30). ### Claim 3 (depends on 2) The shutoff valve (12) of claim 2, wherein: a second end of the operating rod (30) extends outside of the housing. ### Claim 4 (depends on 3) The shutoff valve (12) of claim 3, wherein: the reset lever (32) comprises a lever member pivotally attached to the second end of the operating rod (30), the lever member having a curved sliding surface (80) that engages the housing (12) to move the valve member (26) to the second position. ### Claim 5 (depends on 4) The shutoff valve (12) of claim 4, wherein: the bias spring (54) directly engages the piston (18). ### Claim 6 (depends on 2) The shutoff valve (12) of claim 2, wherein: the bias spring (54) is retained by a cap (16) having an aperture through which operating rod (30) extends. ### Claim 7 (depends on 6) The shutoff valve (12) of claim 6, wherein: the chamber (20) is in fluid communication with outlet (36) via a sensing port (22) disposed in a proximal end of chamber (20), the bias spring (54) being disposed at a distal end of chamber (20). ### Claim 8 (depends on 7) The shutoff valve (12) of claim 7, wherein: the container (62) is a component of a residential water heater (60).